Plasma Hardfacing

Plasma Hardfacing – The Complete FAQ Guide

Many people still do not know what plasma hardfacing is. You might even be perplexed as to what it is.

This is perfect because in this guide, we will discuss everything you need to know about plasma hardfacing.

From what it is, what techniques are involved, and where you can get equipment for it – we’ll cover it here for you!

Understanding Plasma Arc Welding (PAW)

Plasma arc welding, is a welding process where the electrode is within the torch’s body.

You can find it similar to Tungsten Inert Gas (TIG) welding; and the only key difference is with the location of the electrode.

What this does is it separates the shielding gas envelope from the plasma or the electric arc.

What is Hardfacing in Welding?

Hardfacing is a metalworking procedure where you strengthen a base or a parent metal through deposition of tougher and harder materials.

Oftentimes, you’d apply wear plates and other thick coatings to base or parent metals. This is to improve and enhance durability, resistance, and lifespan.

What is Plasma Hardfacing?

PTA or plasma transferred arc hardfacing is a process of depositing tough materials to base metals using plasma.

Plasma hardfacing utilizes plasma powder, melts it, and uses the heat from the arc to complete the deposition.

Once the area heated cools down, you’ll see that the outside layer has been formed.

What are the Different Hardfacing Techniques?

You can accomplish plasma hardfacing by utilizing a bunch of techniques and processes.

But, the most common ones include:

Welding Processes

There are many welding processes you can do to complete hardfacing.

You can choose to utilize plasma transferred arc welding (PTAW), oxyfuel welding (OFW), submerged arc welding (SAW), and many more!

Spray Fuse

Out of all hardfacing processes, spray fuse is known to be the most common.

In spray fusing, you’ll force metal alloys via a gun type of torch; the powder will be molten and will be deposited to the part or component.

Thermal Sprays

Unlike spray fusing, thermal sprays join two elements together mechanically. The material you’ll add would not pass through high heat.

Those are the primary procedures of hardfacing; there are others, but those are the most common.

Applications of Plasma Cladding or Hardfacing

You can use plasma hardfacing or cladding in a lot of applications.

However, the typical uses you can have for it include the following:

• Engines (automotive, aircraft, marine, etc.)
• Valves and valve seats
• Chutes and liners
• Power and generation industry
• Welding and fabrication
• Pressure tanks and vessels
• And many more!

What are the Advantages of PTA Hardfacing?

You can get a ton of benefits in doing PTA hardfacing over the usual welding processes.

Some of these advantages include, but are not limited to:

Easy Automation

PTA hardfacing can easily be automated; giving you better chances of replicating the same result over and over again.

Wide Range of Material Capability

Unlike thermal sprays, plasma hardfacing is applicable to more types of metals and alloys.

It’s a lot more compatible than sprays and it sticks better to a myriad of substrates.

Better Control

You will be able to maneuver it better with much more control; you’ll be able to toggle the heat input, amperes, powder feeder rates, etc.

Smoother Deposits of Material

Plasma hardfacing can give you a better guarantee that the deposits will be smoother.

Because you’ll be able to control it better, there’ll be less post-weld procedures.

These are just some of the benefits of plasma or PTA hardfacing; there are others, and they’ll depend on what you need it for.

Welding Rods Used For Hardfacing

For hardfacing, the welding rod you’d have to use will depend on the results you’re looking for.

There’s a specific type of welding rod for restoration and recreation, and there’s a particular type for wear and corrosion resistance, for durability and strength, and so on.

What Welding Electrodes Can You Use With Plasma Hardfacing?

Akin to welding, you can use a wide range of electrodes for PTA hardfacing.

You can use stainless steel electrodes, carbon steel electrode, wires, powder form electrodes, and so on.

The most common type of material to deposit in PTA hardfacing, though, would be powder.

What is PTA Welding?

PTA, or Plasma Transferred Arc Welding, is a welding process that uses a tungsten electrode to create a high-density arc.

In most cases, it’s the welding process you will use for hardfacing on mechanical surfaces.

What are PTA Welding Equipment?

PTA Welding Equipment are the machineries or equipment used for PTA Welding.

These are the types of machines you need to use to perform hardfacing or cladding to your machines.

The most common parts or units PTA welding equipment has include:

• Column & Boom
• Powder Feeder
• Water Chiller or Recirculator
• Power Source
• Weaver or Welding Oscillator
• PTA Torch
• Welding Positioner
• Process Control Panel

What is the PTA Process?

It’s a liquid-state welding process, where the metal-to-metal joint forms into a molten state.

In the process, you use the hot ionized gases to heat the workpiece or the surface. Due to the heat, fusion happens and the weld is completed.

What is Plasma Arc Welding (PAW)?

Plasma Arc Welding or PAW is a welding process almost the same as the PTA.

They use the same method but differ on the materials utilized.

The difference is with the filler material you will use:

• PAW uses filler metal in wire form
• PTA uses filler material in powder form

What are the Fields of Application of PTA Welding?

Whatever industrial sector you are in, you can greatly benefit from PTA Welding.

The most common applications you can have for it include, but not limited to:

• Forging of Matrix Dies and Moulds
• Making Corrosion or Abrasion Resistant Industrial Equipment
• Improvement of Automotive, Petrochemical, and Marine Valves
• Enhancement of Lamination Rollers and Rollers
• Enhancement of Cutting and Milling Tools
• Development of Parts for Nuclear Plants
• Developing Industrial Cutters and Blades
• And Many More

What are the Advantages and Disadvantages of Plasma Arc Welding?

Plasma arc welding has a ton of advantages, some of which include:

• High Rate of Deposition
• High Heat Concentration
• More Freedom to See and Observe the Weld
• Low Pollution
• Less Expensive or Costly
• Controlled Penetration

Apart from that, though, it also has certain disadvantages, which are:

• Generation of Smoke and Noise
• Difficult to Make Sharp Corners
• Wider Heat Affected Zones and Weld Areas
• Produces Infrared and Ultraviolet Radiation

What is Plasma in Welding?

In welding, the hot ionized gas that forms in the process is called the plasma.

Plasma is formed due to the ionization of Argon that passes through the electric arc.

Is Plasma Safe?

Yes, plasma is safe to use and it’s not different from other compounds.

But, just like others, there are precautionary standards you have to follow.

What is Plasma Welding Used For?

Generally, you would want to use plasma welding if you want to achieve the following:

• Better Control and Quality of the Output
• Cleaner, Smoother, and More Specific Designs
• Higher Heat Tolerance
• Lower Cost of Welding

What is TIG Welding?

TIG is short for Tungsten Inert Gas Welding.

It is a type of welding that produces the weld using a non-consumable tungsten electrode.

Is TIG Welding the Same as Plasma Welding?

No, TIG welding and PTA welding are two different welding processes. In TIG welding, you would form the arc using a tungsten electrode.

TIG welding is the process you can use for workpieces and surfaces that are thin and brittle.

In plasma welding, you would place the electrode in the torch and the arc is gas-infused. This ionizes the gas, forming the electrical arc.

Plasma welding is a process that is better known to cut materials and surfaces.

Can You Use TIG Welding Machines as a Plasma Cutter?

Yes, you actually can.

TIG welding machines have features that you can use to cut metal or steel. However, it might not be as good as a plasma cutter.

Can PTA Welding be Done Using Tungsten Carbide?

Yes, in fact, it’s the usual type of carbide used in the PTA welding process.

Tungsten has tough and resistant properties. So, they are the perfect material to help improve the durability of your machines.

What are the Best Welding Brands?

There are dozens of welding brands in the world – but what are the best ones?

The best welding brands that you can actually take advantage of include:

• Lincoln Electric
• Miller
• Elektriska Sventsnings-Aktiebolaget (ESAB)
• Hobart Welding Products
• AHP
• Everlast
• Fronius

What is PTA Hardfacing?

It’s the process of applying metallurgic deposits on workpieces.

It uses the plasma transferred arc method for deposition and for the coating procedure.

Hardfacing’s goal is to improve the properties and the durability of a part or component.

What is Hardfacing?

Hardfacing is the application of material to a surface or a workpiece through welding.

The most common materials you would need to overlay your parts are:

• Corrosion Resistant
• Wear Resistant
• Abrasion Resistant
• Erosion Resistant

Who Can Help You With PTA Welding?

There are lots of companies out in the market from all around the world.

If you’re looking for the best, China should be your first option. They have the best and the most advanced firms and organizations.

We here at Waldun have the best PTA welding equipment that you can use for your projects.

We’re the best in the region and we serve many clients both locally and abroad.

What are Our PTA Welding Machine Features?

Some of the best features that all our PTA welding equipment have include:

• Breakpoint welding function
• Satisfactory water cooling effect
• Stop and start with just one button
• Simple operations
• CNC-controlled operations
• And many more

What are the features of a PTA welding machine?

• The cladding alloy layer added to the workpiece matrix with high bond strength.
• It has fast cladding speeds with low dilution rates.
• The cladding layer is dense and beautifully formed.
• Plasma welding can directly use on the surface of rusted and oiled metal parts.
• Easy mechanization and automation.
• It has a simple structure, energy-saving, and easy operation.

What are the applications of PTA welding machine?

People are using PTA welding machine in petroleum, chemical, engineering, mining, and other industries.

Sealing welding of various types of valves.

Repair of worn oil drill pipes, bearings, shafts, rollers, wrenches, etc.

What is the classification of PTA welding machine?

PTA welding machine has several types.

(1) Cold-wire plasma welding

Use cold wire plasma welding wire as a filler material, without preheating directly into the welding zone for welding.

(2) Hotwire plasma welding

Hotwire plasma welding uses welding wire resistance of its own preheating and then sent to the plasma area for welding, single wire, or double wire feeding.

(3) Prefabricated plasma welding

Alloy is prefabricated into a specific shape and placed on the surface to be surfaced, which is then plasma melted to form the welding layer.

(4) Powder plasma welding

Powder plasma welding is a welding method in which alloy powder is fed into a plasma arc and melted to create a welding layer. Alloys are mostly made into powder, so powder plasma welding is available in a wide range of materials and is not limited by the ductility of materials like wire.

What is powder PTA welding?

The alloy powder commonly used in powder plasma arc welding is mainly self-fusing alloy powder and composite powder.

Self-fusing alloy powder

Self-fusing alloy powders include nickel-based, cobalt-based, iron-based, copper-based, etc. The iron-based alloy powders are widely used because of the vast raw materials, low price, and good performance.

The iron-based alloy powder is widely used because of the complete raw materials, low price, and good performance.

However, nickel and cobalt are scarce metals with high costs and are generally only used for welding with unique surface properties.

(1) Nickel-based self-fusing alloy powders are divided into nickel boron silicon series and nickel-chrome boron silicon series.

(2) Cobalt-based self-melting alloy powder: B and Si elements are added to the cobalt-chromium-tungsten alloy to form. The cobalt-based self-fusing alloy has excellent high-temperature performance, good hot strength, corrosion resistance, and thermal fatigue resistance. It is more suitable for a high temperature of 600 ℃ ~ 700 ℃ work of oxidation resistance, corrosion resistance, wear-resistant surface coating. Such as high-pressure valve sealing surface welding.

(3)Iron-based self-fusing alloy powder can be divided into two types: austenitic stainless steel type self-fusing alloy and high chromium cast iron type self-fusing alloy.

(4) Copper-based self-fusing alloy powder: copper-based alloy scratch resistance, good plasticity, easy to process. Mainly tin-phosphor bronze powder and add nickel white copper powder.

Composite alloy powder

Composite powders are composed of two or more solid phases with different properties.

The composite powder structure can generally be divided into coated, non-coated, and sintered, and other different categories of powder.

What is PTA powder welding?

PTA powder welding, using the high temperature generated by the plasma arc, the alloy powder, and the substrate’s surface, will be rapidly heated and melted, mixed, diffused, and solidified together. The plasma beam leaves and cools itself to form a high-performance alloy layer. It strengthens and hardens the surface of your parts.

Plasma overlay welding VS Plasma spraying

In principle, the plasma arc is used to generate back to the heat source will be melted powder attached to the workpiece’s surface after the process.

Plasma arc welding consumables and the workpiece bonding strength is better. The metallurgical bonding, the welding layer thickness is thicker.

Plasma arc spraying is suitable for a thin layer, extensive area welding; the arc column is long and can be far from the workpiece welding.

Plasma welding VS laser welding

Plasma is arc welding, the laser is photothermal welding, and plasma is generally more efficient than laser. But extreme field lasers are more suitable.

Laser welding is the process of adding a cladding material to the surface of a substrate, using a high energy density laser beam to melt and condense it together with a thin layer. To form an additional cladding layer on the substrate’s surface, which is a metallurgical combination with the material.

What is the difference between two layers and one layer of the PTA welding machine?

Welding one layer is better in terms of strength.

If the dilution rate in terms of welding two layers better.

Another defect with the base material is what the material is related to the base material’s general hardness is less welding defects.

The thicker the cladding layer, the greater the probability of defects.

Plasma cladding VS Plasma welding VS Plasma spraying

Although they are all plasma welds, cladding, overlays, and blasting are not one process.

Plasma cladding is when alloy powder is used as filler metal, which is heated and melted together with the substrate surface to form an alloy layer.

Plasma welding is applied to repair thicker base materials, such as coal mills, cement mills, and rolls.

Plasma welding is used to repair components with thin base material or suitable for weldings, such as high-pressure boiler tube wall spraying and fan blade spraying.

What gases are used for PTA powder welding?

PTA powder welding is not recommended to use a mixture of gas. It is recommended to use argon gas. It is better to use mixed gas for welding only.

What is the reason that the hardness of plasma powder welding does not meet the standard?

First: different grades of alloy powder (welding consumables) have a corresponding hardness; you can see if the alloy powder problems.

Second, if a specific grade of powder hardness of HRC50, but the hardness after welding is not 50 degrees, it is possible to surface the thickness of too thin.

Plasma Hardfacing Machines and Equipment

There are a lot of plasma and PTA hardfacing equipment and machines you can use.

You can use singular machines, CNC systems, as well as PTA mechanisms and equipment.

The best machines and equipment you can get will depend on your requirement. If you prefer thermal spraying, then you need to purchase machinery that has this capability.

If you, on the other hand, prefer welding, you’d want a welding machine that can perform the hardfacing you need.

Plasma Hardfacing Machines and Equipment Price

The rates and prices of heavy-duty machines like this aren’t stagnant.

You can’t just find them online, you’d have to ask your supplier or your manufacturer for it.

But, you can get plasma hardfacing machines for prices that range from $8,000 to $20,000.

Where Can You Get the Best Plasma Hardfacing Machines and Equipment?

Out of all manufacturers globally, China still has the best and the most renowned companies.

Here in China, Waldun is known as the best and the most trusted plasma hardfacing expert.

We can help you perform the plasma hardfacing you need, as well as provide the equipment for it. You can also ask us to specify a certain machine, following what you need!

Why Choose Waldun?  

For many years, Waldun has dominated the market in providing plasma hardfacing machines and equipment.

We’re ISO 9001 and ISO 14001 certified, guaranteeing you safe and quality products and services.

All our plasma and PTA hardfacing machines and equipment are checked and assessed before distribution. You’ll never have any problems with it!

Contact us now and get the plasma hardfacing equipment you need for a reasonable and a competitive rate!