MIG welding has several metal transfer modes, and each mode serves different welding needs. It works well for both simple and demanding welding jobs across industries.
In this guide, we’ll explain how spray transfer welding works and how to use it effectively. How it operates and which equipment is required for its setup.
What is Spray Transfer Welding?
Spray transfer welding is a sub-type of MIG welding in which molten metal from the welding wire or electrodes continuously transfers to the weld pool.
The droplets are smaller than the wire diameter and are pushed through the arc by electromagnetic force.
Technically, spray transfer welding operates at high current and high voltage, using shielding gases such as argon and argon mixtures to keep the arc stable.
This results in deep penetration, a high deposition rate, a clean bead, and very low spatter.
Core Features
- It offers non-stop transfer of molten metal.
- It features deep penetration, high deposition rate, and great fusion.
- It features high arc stability and low spattering.
- It is highly compatible with welding thicker materials.
- It works at high current and high voltage values.
- It features neat, clean, strong, and reliable welds.
Types
- Conventional Spray Transfer:This type of spray transfer welding features continuous transfer of molten metal to the weld pool. It also uses a mixture of argon and other elements, resulting in a clean, durable, and long-lasting weld.
- Pulsed Spray Transfer: The PST is an advanced spray transfer welding process that features two current modes: high and low. It allows control over heat, spattering, and other issues, especially with thin and out-of-position materials.
Spray vs Globular vs Short-Circuit: What’s the Difference?
MIG welding uses several metal transfer modes.
Understanding how spray transfer differs from short-circuit and globular modes helps welders choose the right settings for each job.
1. Short-Circuit Transfer
Best for: Thin metal, sheet metal, automotive bodywork
Amperage: ~50–150 A
Gas: 75/25 Ar-CO₂ or 100% CO₂
How it works:
The wire touches the base metal and creates a short circuit 20–200 times per second. The tip melts and snaps into the weld pool.
Characteristics:
- Low heat input
- Suitable for thin materials
- Works in all positions
- Some spatter
- Easy to control
Best use:
Sheet metal, car panels, thin steel under 3 mm.
2. Globular Transfer
Best for: Medium-thickness steel
Amperage: ~150–250 A
Gas: CO₂-rich mixes
How it works:
Large droplets form at the wire tip and fall into the weld pool by gravity.
Characteristics:
- Medium heat input
- Less stable arc
- Large droplets → more spatter
- Mostly flat position
- Economical (can use CO₂)
Best use:
General fabrication on medium-thick steel.
3. Spray Transfer
Best for: Thick materials and high-quality welds
Amperage: ~200–450 A
Gas: 90–98% Argon
How it works:
Tiny molten droplets are projected across the arc hundreds of times per second.
Characteristics:
- High heat input
- Deep penetration
- Very stable arc
- Almost zero spatter
- Flat and horizontal positions only
Best use:
Structural steel, industrial machinery, aerospace components, heavy fabrication.
Comparison Table
| Feature | Short-Circuit | Globular | Spray Transfer |
| Heat Input | Low | Medium | High |
| Spatter | Low-Medium | High | Very Low |
| Penetration | Shallow-Medium | Medium | Deep |
| Best Thickness | Thin | Medium | Thick |
| Positions | All | Mostly flat | Flat & horizontal |
| Gas | CO₂ mixes | CO₂ mixes | Argon-rich |
| Arc Stability | Good | Unstable | Very stable |
| Deposition Rate | Low | Medium | High |
| Skill | Easy | Medium | Medium-High |
How Spray Transfer Welding Works?
Spray transfer welding works through the following steps:
1: Arc Formation
The arc formation between the welding wire and base metal is the first step in the working mechanism of spray transfer welding. It includes setting high current and high voltage to generate heat.
This heat melts the electrode tip and a small portion of the base metal, forming the weld pool. The shielding gas here helps prevent contamination.
2: Droplet Formation
Once the electrode tip melts, it forms molten droplets, which are then separated by electromagnetic forces and heat.
Overall, the droplets are smaller than the electrode diameter and occur at a rate of hundreds of droplets per second.
Keep in mind the parameter adjustment, as the quality of proper droplets depends on the current, voltage, and shielding.
3: Droplet Acceleration
In this step of droplet acceleration, the droplets are propelled through the arc and sprayed at the weld pool. Electromagnetic forces accelerate drops, resulting in straight, smooth, spatter-free motion.
Just have an eye on the arc length, voltage, and wire feed speed to ensure smooth acceleration and stable operations.
4: Continuous Metal Transfer
As we already know, spray transfer welding is characterized by a continuous droplet spray. Overall, the droplet spray transfer happens hundreds of times per second.
On the other hand, this continuous stream results in a high deposition rate, deep penetration, and a desired bead. Other subtypes of MIG transfer modes lack this feature.
5: Weld Pool Formation
Here, in the final phase of the working mechanism of spray transfer welding. The droplets fuse with the base metal to form a weld pool, and as the welder moves away from the torch gun, the molten pool begins to solidify and cool.
The final result is a strong, reliable, durable, and clean weld or bond between the materials.
What Equipment Is Needed for Spray Transfer Welding?
1: Power Source
Like other MIG welding subtypes, spray transfer welding also uses a constant-voltage (CV) power source. According to the recommended parameters, the current must be around 200-450 A.
It usually uses the Direct Current Electrode Positive (DCEP) method to ensure deep penetration and stable arc performance.
2: Wire Feeder
The wire feeder supplies the electrode or welding wire to the weld pool at a controlled wire feed rate. It manages instability and maintains arc stability.
In the current times, digital controls are also introduced to monitor the real-time values and make the adjustments accordingly.
3: Welding Torch
As we know, the welding gun delivers current, shielding gas, and filler wire to the welding area.
Similarly, it includes a contact tip, a gas nozzle, and a wire guide to perform this delivery operation.
To handle high heat and current, welders prefer the water-cooled MIG gun at an appropriate angle for effective results.
4: Shielding Gas
Shielding gas in welding operations prevents contamination from air, oxygen, nitrogen, and hydrogen.
As recommended, the spray transfer welding must use a shielding gas composition of 95-98% Argon + 2-5% CO2, or pure Argon.
Keep in mind that experts don’t recommend using pure CO₂.
5: Filler Wire
According to the expert’s opinion, the following wire materials are suitable for selection, as they will serve as both electrodes and filler materials.
It includes ER70S-6 for carbon steel, ER308L / ER316L for stainless steel, and ER4043 / ER5356 for aluminum. Make sure to choose neat, clean, and rust-free wire.
Where Is Spray Transfer Welding Used?
1: Automotive Industry
Spray transfer welding is widely used in the automotive industry for multiple applications, including car frames, chassis, and automotive panels.
This type of welding is prioritized in this industry due to efficient, clean, and long-lasting weld quality.
2: Industrial Machinery
Spray transfer welding is used in the manufacturing of heavy industrial machinery, such as cranes, excavators, bulldozers, and other equipment.
This type of welding is best suited to thicker materials, making it preferred for the manufacturing of industrial machinery.
3: Aerospace and Defense
Its use in aerospace and defense components highlights its reliability for critical, high-strength applications.
Yes, this type of welding is used to weld steel, nickel-based alloys, or other high-performance metals.
4: Pipeline and Heavy Piping
The spray transfer welding also holds a strong position in the pipeline and piping industry. It is used to weld the pipes carrying water, gas, oil, and other materials.
They require a strong base, no leakage, and long-lasting effects. The spray transfer welding does it well.
5: Heavy Steel Fabrication
In heavy steel fabrication, spray transfer welding is used to bond large components, such as bridges, buildings, and shipbuilding structures, as well as other steel components.
All of these materials are thicker, and spray transfer holds them well.
How Do You Adjust the Parameters?
- Voltage: It controls arc length and stability. The ideal voltage range is 24-36 V.
- Amperage: It manages the heat input level. The ideal amperage range is 200-450 A.
- Shielding Gas: It mitigates oxidation effects. The ideal shielding gas ratio is 95-98% Argon + 2-5% CO2, or pure Argon.
- Electrode Wire: It should be compatible with the base weld, like ER70S-6. The ideal range for mild steel is 0.8-1.2 mm.
- Wire Feed Speed: It controls the current rate; a higher speed means a higher current. The ideal range is 8–18 m/min.
- Stick-Out: The length of wire from the contact tip to the workpiece. The ideal length is 12–25 mm (½–1 inch).
What Are the Pros and Cons?
Advantages
- Superior Weld Quality
- High Deposition Rate
- Deep Penetration
- Stable Arc
- Suitable for Thicker Materials
Disadvantages
- Supports Flat or Horizontal Position Welds Only
- High Amount of Heat Production
- Somehow Expensive Setup
Conclusion
Spray transfer welding is one of the most effective methods for producing high-quality welds on thick materials. It features deep penetration, minimal spattering, great fusion, and a stable arc.
Most industries, such as automotive, manufacturing, construction, and aerospace, rely on spray transfer welding for durable results. It is one of the most stable and efficient metal transfer modes in the GMAW process.
Again, be sure and confident about the parameter adjustment if you really want the remarkable results. Moreover, be cautious about the safety measures before starting the welding work.
If you’re searching for a reputable welding supply company offering durable and affordable equipment, YESWELDER is a top choice. Their product range covers MIG welders, TIG welders, Stick Welder, welding helmets, and accessories, making it easy to get all your welding tools from one trusted source.
FAQs about spray transfer welding
Spray transfer needs high voltage and high current.
This means you usually need a more powerful welder.
It also creates more heat.Thin metal can warp, burn through, or lose its shape more easily.
Short-circuit transfer occurs when the MIG wire touches the metal and creates repeated short circuits.
It uses low heat, works on thin materials, and is suitable for all positions—but produces more spatter.
Spray transfer uses high current and argon-rich gas to project tiny droplets across the arc in a smooth stream.
It has deep penetration, very low spatter, and high deposition, but only works on thicker materials and in flat/horizontal positions.
With a 90/10 gas mix and 0.035 ER70-S6 wire, spray transfer usually starts at 27–28 volts.
This setting normally produces about 190–230 amps.
Wire feed speed for stable spray is often 340–420 IPM.
For 0.045 metal-cored wire, spray transfer typically runs at 25–27 volts.
A wire feed speed of 300–350 IPM produces roughly 220–240 amps.
Yes, you can.
.035 wire can reach spray transfer if your welder has enough power.
You usually need higher voltage and higher amperage to enter spray mode.
Most machines need around 180–220 amps to spray with .035 wire.
If the welder is too small, the wire will stay in short-circuit mode.
No, it cannot.
Spray transfer is mostly limited to flat and horizontal positions.
The weld pool is very hot and very fluid.
Gravity makes it hard to control in vertical or overhead positions.
For those positions, short-circuit or pulsed MIG works much better.
