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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.

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