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Structure to Value Rules Discussed

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Style to Value is a element of Design and style for Excellence (DFX) philosophy together with its other branches this kind of as Style for Manufacturing (DFM), Design for Assembly (DFA), Design for Provide Chain (DFSC) and Design and style for Sustainability (DFS) to title a couple.

As about 70% of the product’s ultimate value is determined through the layout stage, Style and design to Charge methodology is an important strategy for production corporations to obtain a extra specific charge estimation.

What Is Style to Price?

Regular methods have deemed solution price an important element in later growth levels and unbiased from design conclusions. This can consequence in believed product costs that are appreciably bigger than focus on charges. In some circumstances, even redesign may well be wanted which would become an supplemental investment decision.

Style and design to Price tag or Style and design for Expense or DTC is a value management theory that accounts for development, output and assistance fees at the style stage. Style and design to Charge also aims to apply the vital charge technique during the advancement cycle of the venture so that value targets will turn out to be unbiased variables to guide the choice-generating.

Style to Price tag Phases

To implement helpful DTC prior to the production method, a strategic basis should really be adopted.

Defining Concentrate on Price tag

The first stage in applying design and style to charge is to determine the suitable charge of the final product or service. This can be performed by generating various specifications or tiers for the final result. The essential regular or decrease tier would have only the important quality and operation. A tier over this would have some innovation and more characteristics. The major tier would insert even far more features and luxury. The latter can also be regarded as as style and design to worth.

Relying on the undertaking sort, any a single of these tiers can be employed as a beginning point at this phase. This is an critical aspect of DTC as it will assistance to comprehend the wants and scopes of the client and lay out the framework for the subsequent stages.

Value Management and Expense Reduction Tactics

This phase is at the core of Structure to Value methodology. The pursuing area will lay out distinctive charge motorists to bear in head in the solution layout phase that will impact the ultimate product’s selling price.

Layout standardisation

1 of the most critical elements of structure growth in any producing industry is the standardisation of design and style throughout the merchandise selection. This should get into account any resources employed although aiming for modular design as this allows to lower fastened costs tremendously. This approach is certainly not special to Layout to Cost methodology as it is also a single of the essential concentration points for Style for Assembly & Style and design for Production & Assembly.

Use of normal pieces

The use of common pieces is yet another excellent way to even further cut down generation expenses. Collaboration with the suppliers of these parts can also improve flexibility. When standardisation is executed across the overall source chain, it minimizes the established-up and inventory value, thereby simplifying provide chain administration. Consequently this system is also in the emphasis of Style and design for Offer Chain. And finally, there is the included benefit of cutting down expenses affiliated with R&D.

Geographical variables

Producing area is a very important part of price management. There are multiple critical geographical variables to contemplate whilst creating this decision such as supply chains and ecosystems, the availability of components, issues relevant to labor, taxes and responsibilities.

Packaging & transportation

Weight and quantity are the keyword phrases when considering transportation and alongside one another with packaging, these need to be accounted for in the design and style procedure.

Squander minimisation

A person of the most important principles in phrases of squander minimisation is lean producing. The target in this article is on decreasing squander in all output phases. Any attribute on the last product or service that doesn’t include price to the customer is also witnessed as squander and need to be as a result removed from the solution at this stage.

Servicing

Even though not a component of the creation procedure, routine maintenance really should not be forgotten as a expense in just the design. The appropriate style choices can increase maintenance intervals and accessibility for tricky places. Getting a maintenance-welcoming style and design in concentration can therefore cut down long run prices following the generation cycle.

None of these components can be viewed in isolation as they are all intertwined and have immediate prices. Structure to Expense should often be witnessed as a huge-ranging technique that can consist of a multitude of ideas. Relying on the job form and requirements, the style crew really should determine which facets are most ideal when thinking of DTC.

Analysing Effects

This is the most essential phase in DTC as it will decide producing choices. When analysing effects it is essential to appraise if the design at hand matches the goals or if it can be improved. The layout to value system should be recurring until eventually the style fits the targets, surpasses them or are not able to be improved more.

Issues in Layout to Price Implementation

The advancement of design to system can pose various problems. The pursuing sections handle some of the most prevalent ones.

Position tasks

A person of the most commonplace worries all over products price tag is the uncertainty in phrases of responsibility. To conquer this, design and style engineers need to be permitted both of those the liberty and duty alongside with the necessary tools to carry out expense management by way of structure options.

Engineering society

One more tricky factor when putting structure to value into practice is the engineering society as product engineers may well not have an overview of a lot of of the essential value drivers. For addressing this issue, engineers require means to realize prices at the style phase. This need to be achieved without the pointless load of qualified assets.

Ingredient-stage awareness

To carry out all of the aforementioned value management tactics, the style and design engineering team requires to have a ingredient-level knowledge of the made products.

How to Assess Expenditures

The cost variation amongst the aluminium brackets when designed out of 2mm or 3mm sheets

It’s basically really simple to do by utilising the abilities of our  free-to-use producing platform. The combination of manufacturability checks and fast pricing on can make for a terrific software for evaluating fees in the design and style process. You can optimise the part geometry, use of supplies, etcetera. for charge-performance dependent on platform opinions. All of these selections involve a case-by-circumstance analysis and call for the designer to be in the loop with all of the close product prerequisites but the platform can give great Style and design to Price comments.

In the photograph previously mentioned, you can see that each of the brackets are created from the exact aluminium grade sheets but the distinction lies in the thickness. In a good deal of conditions, products are in excess of-dimensioned and built to endure loads and environments to which they will by no means be uncovered. Working with thinner sheet stock can be a good way to lower down on costs but yet again, the design engineer has to be up to day on all of the functional necessities to do so. These very little value discounts truly do include up, specifically when moving on into high-volume manufacturing.

Underneath, we’re evaluating a stainless steel bracket to an aluminium 1. The brackets are exposed to the features in their functioning environment but they never provide a structural purpose in the assembly. The AW 5754 H22 marine grade aluminium presents excellent corrosion defense but so does creating the aspect from AISI 316 2B stainless steel. AISI 316 2B has greater security versus acidic and salty environments than the more popular AISI 304. As you can see, the price per piece is less costly for the components made out of aluminium and since they do not bear wonderful loads and endure intense forces, developing the brackets out of aluminium makes more perception.

comparing aluminium and stainless steel brackets from sheet metal to find the optimal design to cost solution
The rate variance amongst aluminium and stainless steel brackets

In addition to the price info, our platform gives feed-back on the manufacturability of pieces based on your 3D products, so you can fix any challenges to speed up the time to production.

Summary

As a aspect of Design and style for Excellence, Design to Price is a great methodology to provide cost types by using structure conclusions. The vital advantages of implementing this technique occur from expense reduction and cost savings at the starting of the structure. As an added benefit, expense estimations can be attained with reasonably restricted information.

It is vital to bear in thoughts that DTC is not a definitive ruleset but a framework that ought to be altered according to specifications and possibilities and the variability concerning unique projects.

Style and design to Value can pose multiple issues all through implementation, but these can be defeat with smart and efficient administration when earning available all the vital applications and methods for the style staff to have an in-depth knowledge of its ideas.

As DTC is turning out to be more common, we can expect long term investigate accomplished in this region which can deliver makers with additional details to optimise fees and maximize process general performance.

Brazing Explained – Definition, Process, Types

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Brazing is a course of action that joins two or extra metal surfaces by allowing molten metal circulation into the joint. The filler metal has a decreased melting temperature than the sections to be joined to maintain the workpieces from melting.

Despite the fact that brazing is just one of the oldest becoming a member of techniques, it is however applied nowadays for a excellent cause.

What Is Brazing?

Brazing joins metal surfaces with each other with a filler metal which has a small melting place. The process utilizes capillary action wherein the homogenous liquid circulation of the filler content bonds with the foundation metals.

A exceptional good quality in the brazing procedure is that it keeps the mechanical qualities of the metals which are helpful in applications these types of as silver brazing or other very similar metals.

Brazing Course of action

1 of the most critical steps in the metal joining procedure is the cleansing of the base metal surfaces. Emery fabric or wire brush are both good resources to remove contaminants.

Having calculated joint gaps for the liquid filler metal to realize floor rigidity with the workpiece, the brazing operation begins with adequately positioning the assembly. A torch is usually applied to slowly and gradually warmth the workpiece’s metal floor and filler metal into its brazing temperature.

As the filler metal liquefies, capillary motion allows it pass as a result of the tight spaces, thus forming a bond involving the floor of the foundation metals.

The brazed joints are fashioned as it cools down with the assembly.

Materials

These are the metals that are generally joined by brazing:

  1. Aluminium

  2. Cast iron

  3. Magnesium

  4. Copper and copper alloys

  5. Silver

Filler metal requirements

  1. After the molten flux and filler metal solidify, the brazed joint ought to have the envisioned mechanical qualities.

  2. Brazing temperatures should efficiently obtain a good liquid stream from the molten braze alloy into the joints.

  3. Filler metals will have to accomplish appropriate wetting circumstances in order to make powerful bonds.

Variance In between Brazing, Soldering & Welding

Brazing works by using capillary motion to be a part of different metal surfaces. It makes use of a course of action referred to as wetting, whereby the foundation metals are bonded with a melted filler content. The brazing filler metal has a melting issue previously mentioned 450 °C.

Soldering utilizes filler metals that have a melting position beneath 450 °C. While soldering utilizes the same principle as brazing, the principal variance lies in their performing temperatures and hence in the power of the developed joint.

Welding also melts the workpieces in addition to the filler metal. This permits the generation of much better bonds than with brazing. Procedures these as TIG, MIG, and stick welding function at considerably greater temperatures.

Braze welding is a type of MIG/Magazine welding. The big difference lies in the melting point of the filler wires which is noticeably reduced than the father or mother metal. The filler metal is deposited in purchase to fill in the gaps by means of capillary motion. There is no considerable fusion of the parent metals but it might come about in a confined quantity.

Diverse Methods of Brazing

Brazing makes use of various heating solutions to accommodate a wide range of purposes and applications. Warmth can either be used specifically to a joint (localised) or to the full workpiece (diffuse heating).

Localised Heating Tactics

Torch brazing – Combusted gasoline gas is shaped by burning acetylene, propane, or hydrogen with air to warmth and soften the filler metal. Flux is necessary although using this method in order to safeguard the joint, which demands article-cleanup later on on. Torch brazing is generally applied for modest manufacturing assemblies wherever metal body weight is unequal.

Induction brazing – High-frequency alternating existing is provided into a coil to achieve brazing temperature, which heats the workpiece and melts the filler content.

Resistance brazing – Heat is created from the electrical resistance of the brazing alloy, which is fantastic for highly conductive metals. This heating strategy is finest suited for producing straightforward joints involving metals.

Diffuse Heating Techniques

Furnace brazing – Fuel firing or heating things are utilized to convey the furnace to the wished-for temperature. The brazing filler metal is applied to the surfaces to be joined and then the entire assembly is put into the furnace and introduced to brazing temperature. Furnace brazing enables precision in managing the heating and cooling cycles of the metals. The method is frequently performed in a vacuum to guard the braze alloy from atmospheric situations. This also negates the will need for flux defense.

Dip brazing – The workpiece or assembly is immersed in a bathtub of molten filler metal (molten metal bathtub brazing) or molten salt (chemical bathtub dip brazing). Brazing flux is applied to the pieces to stop oxidation. The assembly can be eliminated at the time the molten brazing filler metal has solidified.

Positive aspects

  1. Can join dissimilar metals, compared with most welding approaches.

  2. High generation fees.

  3. Consumes significantly less energy than welding.

  4. Produces cleaner joints compared to most welding procedures.

  5. Foundation metals never soften, preserving their shape and mechanical homes.

Disadvantages

  1. Weaker outcomes in contrast to welded joints.

  2. Simply cannot sign up for factors operated at significant temperatures.

  3. Calls for limited, uniform joint gaps to accomplish capillary motion.

  4. Unclean or contaminated metals could result in leaky joints.

Brazing is utilised in a huge selection of industries because of to its versatility and capability to be a part of dissimilar metals. Fractory’s cautiously chosen producing partners have working experience and know-how in this industry as brazing is aspect of the welding products and services we give.

Stafford producer celebrates as new state of the art facility unveiled bringing new jobs and increased generation to the region

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Alpha Manufacturing has formally unveiled its new condition-of-the-artwork production facility at Beacon Park, Stafford.

The completion of the 35,000sq ft Alpha Manufacturing Chemical Systems site, on Wednesday 7th September, significantly improves the precision engineering abilities for leading sheet metal producer Alpha Manufacturing.

Developing 50 new positions for the spot, the new facility, portion of The HEX Team, accommodates higher-precision engineering and producing processes supporting the manufacture of factors for INEOS Electrochemical Options.

Running 24/7 shift-patterns, the crew primarily based at Beacon Park will be part of above 500 other customers of The HEX Group crew based at Hixon.  Associates from each Alpha Producing and INEOS Electrochemical Solutions marked the unveiling which will provide a increase to employment and production in the place.

Paul Clews, Running Director at Alpha Producing, stated the new web-site was element of the group’s ongoing investment in developing environment course production listed here in Stafford.

He explained: “Our new point out-of-the-artwork facility is the end result of months of challenging get the job done and testament to our continued commitment to investing in the neighborhood place.

“The web site will continue on to produce and devote in the engineers of the long term making new chances and growing Alpha Manufacturing’s entire world-class engineering facilities in the region.

“Alpha Production Chemical Technologies is portion of our commitment to collaborations which generate innovative alternatives for products of the foreseeable future and is a welcome addition to the HEX family.”

Commenting on the opening, Terry Healy, Company Device Manager, INEOS Electrochemical Alternatives suggests: “It is a momentous day for Alpha Manufacturing Chemical Systems. We are delighted to be bringing new techniques and experience to Stafford many thanks to the world-course engineering standards of Alpha Manufacturing.  Our collaboration is helping to help the upcoming progress of the industry and we are pleased to mark this new partnership here in Stafford.”

Alpha Production is a family-owned business proven in 1989 which specialises in fabricating sheet metal in the Eire.

The company now employs more than 150 people from designers and engineers to creation staff, welders, and equipment operators to deliver integrated remedies for firms across the world.

Non-Destructive Testing (NDT) | Process, Types & Applications

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Testing serves an important function in virtually all manufacturing processes. It ensures that the final product’s quality matches the design specifications and is fit for the service environments it will operate in.

There are many ways to classify testing techniques. One of the most popular classifications is destructive and non-destructive testing.

In this article, we shall take a deep dive into what non-destructive testing (NDT) is, some of its popular types and its applications in some common industries.

What Is Non-Destructive Testing?

Non-destructive testing refers to the use of testing techniques that do not alter any of the properties of the tested product. These properties could be its strength, integrity, appearance, corrosion resistance, conductivity, wear resistance, toughness and so on.

Non-destructive testing is also known as non-destructive evaluation, non-destructive analysis, non-destructive examination and non-destructive inspection.

When the product passes an NDT test, it can still be used. There’s no detrimental effect on the specimen because of the test.

This advantage makes non-destructive testing a very useful method for products that are freshly manufactured as well as for those that are already in service.

When the scope of work is simple, using a single NDT process may be sufficient. But in a lot of cases, a combination of techniques and test methods are used for concrete information about the product characteristics.

Difference Between Non-Destructive and Destructive Testing

Non-destructive and destructive testing have some similarities in their objectives but there are significant variations in the core use cases and application methods. In this section, we shall compare and contrast them based on some important factors:

  • Purpose

  • Cost efficiency

  • Time

  • Wastage

  • Safety

  • Reliability of results

Purpose

The purpose of each type of testing is to ensure that we have a safe product. With destructive testing, however, the intention is to find the operational limits for a product through tests such as fatigue and tensile tests.

On the other hand, with NDT, we check whether a manufactured product or one that is already in service is good enough to function satisfactorily in its service environment. We may also use it to assess the extent of wear and tear such as the use of ultrasonic thickness measurement for steel plating of ships.

Cost efficiency

There are two ways in which non-destructive testing is more cost-efficient compared to destructive testing.

Firstly, it does not damage the test specimen. After evaluation through NDT, it will remain just as effective as before and can be put into service right away.

Secondly, NDT can identify potential issues in machinery that is in service, such as a pressure vessel, and recommend replacement before failure occurs, thereby saving breakdown costs that are far costlier than temporary planned downtime for a single part replacement.

Time

When it comes to time, NDT is more effective again. Destructive methods by nature are far more time-consuming processes. This is mainly because destructive testing processes are mostly manual and we can automate fewer components of it. They also require longer preparation and inspection times.

NDT, on the other hand, does not even always need the removal of parts from service thereby saving valuable time. For destructive testing, work must be halted and machines stopped for testing which increases downtime.

Wastage

A test product that undergoes destructive testing becomes unsalvageable. At times, entire machines have to be discarded. 

Some examples of destructive methods that create wastage are tensile tests, 3-point bend tests, impact tests and drop tests.

This is not the case with non-destructive testing. In some cases, the destruction may be necessary but in a lot of other cases, non-destructive methods will give us similar or better results.

Safety

Destructive testing is carried out before a product is put into service to determine its operational limits. This may be necessary for some products such as PPE where they must be made to certain standards but destructive testing cannot be used for products in service.

In such cases, NDT methods can help us identify worn-out products and parts so we can replace them. By ensuring that critical equipment is well within desired limits, the number of safety incidents can be brought to a minimum.

Reliability of results

Both destructive and non-destructive testing can give very reliable results. Destructive testing can only test a small number of samples (lot sampling). Non-destructive testing, on the other hand, can test entire batches. 

NDT is also a better alternative to find discontinuities and defects in a part.

Non-Destructive Testing Methods

Visual testing




Visual Testing

Visual testing remains the most popular NDT method across all industries. It involves taking a thorough look at the specimen and finding defects that are visible to the naked eye.

It is a quick and feasible method of tracking product quality at every stage of the manufacturing process as well as for those products that are in service.

With visual inspections, we can detect corrosion, cracks, welding defects, deformation, etc. All we need are simple instruments such as rulers, gauges or a camera.

When inspectors are not able to reach hard-to-access places or dangerous environments, drones can often be the solution.

Many industries are in fact using AI and machine learning to improve visual inspection results. For instance, such technology is becoming common in the maintenance of conveyor belts, rollers and pulleys in conveyor systems.

Advantages of visual testing:

Disadvantages of visual testing

  • Only works with surface defects

  • Possible misinterpretation of flaws

  • Cannot detect minute defects without additional optical instruments

Ultrasonic testing



Ultrasonic Testing


Ultrasonic Testing

Ultrasonic testing remains the most popular nondestructive testing method after visual testing. 

In this method, a high-frequency sound wave generated by a transmitter travels through the object under test. The frequency of this wave is usually between 1 and 10 MHz.

The wave distorts when encountering a change in the density of the material. This change in the transmitted wave is captured by a receiver.

The equipment then measures and analyses the received wave to understand the nature and depth of the defect. The equipment can also calculate the thickness of the specimen by dividing the wave speed in the material by the time taken for travel.

There are many types of ultrasonic testing available each with its own nuances and field of application. These are pulse echo testing, immersion testing, guided wave testing and phased array ultrasonic testing to name a few

We can identify defects such as cracks, abrasions, thinning, pitting and corrosion using ultrasonic inspection.

Advantages of ultrasonic testing:

  • Quick

  • Clean

  • Reliable

  • Portable

  • Safe and easy to use

  • Highly accurate and sensitive

  • Ability to gauge dense materials

  • Detection of surface and subsurface defects

  • Identifications of minor defects not visible to the naked eye

Disadvantages of ultrasonic testing:

  • Requires training

  • Needs a smooth surface

  • Difficult to use with thin materials

  • Part geometry may create complications

  • Wave propagation speed in tested material must be known for accurate results

  • Couplants are required for smooth wave transfer from the transmitter to the specimen

Liquid penetrant testing



Liquid Penetrant Testing


Liquid Penetrant Testing

Liquid penetrant testing is another popular non-destructive testing method used to identify surface-level defects.

In this method, a low viscosity liquid (penetrant) enters the surface defects such as cracks, fissures and voids. The excess liquid is then wiped off and the specimen is left alone for some time (penetrant dwell time).

The inspector then applies a developer that allows the penetrant to move towards the surface. The specimen is again left alone for a prescribed amount of time (developer dwell time).

Now, the inspector performs the surface inspection. If the dye is visible, it can be inspected with the naked eye. In the case of fluorescent dyes, black light is needed for inspection.

We can detect surface discontinuities such as cracks, porosity, seams, laps and leaks using this method.

Advantages of liquid penetrant tests:

  • Works with many materials. Material properties such as magnetism, conductivity and metallic/non-metallic do not matter

  • Can spot tiny defects such as hairline cracks

  • Suitable for complex part geometries

  • Low cost

  • Can test large areas

  • Portable

  • Easy to use

Disadvantages of liquid penetrant tests:

  • The depth of defects is not known

  • Risk of exposure to toxic fumes

  • Cannot identify subsurface defects

  • Does not work with porous materials

  • Time-consuming, generally needs more than 30 minutes

  • Messy operation, pre- and post-cleaning are necessary

  • Involves handling of chemicals and therefore not it’s not as safe as other methods. Chemical disposal may also become an issue

Radiographic testing



Radiographic Testing


Radiographic Testing

Radiographic testing uses radiation to spot internal defects in parts. X-rays work well with thinner materials whereas gamma rays are better for thicker materials.

The specimen is placed between the radiation source and a recording media. When the radiation falls on the part, the amount of radiation that exits the part in different locations is captured. A physical radiography film or a digital detector is used as the recording media.

The test allows us to obtain the shape and size of internal defects by changing the angle of radiation exposure.

We can use radiographic testing to pinpoint defects such as cracks, thinning, corrosion, voids, insufficient fusion, porosity, excess root penetration and laps.

Advantages of radiographic testing:

  • Can test complex structures

  • Documentation is permanent

  • Works with a range of materials

  • Needs minimum surface preparation 

  • Can record surface and subsurface defects

  • Portability is possible for gamma ray testing

  • Less misinterpretation of results compared to other methods

Disadvantages of radiographic testing:

  • More expensive

  • Needs two-sided access to specimen

  • Not as effective for planar and surface defects

  • High voltage and radiation can be harmful to personnel

  • Skilled personnel needed for execution and accurate interpretation of results

Magnetic particle testing



Magnetic Particle Inspection


Magnetic Particle Inspection

Magnetic particle testing is also a fairly popular NDT technique because of its fast execution where no surface preparation is needed.

In magnetic particle testing, the part is placed between permanent magnets or electromagnets. The strength of the field is an important factor since a stronger field gives better results.

When the part under inspection is placed into the field, a magnetic current starts flowing through the specimen. If there’s no defect, an uninterrupted magnetic flux field is obtained.

But if it comes across a defect, the magnetic field bends and a part of it leaks out. This leakage is also known as the flux leakage field.

In order to identify the defects via these leakage points, magnetic particles are used. These particles are applied to the test specimen and they are pulled into these leakage points because of the uneven magnetic flux density.

We may either use magnetic particles that can’t be seen with the naked eye or fluorescent ones for better visibility. 

The width of the magnetic particle strips is wider than the defect’s width. As a result, it can reveal minute defects with an opening width of up to 0.001 mm and depth of 0.01 mm.

With this technique, we can detect defects such as cracks, pores, laps, inclusions, seams, laminations, shrinks, flakes, welding defects, machining tears and also service-related or fatigue cracks.

Advantages of magnetic particle testing:

  • Easy to use

  • Portable setup

  • High sensitivity

  • Immediate results

  • Usually inexpensive

  • Can work through thin surface coatings

  • Parts with complex geometries are also suitable

  • Visual indication of the shape and size of the defect

  • Can detect surface defects well. Also works for subsurface defects to an extent

Disadvantages of magnetic particle testing:

  • Can only test small areas at a time

  • Does not work with non-magnetic materials

  • Testing may burn the particle if the field is too strong

  • Coatings thicker than 0.1 mm need removal for testing

  • Demagnetisation of test specimens is necessary but may be tricky

  • Can only work for subsurface defects that have a depth of up to 3 mm

Eddy current



Eddy Current Testing


Eddy Current Testing

Like magnetic particle testing, eddy current testing is another electromagnetic testing technique. It works on the principle of electromagnetic induction.

When current passes through any current-carrying conductor (primary conductor), it generates a magnetic field (primary field). 

When we place a second conductor (test specimen) in this magnetic field, the primary magnetic field induces an opposing electric current in this conductor.

This current is known as eddy current and it is proportional to the change in the magnetic field as the alternating current in the primary coil rises and falls during every cycle.

The fluctuating eddy current creates its own magnetic field (secondary field) that opposes the primary field and affects the voltage and current flowing through the primary conductor.

As the test specimen’s magnetic permeability and electrical conductivity changes because of the defects, the magnitude of the eddy current changes. These changes can be recorded by using the primary or the secondary coil and analysing them to get more information about the defect.

There are also other testing methods similar to eddy current available. Remote field testing, for example, finds use in detecting defects in steel pipes and tubes. The main difference between the methods lies in the coil-to-coil spacing.

With eddy current testing, we can detect flaws such as cracks, corrosion, laps, lack of fusion, magnetic inclusions, porosity and wear.

Advantages of eddy current testing:

  • Quick

  • Portable

  • Immediate results

  • Minimal part preparation

  • Can be a non-contact process

  • Works with complex part geometries

  • Capable of automation for uniform parts

  • Can spot surface and subsurface defects up to 0.5 mm in size

  • Multipurpose. It can also measure coating and material thickness, identify materials and their heat treatment conditions

Disadvantages of eddy current testing:

  • The penetration depth depends on many factors

  • Cannot detect flaws parallel to the part surface

  • Only works with electrically conductive materials

  • Requires high-skill personnel for accurate interpretation of results

These are some of the most popular NDT techniques used across the industry today. Apart from them, there are many other NDT methods for very specific applications. Some of these are acoustic emission testing, thermal/infrared testing, vibration analysis, leak testing (e.g. mass spectrometer testing), rebound hammer testing, laser testing and so on. 

NDT Applications

NDT has a wide range of practical applications. But we can divide all of them into one of the following two categories: quality control and condition monitoring.

We can use nondestructive testing to carry out a quality assessment of the manufactured parts to determine that they meet the desired specifications. We may also use it to assess the condition of parts that are already in service and whether they are safe for further use.

Some common industrial applications of NDT are as follows:

Structural mechanics

NDT can verify the structural mechanics of a wide range of products and structures. It requires minimum intervention and is capable of carrying out routine as well as special inspections without aggravating the issues present in the structure. We may also use it to inspect parts that are not as accessible.

When it comes to civil engineering applications, nondestructive testing can inspect structural foundations, cultural heritage monuments, bridges, buildings, etc.

In mechanical engineering, we use NDT for the inspection of loaded machinery such as shafts, turbomachinery, batteries, etc.

Techniques used in this field include ultrasonic testing, radiography testing, visual testing, acoustic emission testing, terrestrial laser scanning, photogrammetry, tacheometry, infrared thermography, etc.

Welding

NDT techniques can identify the various defects that occur during the welding process. We have enumerated many welding defects in the previous sections that we can reliably test through NDT.

As a quick recap, we can use NDT inspections to identify both external and internal welding defects.

External defects include cracks, porosity, undercut, underfill, spatters, overlaps, arc strike and excessive penetration. Internal defects include internal cracks, slag inclusion, tungsten inclusion, internal porosity, internal blowholes, lack of penetration and lack of fusion.

Medical

NDT methods have been revolutionising the medical industry for several years now. They help to accurately diagnose and treatment at the skin as well as the internal level.

Some notable NDT technologies that have become common terms in the medical industry are ultrasound imaging, radiography testing, and echocardiography.

Manufacturers also use NDT methods to test medical implants for fine defects. Such testing prevents subsequent failures when the components are already in use.

Summing it up

Nondestructive testing is quickly becoming the go-to test method for spotting defects in almost every discipline. Today, NDT finds application in sectors such as aerospace, military, medical, nuclear, marine, power generation, manufacturing, etc.

The increasing popularity has prompted further research and the existing processes are becoming better and more capable with every passing year.

Soldering Explained – Definition, Process, Types

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Soldering is a process that joins two or more types of metals through melting solder. The first soldering iron was developed in 1896 by Richard Schneider and August Tinnerhol and was called the “First Electric Heating Apparatus”.

Soldering is commonly used in electronics, as it is simple and safe in joining sensitive materials. Likewise, the process is also known for metalworking, plumbing, roofing and joining wires. Let’s take an in-depth look into soldering to find out more.

What Is Soldering?

Soldering uses a filler metal with a low melting point, also known as solder, to join metal surfaces. The solder is usually made up of an alloy consisting of tin and lead whose melting point is around 235°C and 350°C, respectively.

But when tin and lead are mixed then the melting point of the mixture is reduced to 183°C. The alloy is melted by using a hot iron at above 316 °C (600 °F).

As the solder cools, it creates a strong electrical and mechanical bond between the metal surfaces. The bond allows the metal parts to achieve electrical contact while it is held in place.

Note that lead-free solders are increasingly used as an alternative to environmentally harmful lead-based solders due to regulations.

Soldering Process




Hand soldering

The first step in soldering is to wear protective gear in a well-ventilated area. Next, the soldering iron should be preheated. For cleaning the soldering tip, you can use a wet sponge. Likewise, any residue on the workpiece surface should be wiped off.

After finishing the preparations, it’s time to heat the base metal to a working temperature using the hot iron. Doing so will help prevent thermal shock, activate the solder, and overall improve the quality of the joint. A good indicator that the metals are well-heated is when the molten solder freely flows into the joint. The filler material solidifies as it cools down, making it the best time for inspection.

The key to successful soldering is ensuring that the metals being joined are clean and free of any oxides or other contaminants.

Desoldering

From time to time, components fail and need replacement. When these components are mechanically held in place with solder, a process called desoldering removes the material cleanly and safely.

A soldering iron or a heat gun can be utilised to melt the solder, allowing you to safely remove any soldered components. To remove the liquid solder, you can use a desoldering pump as a vacuum, or a soldering wick to absorb the molten solder.

Alternatively, you can resort to an aggressive method using compressed air that can blow off the liquid solder.

Soldering vs Welding

While soldering and welding are processes that join two pieces of metal alloy together, there are some key differences in how the metals are joined.

Soldering uses melted filler metals to bond heated base materials. It works at a lower temperature than welding but requires preheating the base materials to create an effective joint.

Welding runs at higher temperatures to melt both filler material and workpiece together. It results in a stronger bond, with some changes to the mechanical properties of the metal from heating and cooling.

Metals

Soldering works well with the following base metals:

  • Gold

  • Silver

  • Iron

  • Brass

  • Copper

  • Aluminium

  • Steel

  • Titanium

While some of these metals can easily be soft-soldered, harder metals may require filler materials with a higher melting point to be joined.

Soldering Tools

Soldering irons are hand tools that heat the solder above its melting temperatures. They offer a wide variety of sizes, which is great for different applications. The tip of the iron has different types and sizes that suit a variety of projects.

Soldering guns are employed when higher temperatures require more power. A soldering gun heats quicker and offers better flexibility as it can be operated in confined spaces, heavy electrical connections, and metalworks.

Soldering stations are multipurpose devices that have everything covered for minor projects. They are more durable than regular soldering irons due to them being equipped with sensors, fuses, alerts and temperature regulation.

Solders

Lead-based solder

Most soldering projects are typically performed using lead solder consisting of a 60-40 tin-to-lead ratio. This solder melts in a range of 180 to 190°C and is usually the best choice for soldering electrical connections.

Lead-free solder

As a way to mitigate the use of harmful elements, lead-free solders were developed. These usually come as solder wire and are composed of metals with higher melting points: tin, copper, bismuth, silver, brass, indium, and antimony.

Flux core solder

These filler metals come as paste or soldering wires that contain a flux solder core. The flux releases a protective layer around the workpiece as it is consumed, which achieves cleaner electronic connections and better wetting properties.

Flux

Rosin flux (alternatively called passive flux) is used for electronics as it leaves a residue that doesn’t lead to corrosion.

Acid flux solders contain aggressive properties, which are effective in removing the oxides of the metal surface. This leads to stronger and cleaner metal joints compared to rosin.

The type of flux can be broken down into two groups depending on its application. No-clean flux is made with natural rosin or other synthetic materials, requiring no post-cleanup, while water-soluble flux contains water-soluble resin that is easily removed by rinsing.

Heating Methods

pipework on a factory workbench, blow lamp soldering

While the concept of soldering is fairly simple, there are different heating methods that depend on the application or project. Primitive methods involve a fire heating element through butane, but this has now evolved into more advanced techniques.

Laser

Commonly used in delicate electronics, lasers at 30-50 watts can accurately create a soldered joint while preventing heat in the surrounding area. It is commonly used on circuit boards where the components are compact.

Induction

Copper coils induce heat to the solder by using an oscillating high-frequency alternating current. Induction allows for an even application of thermal energy to heat solder, being a great application to cylinders and pipes, minimizing holes and maintaining uniformity.

Resistance

This soldering form generates heat by applying an electrical current to the solder and soldering iron. Heat is generated in a small space and it dissipates quickly, reducing the risk of damaging components.

Infrared

This method uses infrared (IR) light as a mode of heat transfer to the targeted area. It only takes a few seconds, reducing the heat exposure time of the surrounding area.

Types of Soldering

Here are three soldering types that are used at varying temperature levels that result in different joint strengths:

  • Soft soldering (90 °C – 450 °C)

    The solder melts alloys containing lead that has a low melting point. With a lower melting point, this soldering type minimises the thermal stress wherein the base metals are subjected.

  • Hard soldering (above 450 °C)

    Brass and silver are usually hard soldered, with the use of a flame via blowtorch to melt the filler metal. Hard soldering has better mechanical strength than soft soldering, which applies to crafting jewellery and some machining operations.

  • Brazing (above 450 °C)

    This soldering type uses metals with a much higher melting point compared to hard and soft soldering. It produces the strongest result, which is perfect for metal repairs and for pipe joining.

Advantages of Soldering

  1. Soldering is operated at lower temperatures compared to common welding methods.

  2. Most metals and non-metals can be soldered.

  3. A simple process makes it easy to learn.

  4. The base metal isn’t melted in the process, unlike welding techniques such as stick welding, flux-cored welding, etc.

  5. Soft soldering can be undone using a desoldering tool without damaging the base materials.

Disadvantages of Soldering

  1. Weaker joints compared to other welding methods such as MIG and TIG.

  2. Soldering isn’t suitable at high temperatures, as the solder has a low melting point.

  3. Heavy metals aren’t suitable for soldering.

  4. Melted solder might leave a toxic flux residue.

  5. Improper heating may cause deformities or voids in the solder.

Applications

automated soldering in circuit board manufacturing

Electronics Industry

The most popular application of this fusion process is electronics soldering, where wires are joined and electronic components are fused to a circuit board. This technique allows soldering components together with the luxury of desoldering when needed.

Roofings

Soldering can be used in creating leak-proof roofings wherein the galvanised steel is infused with solder. The soldering iron tip is far broader when used in this application compared to other uses.

Sections

Soldering is applied in the piping and plumbing industry as a way to create joint sections. It is a straightforward process and a reliable solution in sealing the connections in copper pipes, for example.

Art

Soldering can be used to create stained glass art, wire modelling, sculptures, jewellery and other creative works.

Metalwork

The soldering material can be used to fill cavities and even out rough surfaces. This process is practiced to fuse metal sheets, pipes and other applications where metals don’t undergo high temperatures.

Automation

Technology allows us to automate the soldering process through the use of programmed robots. Not only does it create precise joints but it is also fast in production speed.

Important Points to Remember

Soldering plays a vital role in the electronic industry along with several applications. When done correctly, it can provide strong and reliable mechanical joints.

While the fundamental concept of soldering is simple, innovations are reshaping how this process is done, offering more versatility and usability. Today’s technology allows automation, similar to welding processes like MIG and spot welding, with different solders depending on the application.

As we continue to traverse into micro and nanotechnology, it’s very likely that soldering or another similar form will develop to join these small electronic parts.

The HEX Group | Conversing Psychological Health

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At any specified time, 1 in 6 working-age adults have symptoms related with inadequate mental health and fitness. From depression to anxiousness, absence of self-assurance or pressure, mental health and fitness can have a massive effects on how men and women understand the entire world all-around them and make each working day performing tasks much more tough.

As portion of Suicide Avoidance Month, we talk to Karen Barnacle, Group HR Supervisor at The HEX Group, about recognising and supporting colleagues going through psychological overall health.

“One in four of us experience mental health sickness at some place in our lives. It can affect us all in distinctive techniques. Alterations in mood and behaviour are normally indicators an particular person is having difficulties but for some the signs will be significantly less clear. Recognising an unique who is having difficulties might be tough, which is why one of the most important items I can do as Group HR Manager is to make sure that strains of communication are constantly open up and colleagues know the place to switch if they require support.

Make time to communicate

“Being informed of modifications in people’s mental wellness and having the time to look at in and question concerns is just one of the most significant ways in supporting to aid anyone who might be having difficulties. This is why, at The HEX Team, we offer a totally free telephone counselling support to all workers.  It can be difficult to open up up to the folks closest to you, which is why we’ve partnered with Wellbeing Solutions, supplying our colleagues obtain to this priceless, private services.

Be mindful of your approach

“As colleagues we are not trained therapists, but we are very passionate about supporting our crew, which is why we keep frequent one to types with staff and have absolutely free help tools available for these who truly feel they are struggling with lower temper or mental health and fitness worries.

“Staff wellbeing will usually be a top rated priority and we are frequently incorporating new initiatives to support our employees together with the introduction of far more Psychological Health and fitness To start with Aiders later on in the yr.

What can you do to assistance?

Often, when men and women are struggling the most valuable point is to have someone who will hear, or to hear a caring voice. It is then significant to signpost people to the ideal place for professional help. Organisations this kind of as Thoughts or Samaritans are great means.  At The Hex Group, our door is usually open and if you’re anxious about a colleague, be sure to share your considerations with us possibly in particular person or via our Shout Up scheme.

Smaller acts of kindness

Giving to support another person you can see is battling may well be the connection they necessary. Building someone a cup of tea, asking if they want to sign up for you for lunch are basic things that could make the big difference to somebody’s day.

Flux-Cored Arc Welding (FCAW) Explained

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Flux-cored arc welding (FCAW) is an automatic or semi-automatic process that uses a consumable tubular electrode in the electric arc to join metals. It was introduced as a solution to overcome the limitations of shielded metal arc welding (SMAW) aka stick welding.

FCAW welding has become an ideal choice for welding ferrous metals. This welding technique is used in shipbuilding, construction, and mechanical industries. Its popularity comes from efficiency and portability compared to other welding processes.

Let’s take a deeper look into this welding technique.

What Is Flux-Cored Arc Welding?

Flux-cored welding is an arc welding process that deposits filler material with a shielding flux in the weld puddle. Fusion takes place when a welding arc is established between the flux-cored electrode and the base metals.

The tubular electrode wire is supplied through a spool and guided by a welding gun to the weld joint. As the electrode melts, the flux inside it releases a shielding gas to protect the weld pool from atmospheric contamination.

Flux-cored welding is often confused with gas metal arc welding (GMAW) as both welding techniques can be performed on the same or similar welding equipment but they do have subtle differences between them.

Differences Between FCAW and GMAW (MIG/MAG)

Generally, flux cored and gas metal arc welding both use the principle of using a shielding layer and a continuous wire-fed electrode.

FCAW welding uses a flux-cored electrode that emits a protective shielding layer as it is deposited into the weld pool. FCAW emits toxic fumes from the flux which blocks the weld area from contaminants. This process is favoured for ferrous metals as it requires little-to-no pre-cleaning.

In some cases, FCAW can use shielding gas on top of the primary shielding flux to further protect the weld pool from oxidation. Dual-shielded FCAW offers more consistent mechanical properties and higher deposition rates than solid wire or stick electrodes.

GMAW (MIG/MAG welding) uses a solid wire electrode along with external shielding gas to prevent contamination of the weld metal. GMAW leaves more weld spatter than FCAW and offers less penetration. MAG and MIG welding offer versatility to weld a wide variety of metals.

GMAW has a bigger electrode wire (2 – 5 mm) compared to FCAW (0.9 – 3.2 mm).

Although these are two separate welding types, the only major difference lies in shielding the weld zone using electrodes and shielding gases.




What is Flux Cored Arc Welding? (FCAW)

Flux Cored Welding Process

The FCAW process utilises the heat from the arc generated between the tubular electrode and the workpiece. The electrode is hollow, with a flux core inside acting as a shielding agent while it is deposited in the weld zone. As the flux core is consumed, it produces a barrier protecting the weld from atmospheric contamination.

There are two main options for performing FCAW:

  • FCAW-S (Self-shielded) – Self-shielded welding solely relies on gaseous protection from the flux core and its slag deposits. This process is mostly used for outdoor projects that have unpredictable conditions.

  • FCAW-G (Gas/Dual-shielded) – Dual shield welding uses flux-cored wires along with external shielding gas to provide additional protection for the weld area. This process allows higher deposition rates and offers better penetration against thicker metals.

Certain conditions can also influence the choice for the welding process, such as portability, desired mechanical properties and base metal.

FCAW can be performed semi-automatically wherein a welding professional controls the welding torch, individually adjusting the parameters. It can also be performed fully automatically by implementing robots that can create consistent travel joints.

Flux Cored Arc Welding Variables

To achieve optimum results, the following parameters can be adjusted for every operation:

  • Wire feed speed

  • Contact tip distance

  • Travel speed

  • Polarity

  • Travel and work angle

Electrodes/Wires

There are three main flux-electrode classifications for this welding method:

  • Gas-shielded all position – All position flux cored welding wires are generally smaller than 1/16 inches (~1.6mm) with a fast-freezing flux core. These electrodes are mainly applied to offer more control when welding overhead. As a drawback, these can’t be used with a base metal that has high levels of contamination.

  • Gas-shielded flat position – Flat position welding electrodes are usually greater than 1/16 inches (~1.6mm) and offer fast deposition rates, suited for thicker metals. These are mainly employed for horizontal or flat welding positions and it fares better than all position electrodes against base metal contamination.

  • Self-shielded –  These electrodes come in handy for outdoor applications, such as construction or fabrications. They are also perfect for welding galvanised steel or for rare occasions wherein gas cylinders are hard to reach.

Selection of the type of electrode will primarily depend on the following criteria: type of welding current, position, desired mechanical properties, chemical composition and environment.

Materials

While flux-cored arc welding is known for welding ferrous metals, it’s also popular for its versatility when welding the following metals:

Shielding Gas

Dual shield welding shielding gas comes from cylinders or tanks to the welding torch through a supply hose. These shielding gases protect the weld pool from the atmosphere, reducing the risk of porosity and brittleness. Both inert and active gases may be used as gas shielding elements.

  • Carbon dioxide – FCAW welders prefer using carbon dioxide because of its low cost and deep penetration. Since CO2 is an oxidising gas, deoxidising elements are added to the flux-cored wire to remove the oxygen.

  • Argon and carbon dioxide – A combination of the two gases is sometimes used to generate less spatter. It is usually in the ratio of 75% argon and 25% CO2, with a filler metal resulting in higher strength properties than pure CO2 gas.

  • Argon and oxygen – Pure argon is sometimes mixed with 1-2% oxygen to weld metals that can be corroded with CO2, such as stainless steel. The mixture also promotes less spatter to the weld area, similar to the mixture of argon and CO2.

Welding Gun

  • Air-cooled – Normally, air-cooled guns are sufficient for projects with welding currents less than 500 amperes. The surrounding air is enough to cool down these flux-core guns. Having a shielding gas present further cools down the welding gun. Additionally, air-cooled guns are cheaper and lighter, which makes it easier to manoeuvre and create quality weld beads.

  • Water-cooled – It is recommended to have water-cooled guns for operations requiring a welding current greater than 600 amperes. Typically, it is the preferred choice for continuous flux-cored arc welding operation, where the gun is exposed to high temperatures for longer periods. Water-cooled guns allow water to flow around the nozzle and contact tube to quickly reduce temperatures.

Wire Feeder

Flux-cored arc welding machine, wire feeder and welding gun

The continuously fed tubular electrode is driven by a wire feed motor. The wire feed speed can be configured in this machine to control the delivery from the spool to the welding torch.

Power Source

It is desirable to have a direct current (DC) as the power source for this welding method since it is mostly applied to ferrous materials. DC power supply also creates a more stable arc and offers better penetration.

  • DC positive polarity (DCEP) is the most common power setting since it offers a deep penetration to the weld metal. It is also preferred when using external shielding gas to safely deposit the filler metal to the weld joint.

  • DC negative polarity (DCEN) is utilised for welding thinner metals. While self-shielding flux electrodes can be used with both positive and negative polarities, DCEN is sometimes the choice to achieve a certain result.

Applications of Flux Cored Arc Welding

General Repairs

Some prefer using flux-cored welding in performing general repairs for its portability. It can endure harsh outdoor conditions, at the same time it has the ability to weld ferrous metals.

Pipelines

Due to FCAW welding producing welds with minimal porosity, the pipeline manufacturing industry prefers operating with this technique. With welds created with consistent mechanical properties, pipes have unparalleled strength and durability.

Manufacturing

The manufacturing industry takes advantage of automating the process of flux core arc welding through the use of robots. This results in a precise and consistent welding seam, while all the welding parameters are controlled.

Shipbuilding

The continuously fed tubular electrode allows for an efficient operation in shipbuilding. With the number of minor components to weld together, shipbuilders have to constantly change welding positions. Flux-cored welding works best, as it is easy to perform while shipbuilders manoeuvre the welding torch at varying angles.

Underwater Welding

Divers take advantage of the protection offered by the protective gas layer produced by the flux-cored electrodes. Performing this wet welding procedure requires skill and training as the hazards are beyond comparison to the conditions above ground.

Advantages of Flux Cored Arc Welding

  1. FCAW offers higher penetration than MIG/MAG welding.

  2. Ability to weld ferrous metals since the electrode deoxidises the base metal.

  3. More portable than MIG welding since we can use FCAW without a shielding gas tank.

  4. Easier to learn than stick and TIG welding.

  5. FCAW and MIG welding use the same machine.

  6. The flux creates a shielding layer, allowing it to work well with outdoor welding.

Disadvantages of Flux Cored Arc Welding

  1. Slag cleanup.

  2. Semi-automatic FCAW results in poorer weld beads than TIG welds.

  3. Flux tubular electrodes are more expensive than solid wires.

  4. Flux disintegration results in excessive toxic fumes.

  5. Trapped gases in the weld zone can form holes as the metal hardens.

  6. Changing filler metal is time-consuming since FCAW uses spools compared to some other processes that use short electrodes.

Important Points to Remember

Flux-cored arc welding is a versatile and efficient welding process, making it a better choice for some applications. It’s easier to learn, and the portability that it brings to the table makes it an attractive process.

FCAW is slowly replacing shielded metal arc welding (SMAW) in industries such as manufacturing and construction. The primary reason for that is automation wherein robots are taking over the assembly lines, welding with pin-point accuracy at any welding position.

We can definitely expect flux-cored welding to remain one of the more popular welding methods today, as continuous innovation further improves its efficiency and versatility.

Shielded Metal Arc Welding Described | Stick Welding

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Shielded metal arc welding is an electric arc welding system that joins metals collectively applying a consumable electrode. It was initial introduced in 1888 when Nikolay Gavrilovich Slavyanov applied consumable electrodes as a instrument to arc weld.

Shielded metal arc welding, normally identified as stick welding, continues to be to be one particular of the most frequently utilised welding methods these days. Stick welding is an immensely adaptable welding course of action, as we can use it in just about any industry, setting, place and metal.

Let’s even more dive into what differentiates stick welding from other welding processes.

What Is Stick Welding

Shielded metal arc welding (SMAW), also regarded as handbook metal arc welding (MMAW or MMA) is a welding system that takes advantage of a flux-coated electrode to join metals.

An arc sorts when the electrode idea comes into call with the workpiece. Fusion requires position as both of those the rod and workpiece melt, forming a weld pool from the molten metal.

Concurrently, the flux coating of the electrode is eaten, forming a protecting layer of shielding gasoline and slag in the weld spot.

Slag deposits will inevitably kind in the weld bead as the metals great down. The deposits in the weld metal can be chipped off making use of prevalent store instruments.

This handbook metal arc welding technique is limited to shorter weld stints, as the consumable electrode requires to be frequently replaced.

Shielded Metal Arc Welding System

Prior to welding, it is always recommended to check out the ailment of your devices. It is very important for the two basic safety and welding quality to have a nicely-operating energy resource, clamps, cables and electrode holder.

The next move is to pick an electrode that will enhance the base metal. Simultaneously, the electricity supply will have to be established in the good location: direct latest electrode adverse, direct latest electrode beneficial, or alternating existing. Just one wire in a stick welder is connected to the floor clamp and the other is joined to the electrode holder.

To commence the arc welding procedure, the base metal is struck with the electrode. A welding arc sorts as the electrode melts in the weld pool.

Consuming the flux coating releases a shielding fuel that safeguards the weld pool from atmospheric contamination. A regular arc duration should really be managed as the coated electrodes gradually be a part of the molten pool. Usually, the arc length must be roughly equivalent to the diameter of the main wire.

A layer of slag varieties as the weld metal cools. It can be taken off write-up-cleanup utilizing a chipping hammer and a steel brush.

Electrodes

a selection of different welding electrodes for shielded metal arc welding SMAW aka manual metal arc welding MMA

Electrode type is just one of the figuring out components in ensuring weld top quality. Its chemical composition can impact the arc stability, deposition price, depth of penetration and other variables. The electrodes appear at a mounted duration of 14″ (35cm) or 18″ (45cm) and the welder has to manually change them.

Stick welding electrodes are categorised into three key groups:

  • Cellulosic electrodes have a high cellulosic proportion in their coating which is appropriate for deep arc penetration and high weld speeds from its speedy burn up level. They can be used for any welding position, but the higher amounts of hydrogen have to be taken into account as it improves the possibility of cold cracking in the warmth-impacted zone (HAZ).

  • Rutile electrodes consist of higher quantities of titanium oxide (rutile) in the flux. This content can help promote lower spatter, a good bead profile and regular arc procedure. These electrodes can be applied in almost any welding placement and are usable in both of those AC and DC ability resources. They also make a fluid and viscous slag that is simple to remove.

  • Essential electrodes have significant quantities of calcium chloride and calcium carbonate in their coating. They are employed for welds that require excellent mechanical homes and resistance to cracking. Basic electrodes are acceptable for high weld speeds due to the fact the slag freezes quickly. This also arrives in helpful when welding in the vertical and overhead positions but in convert, the slag is more durable to get rid of, and consequently these electrodes are susceptible to make inadequate bead profiles.

On a different take note, metal powder electrodes have a flux coating with iron powder to encourage a higher welding latest. When compared to electrodes with no iron powder, metal powder electrodes have higher deposition prices and effectiveness.

Electrical power Source

Adhere welding can be applied in both of those alternating latest (AC) and direct present-day (DC) electrical power sources. The ability resource, no matter if DC unfavorable, DC good, or AC, really should be established relying on the form of electrode.

The welding equipment requires a frequent current, which is determined by the electrode sizing. The voltage will rely on the arc duration and rod composition and can be regulated by shifting the electrode closer or farther from the workpiece.

Products

Stick welding is normally the greatest option when welding thicker metals, when other strategies such as TIG and MIG welding are chosen for slender materials.

These are the products that you can stick weld:

  • Steel

  • Stainless steel

  • Chrome

  • Nickel-centered alloys

  • Iron

  • Moderate steel

  • Aluminium

Reactive elements this sort of as zirconium, tantalum, columbium, and titanium aren’t encouraged for this flux-cored arc welding procedure. The main purpose for this is that the shielding qualities are insufficient for security towards contamination.

Welding Machine

A ground clamp is wanted to avoid electrical shock. It demands to be connected to the workpiece or fixture. The ground clamp ought to be able of carrying the electrical present without the need of overheating to prevent dangers.

Welding cables made use of in SMAW are flexible and insulated. They should have a adequate cross-sectional region and size to carry out the welding recent with minimum voltage drop. There are two welding cables in a stick welding device, just one for the electrode holder, and the other for the floor clamp.

An electrode holder delivers the welding present to the electrode. It functions as a manual to precisely feed the electrode to the weld joint. Electrode holders change in measurement and possess distinctive latest capacities.

Shielded Metal Arc Welding Variables

Arc duration is one particular of the most very important things in adhere welding. Unique electrode materials and welding programs will establish the ideal arc length for the job. As a rule of thumb, the arc duration really should under no circumstances surpass the diameter of the core wire.

Amperage is motivated by the electrode range, welding angle and complete. There are amperage tips available in adhere welder manuals and guides.

Vacation speed is affected by the electrode angle and variety. For illustration, a fast filling electrode could let you to have a increased journey pace. Changing the travel pace improperly may possibly depart a frail and shallow weld, considering the fact that the deposits shaped may be extra or much less than necessary.

Welding Techniques – As opposed to other welding procedures, the SMAW welder has extra affect than the machine in figuring out the weld high-quality. Listed here are some of the styles and tactics that are suited for different assignments:

  • Whipping the electrode operates greatest on reduced-flux electrodes this sort of as E6010, E6011 and E6013 that can be trapped in the weld. Whipping will help to melt away and clear away contaminates from the ahead and again movement.

  • The circle procedure is largely used by newcomers considering the fact that it can create a regular journey velocity and is effective with most electrodes. Simply just go ahead a little bit with each and every circular motion.

  • Weaving is generally utilized when wider welds are expected. It is executed by going the electrode side to side following placing the arc.

Welding Positions – Stick welding is one of the most multipurpose welding procedures and it can be performed at different angles, which include flat, horizontal, vertical and overhead welding positions.

Safety Specifications

On any welding project, basic safety processes need to be followed. Carrying a appropriate welding helmet and gloves, possessing very good ventilation and a floor clamp current are usually all prevalent sense but in addition, don’t neglect to have the right understanding.

Remember that it is simpler to substitute or repair a piece of products than to threat hazards these as a flash burn off or bodily injuries.

Strengths of Stick Welding

  1. Stick welding can be performed in just about any surroundings.

  2. Machines is fairly affordable and inexpensive.

  3. Straightforward to use in tight spaces.

  4. Numerous obtainable electrodes to select from.

  5. Metal surfaces do not have to be cleaned as rigorously as for example in TIG welding
  6. Can be applied for a variety of metals and alloys, along with unique positions.

  7. Moveable and light-weight equipment, no need to have to carry a gasoline tank all-around.

  8. Gases developed are enough for preserving the weld metal.

Down sides of Adhere Welding

  1. Leaves spatter and slag deposits.

  2. Produces harmful fumes.

  3. Metal electrode requires to be replaced continually and electrode stubs go to waste.

  4. Tough to weld slender components.

  5. Time-consuming as it is a handbook course of action.

  6. Calls for talent and training to accomplish clean welds.

  7. Not appropriate for reactive metals.

Programs of Adhere Welding

Shielded metal arc welding SMAW working in heights

Routine maintenance and Restore

Stick welding is adaptable and hugely cellular, which makes it great for swift repairs, even in harsh disorders. A adhere welder can be made use of in windy ailments, rain and underwater, devoid of compromising its weld quality. Adhere welding’s distinctive trait is that it can weld unclean or rusty metals.

Fabrication

Given that shielded arc welding is fairly simple to master and welding gear is inexpensive, it is however one of the most common approaches in fabrication and construction. While some industries are shifting to a lot more automatic welding strategies, lots of nonetheless favor to use stick welding.

Vital Factors To Keep in mind

Shielded metal arc welding is a flexible process that can weld a assortment of metals. It is a fairly clear-cut course of action to learn and it can make higher-excellent welds.

Even though this strategy is 1 of the oldest forms of welding, innovations continue to make improvements to its effectiveness.

As of currently, stick welding continues to be to be 1 of the most reliable welding strategies out there, particularly if it is carried out by experienced men and women.

Solar Electric power Turns into New Energy Source For Alpha Production

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Top sheet metal manufacturing organization, Alpha Producing, element of The HEX Group, has accomplished the installation of 1770 photo voltaic panels covering 3,570.5m² of roof space at its manufacturing facility in Hixon, Dublin.

The photo voltaic panels on the Alpha Manufacturing roof will enable the enterprise to produce enough electrical power to run its equipment as extended as the solar is shining! Over 12 months, the organization will help you save 150 tCO₂e carbon emissions, the equal of a two-litre diesel auto travelling 1 million miles, and taking us a stage nearer to attaining our carbon neutral commitment by 2037.

As a renewable electrical power supply, solar energy is the Earth’s most considerable electricity supply and totally free. Formally identified in 1839, photo voltaic strength was 1st made use of in the 7th Century, but it is only now that we are starting up to recognise the value-saving positive aspects and the constructive effect it has on the atmosphere and international warming.

Did you know that there is ample solar vitality hitting the Earth every hour to meet all of humanity’s ability for the complete calendar year?

In the coming many years, The HEX Group plans to develop a 4-acre field around the site and put in a solar farm building one megawatt of electric power for battery storage. This, put together with the 735 kilowatts already fitted, will make us an off-grid corporation.

Electrical Discharge Machining | EDM Process Explained

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Electrical discharge machining is a non-contact fabrication process where the desired shape is achieved by using electrical discharges. Engineers often have to turn to EDM whenever traditional machining methods have reached their limits.

Since the dawn of the industrial revolution, our process capabilities have limited the design of our products. The first thing we verify after and sometimes during the product design stage is whether the selected manufacturing process matches our desired specifications.

Electrical discharge machining (EDM) changes that fundamentally. Unlike regular processes such as casting, forming and other conventional machining processes, EDM can achieve very high levels of perfection using digital inputs.

In this article, we’ll explore the EDM process and its various types. We shall also discuss its various benefits and limitations. Continue reading for a deeper understanding of the different EDM processes and to figure out which one is the best for your needs.

What is Electrical Discharge Machining?

Electrical discharge machining is a heat-based subtractive manufacturing process. It converts electrical discharge into thermal energy that melts or vaporizes excess material from a workpiece.

The process manipulates this erosion to create desirable cuts and shapes out of the raw materials. Due to the use of an electrical discharge, this process is also sometimes known as spark machining.

Since the process is based on the conduction of electricity through the material, it only works with materials that are good conductors. The process is incredibly reliable in delivering high-accuracy cuts regardless of a material’s hardness or softness as long as it has good electrical conductivity.

As a result, we can use EDM to cut high-hardness materials such as Inconel and tungsten carbide. Engineers also turn to EDM when they need to cut complex shapes that are not possible with traditional methods such as milling. Features such as sharp internal edges and deep cavities are exclusive to electrical discharge machining.

How Does the EDM Process Work?




Electrical Discharge Machining Working Principle

The process consists of two main parts: the electrode and the workpiece/material. Each is connected to one end of the power supply. The electrode carries one side of the charge and the workpiece carries the other side of the charge.

When the two get close, a white hot electrical spark jumps from the electrode to the workpiece due to the high potential difference between the two. This creates temperatures between 8,000 and 12,000 degrees Celsius in the spark gap which causes the material to melt and, therefore, erode. 

Such high temperatures necessitate the use of an insulating or dielectric fluid. The electrode and the workpiece are immersed in the dielectric fluid for the duration of the process.

The dielectric fluid controls the electric spark. It also acts as the process coolant and flushes away the tiny particles that are eroded in the process.

The eroded particles can have a size of 2 microns or smaller. For perspective, human hair has a thickness of 70 microns (+/- 20 microns). The eroded particles are so fine that they are comparable to the size of dust and smoke particles. Thus, we can achieve high degrees of precision through EDM.

It is important to note that the entire process is completely automated and CNC controlled. No human involvement. The process for a part can even be generated automatically from models created in 3D CAD programs.

Types of Electrical Discharge Machining Processes

Depending on the shape of the electrode and the process setup, we can achieve many different shapes and degrees of accuracy from raw material. Based on these, we can classify the EDM processes into three distinct types. These are:

  • Die sinking EDM

  • Wire EDM

  • Hole drilling EDM

Die Sinking EDM

The die sinking EDM process uses a die in the negative shape of the desired cut as the electrode. This die is brought in contact or ‘sunk’ into the workpiece in the presence of a dielectric fluid. This creates a negative impression of the die in the workpiece through a series of electrical discharges between the electrode and the workpiece.

Imagine pressing a metallic object into clay. The clay assumes the negative shape of the metallic object. The die sinking EDM process works the same way.

When people talk about electrical discharge machining, this is the process that is generally referred to. It is the conventional EDM process also known as cavity-type, volume, ram or sinker EDM.

In cavity-type EDM, the selection of the electrode material depends on the electrical conductivity and erosion resistance of a material. The higher they both are, the better. As a result, these electrodes are generally made of graphite or copper. Graphite is, however, easier to machine. The cost involved in machining the electrode can prove costly unless a higher volume of production can justify it.

With this method, manufacturers can create complex features (such as sharp internal corners) that are not possible via CNC machining services.

Wire EDM Machining



Wire EDM


Wire EDM

The wire EDM process uses a hair-thin wire instead of a die as the electrode for the process. The wire conducts the electrical charge to the material causing microscopic erosion of the material at desired locations.

The working is similar to the blade in a bandsaw. The wire goes through the material and makes vertical cuts in two dimensions. The diameter of the wire ranges from 0.05 mm to 0.35 mm.

The wire is usually made of copper or brass and is held between diamond guides. As the wire also burns during the process, fresh wire is constantly pulled from a spool during the cutting process to maintain the accuracy and precision of finished parts.

However, achieving sharp internal corners is difficult with this process. This is because the spark gap between the wire and the material creates internal corners with a small radius of about 0.15 mm instead of perfect perpendicularity.

Typically, the wire EDM cutting process starts from one of the edges of the workpiece. But starting the machining process from the center of a workpiece is also possible.

In this case, a hole is created in the center of the workpiece using a process known as small hole drilling EDM. Then, the wire is threaded through the hole and the cutting can begin.

Engineers use wire EDM to create incredibly complex shapes with extremely tight tolerances. If needed, wire EDM can be used to fabricate miniature parts for watches and other applications.

Hole Drilling EDM

Hole drilling EDM process uses tubular electrodes to drill small and deep cavities

Hole drilling EDM is a special type of EDM process that uses tubular electrodes to drill small and deep cavities into suitable materials. The working principle remains the same as in other EDM processes but the dielectric fluid is supplied to the machining site through the electrode itself.

Deburring accounts for a notable portion of the manufacturing costs. With hole drilling EDM process, there are no burrs which is a significant advantage over traditional machining processes.

Hole drilling EDM has very specific applications where intricate cavities are needed in a product. For instance, it has been instrumental in the design and manufacture of complex cooling channels in high-temperature turbine blades.

Electrical Discharge Machining Applications

Electric discharge machining is the best alternative to use whenever traditional machining methods reach their limit in machining electrically conductive materials.

An EDM machine can cut any conductive material regardless of its hardness or softness. As all metals conduct electricity to some degree, we can machine a long list of metals using EDM. Some of the materials that EDM is used for are copper, bronze, tungsten, steel (carbon, high alloy, stainless and hardened steel), Inconel, titanium, etc.

As far as industries go, EDM is finding applications in a wide range of them from automotive to aerospace. The use of EDM has been common for dental parts but is now becoming increasingly useful in prosthetic, implant and surgical tool manufacturing.

The unique characteristics of electrical discharge machining make it ideal for parts and features such as:

  1. Extrusion dies

  2. Injection molding tools

  3. Sharp internal corners

  4. Straight or curved small holes

  5. Rotary forms

  6. Engravings on hard materials

Advantages

Electro discharge machining provides many advantages over traditional machining methods. Some of these advantages are unique to EDM while others are found in newer methods such as waterjet and laser cutting. Let us take a look at some of these:

Greater accuracy

Electrical discharge machining provides one of the highest accuracies among modern manufacturing processes. A regular setup can deliver an accuracy of up to 0.025 mm but there are special EDM machines that can go up to 0.005 mm.

The accuracy for a specific part depends on factors such as the material characteristics, machining time and the degree of surface finish desired.

Complex designs

With EDM, it is possible to develop and manufacture extremely complex and intricate shapes. These shapes would be very difficult and even impossible with traditional methods.

Amazing surface finish

EDM cuts have zero-directionality and leave no machining marks unless the machining time is reduced below a certain threshold.

The high-quality finish is due to its slow rate of material removal. Only tiny particles are removed at a time allowing EDM to leave a smooth surface that does not need additional treatment for a satisfactory surface finish.

Wide range of workable materials

Due to most metals being good conductors of electricity, EDM works with a wide range of materials.

Non-contact process

There is no cutting tool involved in the EDM process. Thus, the workpiece is not subjected to any mechanical force or pressure. Even extremely soft materials that would normally be susceptible to damage or breaking by the pressure from the cutting tool can be machined through electrical discharge machining without any risk.

Disadvantages

No manufacturing process comes without its limitations. There are always trade-offs. The disadvantages of using EDM are as follows:

  • Electrode cost

  • High power consumption

  • Does not work with non-conductive materials

  • Formation of heat affected zone

Electrode cost

The tool electrode life is limited in EDM. It is susceptible to erosion like the workpiece. This can cause issues with creating features such as sharp internal corners as the tool life deteriorates over time.

It is recommended to replace the electrode regularly for dependable parts. The cost of electrodes affects the feasibility of the process depending on its complexity and rate of replacement. However, if the number of manufactured parts is high, this cost is absorbed to some extent.

High power consumption

EDM is a power-intensive process. It requires a high current at a constant rate for effective machining. The power system and the feed would need to be adjusted for different applications.

For instance, the die sink EDM uses a transistorised power system as it has lower tool wear. Wire EDM uses a transistor-controlled capacitive power system as it has a lower risk of wire rupture. Hole drilling EDM typically uses a capacitive power system due to its higher material removal rate and process stability.

The rate of consumption depends on the machining tool construction and the machining parameters. Typically, it is between 5 to 8 kW when machining AISI P20 steel.

Does not work with non-conductive materials

The process cannot work with poor electrical conductors. We cannot machine common materials such as plastics, composites and glass.

HAZ formation

Development of the heat affected zone can be a concern but the spread and the effect on the microstructure is far lower than alternative machining methods.

Research shows that the extent of HAZ development varies with the material. But in all cases, controlling factors such as the available amount of heat, its conduction and cooling action can considerably reduce HAZ development.

Actionable Design Tips for Your EDM Part

There are several things to keep in mind when you need to create an EDM part. The following tips will help you reduce the cost of your EDM part while also not compromising on the design.

  1. Wire EDM will leave some radius when machining internal corners. This internal corner radius is usually a little more than the wire radius because of the spark gap. The permissible value of this corner radius, therefore, determines the maximum wire diameter. A higher permissible value will allow for a thicker wire making the process faster.

  2. There can be some material exchange between the wire and the material in an EDM process. Galvanic corrosion can be a concern during post-machining cleaning if one is not careful.

  3. The vendor must be capable of providing fixtures that allow similar operation on multiple parts at once by stacking or multiple EDM operations on a single part for a lower cost.

  4. If possible, try to remove the majority of the wastage using traditional methods and use EDM only for the final operations as this considerably reduces the overall manufacturing cost and EDM machining time.

  5. Loosen the part’s surface finish tolerances as far as practical, this reduces the number of passes the manufacturer needs to fabricate the part. Rougher surface finish allows for increased material removal rate and higher current magnitude.

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