How To Control The Quality Of Electron Beam Welding

How To Control The Quality Of Electron Beam Welding

Electron beam welding is a vital art in many core industries. These include aerospace, oil and gas, and medical equipment. EB welding was invented in the 1950s, which was a time when fusion was very much in vogue. However, electron beams have stood the test of time in terms of their real-world applications. Being able to tightly control electron beams via the combination of a vacuum and precision calculations gives engineers formidable levels of control.

Through EB welding, metals can be bonded in a way that is safe and reliable. This highly specialised industry is all about precision and quality. This is all down to quality control, something that Electron Beam Processes value highly and that clients trust. To see what goes on behind the scenes, read on.

Visual Inspection

The surface of the metals is crucial in precision welding. In the same way that filling in a pot-hole and hoping for the best never works when combining ice and tarmac, metal quality makes a big difference in precision welding.

For metals, microscopic visual inspection is important. This can identify cracks and other flaws, and can help when calculating fatigue. Fluorescent dye is also used to flag tiny details. Knowing the quality of the surface ensures that bonds are entirely reliable.


When it comes to electron beam welding, the quality of the entire piece of metal is as important as the quality of the machine. Important issues such as fatigue cannot be ignored. In these cases, radiography can be a useful ally. Radiography can either be used as a sample measurement, or can confirm metallurgic suitability.

Ultrasonic Testing

Sound-waves are an excellent detailed visualisation tool. This non-destructive method of quality checking is a highly effective way to explore the deep structures of a metal or joint.

Ultrasonic testing (UT) can identify invisible cracks and uncover tiny defects. UT is also valuable for its ability to give precise readings in testing. This is required by many industries that rely upon predictable and measurable quality levels.

Batch Control Testing

These are a form of quantitative testing. They allow a weld to be meticulously dissected into macro and micro quality control pieces at any point during production. Batch control gives a good overview of an entire run. Carrying out detailed dissections on a small number of dummy parts means that overall quality can be established.


Reliable Results Each Time

Superior testing is one of the features that has given EB welding its global value. At Electron Beam Processes, we have built a reputation for rigorous testing, reliable results and extremely tight quality controls. For more information about the EB welding process, how we test, and what you can do to ensure that we are working with the best materials, please download our free guide. Or, you can send any questions to [email protected].

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Why Does Electron Beam Welding Need A Vacuum?

Why Does Electron Beam Welding Need A VacuumThe electron beam welding (EBW) process is a method of melting metals together to form a joint. A powerful and highly accurate beam of electrons is fired at the joint, causing the material to melt and then re-solidify to create the weld zone. If there is one word that comes to mind when EB welding is mentioned, it’s vacuum. There are three main reasons that a vacuum is used.

1) The Prevention Of Oxidisation

The combination of heat, atmosphere, and metal carries with it the risk of oxidisation. Some metals – such as iron – are more at risk of oxidisation than others, but any alloy is vulnerable. The result is metallurgical disturbance and a weaker joint, rendering the weld unsuitable for many of the applications that EB welding is traditionally used for.

2) Atmosphere Is Heavier Than Electrons

Atoms such as nitrogen and oxygen are heavy. Electrons weigh less than 1/10,000th as much. Firing electrons through a dense atmosphere leads to collisions, interrupting the beam and wasting energy. This is realised as a loss of heat, a softer beam, and a weaker weld.


3) Avoiding Electrical Arcs

Extremely strong electric charges are required to create a powerful electron beam. Arc welding uses this – albeit on a much smaller scale – to its advantage. However, the electric potential used in EB welding is so high that there is the risk of generating an uncontrolled ‘lightning’ effect. These have the capacity to damage both the weld and the electron gun.

Given that each of these are major considerations within the EB welding process, the idea of removing the vacuum seems like a strange one. Despite this, if the vacuum could be removed, the potential for single pass thick section welding of large components becomes a possibility.

Non-Vacuum Welding

The development of non-vacuum welding (NVEB) has focused upon addressing the problems – oxidisation, atmosphere, and arcing – that the vacuum traditionally solves. However, to date, the technology is in an early stage of development.

The problem of the atmosphere causes inevitable scattering. As a result, both the weld depth and the column distance have to be greatly reduced to achieve any kind of reliable weld. To date, NVEB welding has only been successful at a maximum column distance of 30mm and maximum penetration of 50mm. Various attempts have been made to introduce features such as plasma control, but – ultimately – laser welding offers a much more satisfactory result.

This does not mean the end of the road for NVEB. Experimentation continues, and the industry is watching with interest.

The Verdict

Many of the features of electron beam welding are only possible because of the vacuum. Precision, single-pass, and quality guarantee each require the removal of interfering agents such as oxygen. The idea of non-vacuum welding is perhaps plausible, but there is a long way to go. At Electron Beam Processes, we only ever work with the tried-and-tested vacuum. To find out more, download our free guide to best practice.

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How Is EB Welding Used In Industry?

How Is EB Welding Used In Industry

Electron beam welding (EBW) has many applications and uses. As demands for precision technology grow, so too does the uptake of EBW in a range of sectors.

Which Industries Rely Upon Electron Beam Welding?

EBW involves creating the correct conditions for movement of electrons. When channelled, the electrons form a finely-focused energy beam with a strong enough power density to melt metals. These re-bond into a reliable joint.The process is valued because the weld can normally be achieved without filler and in a single pass, and with minimal metallurgical disturbance. This increases strength and reliability, whilst offering significant productivity increases.

Therefore, EBW has many applications for industries that require strong, reliable joints for complex parts. These include:

1) Aerospace Manufacturing

Flight-critical components which almost always require welding will encompass EBW. The method offers low distortion, which ensures accuracy when working with exotic alloys such as titanium and nickel alloys. The sterile vacuum prevents the risk of oxidation that could weaken the joint, resulting in intricate components that have high resilience to engine vibrations. EBW is also widely used to join new components to existing parts. Examples include:

  • Critical rotating parts
  • Bellows asemblies
  • Combustion chamber
  • Blades and nozzle guide vanes
  • Bearing assemblies (with dissimilar materials)
  • Gear and shaft assemblies
  • Component salvage and repair

2) Automotive/Motorsport

EBW is used in many elements of automotive engineering. EBW is able to successfully join the complex array of metals – such as low carbon steels, micro alloyed steels, titanium alloys, and medium carbon steels which have a carbon content of 0.3% and lower. Parts and assemblies include:

  • Clutch housings
  • Gear assys
  • Spur gears
  • Suspension members and mechanical linkages
  • Torsion springs and roll bars
  • Bearings and drive shafts
  • Pressure bottles
  • Lip seals (welded with seal in place)
  • Turbine impellars to shafts (dissimilar materials)

3) Defence

Defence contracts involve some of the most dynamic design demands. EBW is attractive due to its suitability for use in transmission assemblies. Machine-finishing and hardening is carried out ahead of the welding process, and the use of EBW at the end of the process means that distortion is minimised. For defence and similar industries, highly complex projects can be successfully fabricated. Examples include:

  • High strength equipment enclosures
  • Underwater and space pressure vessels
  • Heavy duty structures
  • Titanium fuel cells
  • High pressure pneumatic and hydraulic vessels
  • Missile casings and launchers
  • Radar wave guides and antennae
  • Flight data collection cases which need to be crash survivable

4) Medical Equipment Manufacturing

The autogenous capabilities of EBW – which allow welding without needing to introduce a filler material – ensures the biocompatibility of the part. EBW is used for medical instruments, surgical tools, and implantable devices. Examples include:

  • Spinal implant devices
  • Finger and knuckle implants
  • Invasive growers
  • Replacement hip and elbow joint

5) Oil & Gas

Hostile environments require corrosion, pressure, and stress resistance. EBW responds to this challenge due to the pin-point beam, which minimises the zones affected by the welding heat. Combined with the single-pass process, this results in high weld integrity. Sample parts include:

  • Electrical measurement equipment
  • Pressure sensors
  • Temperature sensors
  • Pipeline connectors
  • Seismic sensors
  • Turbines
  • Drilling systems
  • Stator and rotor assemblies

6) Power Transmission

Power transmission involves complex assemblies with dissimilar materials. Assemblies have to be able to withstand vibration and heat. Examples include:

  • Gear-to-shaft and coupling-to-shaft assays
  • Synchros-to-gears
  • Spur gear assemblies
  • Herring bone double-helical gears
  • Fluid couplings
  • Epycyclic sun gear and planet gear assemblies
  • Shaft-to-impellor (dissimilar materials)
  • Drive couplings

7) Nuclear Power Generations

This industry requires exceptional quality control and best practice procedures to be endorsed.

Typical applications for EB welding within this sector are: Fuel Rods, Heat Exchangers & Nuclear Waste Containers.

Learn More

The demand for manufacturing innovation has never been higher. As companies seek ways to reduce energy consumption, increase efficiency, and create new solutions to advanced challenges, EBW has maintained its position as a reliable, cost-effective solution. We are certified above the industry standard in each of the main EBW sectors, and have an extensive portfolio of parts and assemblies. Download our free Best Practice Guide today to learn more about EBW benefits. Typical applications for EBW within this sector are fuel rods, heat exchangers, and nuclear waste containers.

What Is Electron Beam Welding?

What Is Electron Beam Welding

Put very simply, electron beam welding (EBW) is a process whereby two metals are fused or welded together using a beam of high-velocity electrons. This type of welding is suited to applications requiring high-precision, very good repeatability and high-strength.

Electron beam welding is carried out in a vacuum atmosphere to ensure that the beam of electrons are consistently in a stable condition and thus preventing any dispersion before they reach their target – the work piece.

Key Differences Between EBW & Arc Welding

In traditional welding methods such as arc welding heat is generated using a strong electric current which passes through a consumable cathode. This method is very resource intensive and not suited when precision welding is needed and/or sensitive metals are used.

The extreme heat generated by the arc welding process can cause the metal to distort and bend out of shape. By contrast, electron beam welding creates just enough heat in a very localised area to fuse the two metals together across the join. The level of precision that can be achieved with this welding technique is unrivalled.

There is also a significant difference in the complexity and cost of the machinery used in EBW. When asking what EBW is, it is important to understand the differences in machinery required to perform electron beam welding.

Electron beam welders operate under vacuum conditions and because of that they are not portable and can only be used in one static location. Arc welders are portable and can be used out in the field or on a production line. Electron beam welding machines are often used for welding in the aerospace industry or other highly technical applications.

The Cost of Electron Beam Welding

Due of its complexity, electron beam welding is deemed to be more expensive than other forms of welding and is generally only performed by specialist engineering companies.

Arc welding is much less expensive and is the direct welding method of choice when it comes to cost. The high level of precision that EBW can achieve is one of the reasons why it is widely used despite its higher cost. The biggest cost involved in EBW is the initial capital outlay to purchase the required machinery. For this reason most companies outsource their EBW needs unless they use this type of welding on a regular basis.

The total cost of ownership related to EB welding equipment is a consideration which needs to be thought through carefully. The cost of purchase is not the only factor that needs to be taken into consideration, there is also the associated costs of training operators; this can be a long drawn out process because this type of welding is deemed to be very knowledge biased.

Access The Benefits Of Electron Beam Welding

Our company specialises in electron beam welding at what we deem competitive prices. We have over 50 years of experience welding applications which require a high level of technical expertise, putting us at the forefront of electron beam welding technology. In addition to this, we also offer several other services that complement our EB weld offering.

EBP Ltd are industrial members of TWI – The Welding Institute – where we have a huge amount of technical knowledge, advice, support and assistance ready to share with you and subsequently ensure that your needs can be catered for.

Please get in touch to find out more.


Electron Beam Welding: Advantages & Disadvantages

Electron Beam Welding - Advantages & Disadvantages

Electron beam welding (EBW) is a metal welding technique which takes place in a vacuum chamber using a beam of high energy electrons to heat the metal. This melts the material, creating a ‘keyhole’ which then solidifies as it fuses with another component. EBW is known for its precision, making it a popular choice for the Aerospace, Defence, Medical equipment and Medical Implant manufacturers, the Motorsport Industry, Nuclear industry, Oil-and-gas Industry, the Space Industry and many Instrumentation applications. Here are some of the advantages and disadvantages of EBW.

EBW is one of a range of options that EBP Ltd offer to our customers, which also includes Tungsten Inert Gas welding (TIG), as well as Non-Destructive Testing, CNC machining and Heat Treatment.

Advantages of Electron Beam Welding

1) A clean process as it is carried out in a vacuum chamber:

EBW is free from potential gas contamination as the welding is done in a vacuum chamber, resulting in a high-quality weld with no oxidation.

2) Good for delicate assemblies:

Since EBW uses localised heating (small Heat Affected Zone, or HAZ) and has minimal heat input, the surrounding material stays cool. This allows for welding of delicate products and close to heat sensitive areas such as populated electronics enclosures. EBW has a HAZ similar to laser beam welding, which is less than 5% of a similar TIG weld.

3) High quality and integrity from machine-controlled automation:

EBW has high strength with minimal distortion or damage. Also, very little post-weld machining is needed due to its accuracy, making it suitable for welding precision parts. Since the machine is programmable, it is possible to have custom weld-profiles. Our quality is assured through AS9100 Rev D, AS9104 and NADCAP certification as well as bespoke OEM approvals.

4) Repeatable accuracy and quality control:

Precise parameters can be machine-programmed to reproduce welds in large quantities whilst maintaining accuracy.

5) Joining dissimilar materials:

One of EBW’s greatest advantages is its ability to weld materials with different melting points, such as copper to stainless steel. From a cost and performance perspective EB welding also has the ability to weld high-cost nickel alloys to relatively low-cost stainless steel.

For example, the corrosive performance of a nickel alloy which is only required in a particular area within a product’s design, can be EB welded to a low-cost stainless steel which is not subjected to the same corrosive environment which the nickel alloy is. Heat-treated components can be EB welded as can highly reflective metals such as platinum. Refractory metals such as titanium can also be EB welded.

6) No filler material used:

Typically, no filler materials are used in the EB welding process. It is the parent material which is melted to create the join and thus the assembly.

7) Range of penetrations:

A variety of weld penetrations are possible, from 0,005” (0,127mm) to 2” (50mm). It also has a high depth to width ratio (10:1 to 40:1 in many cases).

8) High welding speeds:

Although EBW has a longer cycle time than laser beam welding, it achieves high welding speeds of up to 30mm per second.

9) Cost Savings:

EBW is a cost-effective method of welding, only requiring a single pass of the electron beam, unlike TIG, MIG and arc welding which tend to endorse multiple passes of the heat source.

The EBW process can also deliver weight savings if the products design allows for this, which can then lead on to further benefits such as a reduction in lead time and inventory costs.

Disadvantages of Electron Beam Welding:

For a balanced overview let’s look at a few reasons why EBW may not be suitable…

1) Setup costs:

The initial outlay for equipment is expensive. With these costs in mind, a company will need a large work-flow in order to justify the investment. It is usually more cost effective to outsource your EBW requirements unless you have a large volume throughput over a long period of time.

2) Equipment:

Due to the complex technical equipment, expert operators are essential. If you are starting with a clean piece of paper, you will need to invest in professional training and employ experienced qualified welding engineers.

3) Size limitations:

The size of the components to be welded is limited by the size of the vacuum chamber at your disposal.

4) X-Rays & Radiation:

Safety standards are exceptionally strict as x-rays and radiation are both present during the welding process.

Making the Right Decision

When considering the advantages and disadvantages of different welding options, it is advisable to consult experts to help you make the correct decision.

From the design concept through to the manufacture of the detail parts and then onto the product assembly, the post weld testing regime, through to the technical support; align all of this with a world-class company infrastructure. Our team at EBP Ltd have the equipment, knowledge and the skills matrix to offer a single point solution.

Please call +44 (0) 1483 215401 to find out more.


Why Is EB Welding Done In A Vacuum?

One of the distinguishing features of EB welding is that it requires a vacuum to be successful. Why is this?

The Electron Beam Welding Process Explained

1) Prevents Beam Dissipation

The Electron Beam is a focused stream of electrons of tiny mass but travelling at incredible speed. When a supercharged electron collides with a comparatively huge oxygen or nitrogen atom in the air, it careers off at an angle. This scatters and dissipates the beam deflecting energy and defocusing the beam. To ensure consistent weld quality and weld profile a vacuum of 10 ppm or better is required.

2) Prevents Oxidation

Under normal atmospheric conditions, many commonly used metals – including steel – will oxides (rust). Many high performance materials such as Titanium and high strength heat resistant metals are unusable if exposed to air at high temperatures. As EBW is mainly a process of melting the abutting faces of the components, without filler material, this is a remelt of parent material in a vacuum, resulting in parent metal integrity.

The vacuum chamber used by electron-beam welding machines provides a fail-safe, belts and braces approach to this problem by removing all air surrounding the component. It isn’t only EB welding that has to deal with the problem of oxidation. Tungsten Inert Gas (TIG) welding shields the seam with a blanket of inert argon or helium to prevent oxidation until the melted material cools.

3) Damage Prevention

To accelerate the electron-beam to the required speed, the electron-beam generator uses an extremely strong electric field. In normal air, the charge is so strong that it risks creating electric arcs – in effect miniature lightning bolts – from the beam emitter. This reduces the control the operator has over beam intensity and can lead to erratic results. More importantly, the lightning arcs can severely damage the welding machine and component. The vacuum is essential to maintain stable beam control.

When Does EB Welding NOT Require A Vacuum?

Electron beam welding always requires a vacuum, except when it doesn’t! In some circumstances a non-vacuum electron-beam welding machine may be required. In these units a series of pressure chambers are used in place of the single vacuum chamber, in order to project the beam through the air with neither heat loss nor arcing.

This may be necessary when working on marine or offshore applications, or in the presence of sensitive materials, such as nuclear waste and petrochemical products.

Weld outcomes for non-vacuum EB welding are almost identical to those expected for vacuum machines, although the power output required to achieve the same weld penetration is slightly higher for non-vacuum machines, and the weld speed is lower.

Download Our FREE Best Practice Guide

Our team at Electron Beam Processes Ltd make us Europe’s leading EB welding specialist. To support businesses through the process we have made a Best Practice Guide available, which can be downloaded for free by clicking here. For all other questions please call +44 (0) 1844 241 4257.

The Electron Beam Welding Process Explained

The Electron Beam Welding Process Explained

Electron Beam Welding (EBW) is one of several methods used to weld metal components together. It differs from other processes in several important ways, which will be explained in this article. EBW has unique abilities for welding dissimilar metals, complex or curved components and precision parts.


The main advantages of electron beam welding are:

  • High weld strength
  • Fast cycle time
  • Little to no distortion
  • Consistent weld quality
  • Small heat zone with very little heat dissipation
  • Variable weld depth
  • Precision CNC control

Clients report reliably good results from using EBW on a broad range of projects. However, the success of a weld depends not just on the method itself, but on design, surface preparation and applicability to the specific project. This is an important decision, so it is worth briefly examining how EB welding works, the requirements for success and how the process differs from common alternatives.

How EB Welding Works

EB welding fires a high velocity beam of electrons at a weld joint – usually within a vacuum chamber.

The electron-beam is generated by an electron gun: constituting a high voltage power supply that feeds energy into an incandescent cathode, which in turn expels high-speed electrons. The beam is then focused and accelerated through a series of anodes and a focusing coil – which concentrates the beam by means of an electri0-magnetic field.

The energy intensity of EBW is 100-1000 times greater than Arc welding, as a result the beam vaporises a hole into the parent metal resulting in a deep, narrow weld and a weld speed 10-50 times faster. This also produces narrow Heat affected Zones (HAZ) and very low distortion.

The Electron Beam position is normally fixed and the components moved under the beam by conventional rotary and linear movement systems, with power and weld speed controlled by programmable systems.

There are many different varieties and sizes of electron-beam welding machine, but most follow a similar operating process:

1) The two parts are cleaned thoroughly to remove contaminants and demagnetised if ferrous based metals. This ideally should be done by the welder or contractor.

2) The parts are secured to their fixtures and attached to the welding machine’s CNC operated work movement system. This can be programmed to manoeuver the parts into position and make adjustments during the process.

3) The vacuum chamber is sealed and a vacuum created by expelling air from the chamber. Some materials, e.g. Titanium, require a higher level of vacuum for welding

4) The electron beam is aligned with the joint then generated to the appropriate power. Beam parameters can be manually or CNC adjusted during the cycle to maintain consistent weld quality.

5) The electron beam welding cycle is initiated. 

6) After welding is complete, the vacuum chamber is re-pressurised, so it can be opened and the joined part removed.

7) Fixtures are removed, after which the part is subjected to a thorough inspection process. Non-destructive Fluorescent Penetrant crack testing is the most common quality control method. This is often used in tandem with visual inspection and/or radiography.

Requirements For Electron Beam Welding

For electron beam welding to be successful it should meet certain base conditions:

  • EB welding works with a wide range of metals; including high and low carbon steel, stainless steel, most nickel and copper alloys and titanium. It can be successfully used to join two dissimilar metals: however, aluminium and other refractory metals exhibit variable results when joined to other metal types through EB welding.
  • As electron-beam welding does not use filler material (in most circumstances), close attention should be paid to the joint design. The best joints have either planetary or circumferential configurations. Most designs are compatible with EB welding but it is critical that the fit requirements of the joint are taken into account at the design stage to ensure the closest abutment.
  • EBW is a machine based process, usually samples representative of the production part are required to establish and demonstrate weld results. These settings can then be used for any future production requirements.

Alternative Welding Methods

The most commonly used alternative to EB welding is arc welding, where the weld area is melted by an electric current, leaving an arc of molten metal on the surface. This is a versatile process but can be slow and requires a lot of energy – usually with a dedicated power supply for each welding unit. Furthermore, the heat generated by arc welding sometimes has negative effects, affecting nearby components and warping the joint itself. Arc welding also requires stringent health and safety measures to protect operators from light, extreme heat and inhaled metal particles.

More Free Information

The approach you need to take with Electron Beam Welding depends considerably on the metals you work with, the component design, joint preparation and other factors. All these are covered in depth in our free Best Practice Guide.

For more information, please speak to one of our experts today by calling 0844 241 4257, or emailing [email protected].

Electron Beam Welding Vs Laser Welding

Electron Beam Welding Vs Laser Welding

Electron Beam Welding (EBW) and Laser Beam Welding (LBW) and are both fusion welding techniques that use a high energy density beam to melt the joint of two components. Both methods have fast cycle times and produce high weld quality. They are similar and can be used side-by-side in some circumstances, but they are not identical.

What Is Laser Welding?

Laser Beam Welding uses a concentrated beam of light to affect the weld. LBW machines are highly automated and are generally linked to Computer Aided Manufacturing (CAM) design routines. Lower to Mid-range power Solid State (SS) lasers can be delivered by fibre-optic cable and are therefore suited for robotic welding applications.

The laser beam can be directed along the joint by laser scanning, allowing a greater weld speed and versatility for robot systems. Although SSLB can be conducted in air, shielding gas must be used to get good quality results, particularly in high strength materials.

The advantages of SSLB welding are faster weld speed than arc welding, with lower heat input and less distortion, they can weld in air and have no radiation risks.

The disadvantages include problems weld materials with highly reflective weld pools, such as Aluminium or Copper, very small focal range requiring accurate weld height control and weld gas shrouding at high weld speeds.

High powered Gas generated LB cannot be delivered by fibre-optic cable and must be delivered via solid glass rods and prisms, resulting in a stationary weld point in most cases. At this point there is a cross over with EBW.

What Does EB Welding offer?

Low voltage EBW (up to 60Kv) can be applied to a moving EB gun with automatic joint tracking and does not have radiation issues, however welding for high quality welds will still be done in a vacuum chamber.

For EB welds filler material is rarely used. The weld is therefore a re-melt in vacuum of the parent material(s) resulting in consistently high quality.

The energy density of High Voltage (60-200Kv)EBW is substantially greater than LBW, and as a result is used for the most critical applications where it produces higher weld speeds, greater weld depth, narrower weld bead and lower distortion.

All modern EBW equipment is fully computer controlled for weld power, focus and work piece movement. Weld data is captured in real time for quality control purposes.

In a gas laser welding machine, the laser beam is channelled through a CO2 gas chamber, generating a longer wavelength beam of 10 µm or more – falling within the infrared spectrum. These machines can generate either continuous delivery or pulse beams and allow a higher power output than solid-state laser welders. The laser is delivered to the join by means of a crystal lens, as the heat of the beam would destroy a fibre-optic cable. 

Find Out More

Electron Beam Welding is one of the most reliable welding methods for complex parts and dissimilar metals, but it still requires careful design consideration to achieve optimum results.

Incorrect joint design, unsuitable material specifications and contamination can all affect your final result. Also, other welding methods, such as laser or arc welding, could be more appropriate for some applications.

To find out more, please download our Best Practice Guide – a free resource that sets out the design, fabrication and testing practices that deliver the best results from EB welding.