Pulse TIG welding is an advanced variation of the traditional GTAW process that offers unparalleled heat input control and weld aesthetics. It’s been around for a while in the welding industry, but more welders are embracing this technique to enhance their welding results and efficiency.
Read on to discover what pulse TIG welding is, how it operates, and whether it’s a game-changer in the welding world or just another passing trend.
What Is Pulse TIG Welding?
Pulse TIG welding (GTAW-P) is a sophisticated transfer type of TIG welding where the output current alternates between a high and low value for each pulse.
As a result, the arc switches between hot and “warm” phases, making heat input control remarkably precise.
The high current provides penetration and melts the filler rod into the weld pool. But the low current makes all the difference by preventing burn-through and distortion.
What Is Pulse TIG Used For?
You can use pulse TIG welding for most TIG welding tasks. GTAW-P is renowned for producing superior welds compared to standard DCEN or DCEP TIG welding.
However, pulse TIG welding excels at welding thin stock and exotic materials like titanium and inconel. Aerospace industries use GTAW-P to fabricate components made from exotic alloys. Super-alloys used in jet engines can suffer severe loss of mechanical properties if overheated. So, pulsed TIG is the optimal way to join these sensitive materials, thanks to its low heat input. Some high-tech sectors mandate TIG welding instead of MIG for critical parts. TIG doesn’t introduce as much heat as MIG. So, you won’t induce heat damage and compromise the grain structure of high-performance alloys. You can weld with many standard TIG welders. But pulsed TIG makes it easier to avoid overheating the metal or bringing it to a critical temperature. Consider the pulsed TIG welding process if you’re in aerospace, medical device manufacturing, or high-end fabrication. The GTAW-P is also used extensively for welding titanium in all industries with an almost jewelry-like joint quality.
Main Advantages Of Pulse TIG Welding
The main advantages of using pulse TIG welding include:
Spatter-free welds – TIG welding is already spatter-free, but pulsing ensures even the most difficult-to-weld metals stay clean.
Lowered heat input – Welding thin gauge titanium and super-alloys is far easier because each pulse’s low (background) current helps prevent burn-through, warping, and loss of mechanical properties in heat-sensitive materials like precipitation-hardened nickel alloys.
Achieves near-perfect weld aesthetics – You can “stack dimes” and create jewelry-like finish quality using double-pulsed TIG welding, sometimes called pulse-on-pulse. As a result, you can take on jobs where visual weld appearance is paramount, like welding aerospace components, medical implants, and high-end architectural details.
Higher penetration control – Improves welding precision when joining thin sections (i.e., running hot passes on thin-walled tubing).
Healthier shop environment – TIG is already the cleanest welding process, but pulsing further reduces any potential fumes. CDC and NIOSH suggest that lower heat input reduces the welding fume generation, which may contribute to lowered chances of lung cancer among welders.
Allows out-of-position welding – Unlike standard DCEN TIG, the pulsed TIG can keep the weld puddle sluggish enough for overhead welding. You can use this to your advantage in aerospace, pipefitting, construction, and similar jobs where you need to join metal above you.
Tight weld pool control – The improved sluggishness of the weld puddle can help you bridge root gaps, making pulsed TIG ideal for the root weld pass when welding pipe. The root pass is often made using TIG welding because you can manually control the puddle. But pulsed TIG offers even better control, making the root welding process exceptionally precise.
Improved arc starts – The high amperage of the pulse helps to get the puddle going, but the low background current prevents burn-through on thin stock. Inexperienced welders often burn through the thin materials right at the beginning of the weld. GTAW-P can help you avoid burn-through, even if you don’t move quickly upon starting the arc.
Excellent directional control – Many pulsed TIG machines offer advanced arc shaping features. So, suppose you have hand tremors or little experience with guiding the torch along the joint. In that case, the optimized arc can help alleviate the inefficiencies of movement and improve the weld consistency.
Are There Any Disadvantages To Pulse TIG?
“Non-synergic” GTAW-P welders – “Non-synergic” pulsed TIG welders can be challenging because they lack automatic adjustments. However, “synergic” pulsed TIG machines modify all variables for you when you adjust the amperage, making pulsed TIG far easier to handle.
Pulses lose effectiveness at long distances – GTAW-P may not perform to its maximum ability if you use welding cables longer than 25 ft. or coil them up. Coiling the cables creates additional inductance, which smoothes out the pulses, making them less effective.
Costly investment – The pulsed TIG welders are more expensive than standard, constant current TIG machines. But the advantages are well worth it if you run a high-end fabrication shop. However, if you are a hobbyist considering GTAW-P, it may not be worth your while. Luckily, some budget brands have introduced hobbyist-grade, inexpensive pulsed TIG welders to the market.
Learning curve – While pulsed TIG offers better control, it also requires more skill to master. You need to coordinate your filler rod feeding with the pulse rhythm, which can be tricky for beginners.
May reduce deposition rate – Double-pulsed TIG welding may sometimes slow down your work. It lowers the heat input more than single-pulsed TIG, which can reduce your deposition rate when filling large joints.
What Is Double-Pulse TIG?
Double pulsed TIG welding, also known as pulse-on-pulse (“PoP”), works like standard GTAW-P but adds another pulse layer over the current output. As a result, you’ll have even better control over the heat input and the finished weld aesthetics. Many people get double-pulsed TIG welding wrong, thinking that both pulses alternate the output current between high and low, which is not the case. The two pulses of the double-pulsed TIG welding are:
Pulse 1 – Your standard GTAW-P with peak and background current
Pulse 2 – Significantly reduces the welding current, effectively letting the weld pool cool without extinguishing the arc.
However, many GTAW-P welders allow you to modify the current input during the second pulse.
- Single-pulse GTAW-P prevents burn-through and warping by reducing the mean heat input as it alternates between high and low currents.
- Double-pulsed TIG uses the GTAW-P as its first pulse to stack a single bead. The second pulse significantly reduces the welding current and cools the previous bead.
As a result, the puddle freezes between pulse 1 and pulse 2, creating the jewelry-like “stack of dimes” appearance as you move along the joint. The first pulse lays the bead, while the second lets it cool, creating the mesmerizing ripple weld appearance. The number one advantage of double-pulsed TIG welding is the ability to produce stunning weld aesthetics with less skill required. It may also help you join highly sensitive materials because the second pulse gives the weld and the heat-affected zone (“HAZ”) more time to cool before each consecutive bead. Your high-end projects or jobs you complete at the shop will undoubtedly look better if you use the double-pulsed TIG.
What Is Pulse TIG Welding? Pulse TIG welding (GTAW-P) is an advanced transfer type of TIG welding where the output current switches between a high and low value for each pulse.
As a result, the arc alternates between hot and “warm” phases, making heat input control significantly easier.
The high current provides penetration and melts the filler rod into the weld pool. But the low current makes all the difference by preventing burn-through and warping.
What Is Pulse TIG Used For? You can use pulse TIG welding for most TIG welding jobs. GTAW-P is known to produce better welds compared to standard DCEN or DCEP TIG welding.
However, pulse TIG welding excels at welding thin stock and exotic materials like titanium and inconel.
How Does Pulse TIG Welding Work?
How pulse TIG works Pulsed TIG welding has several stages. The peak current melts off the filler rod’s tip before the background current allows the puddle to cool slightly. But, many variables occur during this transition.
These stages must be appropriately adjusted for your shielding gas, filler rod diameter and type, and the welded material type.
That’s why synergic GTAW-P is the best way to go since any mishap in manual pulsed TIG settings would result in poor results.
Synergic pulsed TIG machines automatically adjust the peak current, background current, pulse frequency, and pulse duration as you change the amperage.
So, you can adjust everything with one knob. However, not all machines are as simple to operate.
How the welding current on pulse TIG works Let’s explain each step of the GTAW-P: Pulse frequency – The number of pulses that occur in one second. It can range from a few pulses per second (“PPS”) to a few hundred PPS.
Peak/Pulse/High current – The highest current output during the pulse peak. It must be high enough to create a stable arc and provide good penetration.
Peak current time – The length of peak current time. Long peak current time may increase penetration and deposition rate. However, too long of a peak current time causes a wide and overly-liquid puddle, making it challenging to control in out-of-position welding.
Background/Low current – The lowest current output during the pulse duration. The higher the current, the deeper the penetration. But, if the current is too high, you will only reap some of the GTAW-P benefits. Background duration – The length of background current time. The longer the background duration, the more the weld pool can chill and become sluggish.
Mean/Average current – Average current input directly affects the average heat input into the material.
Arc control/Trim – Adjust the tungsten tip to the weld pool distance. It allows you to fine-tune the arc for better control.
Pulse balance – Used with double-pulsed TIG to adjust the length of the main pulse within each cycle.
Synergic GTAW-P welders auto-set these settings for you. Some brands also let you manually modify some or all of these settings.
But it’s best to stick to synergic settings until you get more experience with this welding process.
Metals You Can Weld With Pulse TIG
Pulsed TIG is best for joining titanium, inconel, hastelloy, and specialty alloys like super-duplex stainless steels.
While you can pulse TIG weld mild steel, you would only benefit from GTAW-P when welding thin sections.
Pulse TIG Welding Vs. Other Transfer Methods TIG Transfer Modes
The GTAW-P welding process offers many benefits compared to standard TIG methods, so let’s examine each and explain how GTAW-P works differently.
DCEN TIG Vs. Pulse TIG
DCEN (Direct Current Electrode Negative) is the most basic TIG mode used by most welders for non-aluminum metals.
The tungsten electrode is connected to the negative terminal, concentrating heat on the workpiece for good penetration.
However, with thin materials or out-of-position welding, DCEN can provide too much heat, causing burn-through or puddle control issues.
Unlike standard DCEN, pulsed TIG alternates between high and low current, giving you better control over heat input and puddle fluidity.
DCEP TIG Vs. Pulse TIG
DCEP (Direct Current Electrode Positive) is rarely used in TIG welding. It’s primarily for cleaning oxides off aluminum, but it generates excessive heat on the tungsten.
DCEP isn’t suitable for most welding tasks due to poor penetration and rapid tungsten wear.
Pulsed TIG welding is significantly better than DCEP TIG in every way. So there is no reason to opt for DCEP TIG instead of GTAW-P.
AC TIG Vs. Pulse TIG
AC (Alternating Current) TIG is commonly used for welding aluminum and magnesium, alternating between DCEN and DCEP to balance penetration and cleaning action.
It works well for these metals but can be challenging to control the heat input precisely.
The GTAW-P provides controlled heat input during the peak current.
But it lowers the output during the background phase to prevent burn-through on thin material and allow out-of-position welding.
Is It Worth Buying A Pulse TIG Machine?
It is worth buying a pulsed TIG machine, especially if precision welding is your primary source of income. A GTAW-P welder could significantly improve your quality and reputation if you run a specialized shop.
Hobbyists can also benefit from GTAW-P by achieving better-looking welds and avoiding burning thin materials.
If you frequently work with aerospace parts, medical devices, or weld thin exotic alloys, the GTAW-P is worth it.
But if you only weld occasionally, getting costly pulsed TIG equipment may be a waste of money.
However, if you spend significant time working on high-precision DIY projects, GTAW-P may elevate your work quality and appearance.
How Much Does A Pulse TIG Welder Cost?
Pulsed TIG welders usually cost several thousands of dollars. But there are outliers beyond this article’s scope, like the inexpensive TIG-200PI AC/DC TIG Welder and the highly expensive, industrial-grade TIG-400PI AC/DC TIG Welder.
TIG-200PI AC/DC TIG Welder – High-End Pulsed TIG Welder The TIG-200PI is a portable powerhouse with a maximum output of 200A and a 60% duty cycle at 200A. It’s designed for professionals with an emphasis on versatility.
So, if you turn on the pulsed TIG mode, it auto-sets everything for you. You must select the welded material, joint thickness, and tungsten size.
It also allows you to fine-tune the settings manually so that you can adjust the parameters for nuanced specifics of any job. This unit includes both single-pulse and double-pulse TIG welding.
Wrapping It Up
The GTAW-P welding process is not new, but it’s gaining traction as more brands implement innovative technologies to make this process as “synergic” as possible.
The pulsed TIG was too challenging to use when it was introduced in the 1960s. But, nowadays, it’s almost “plug and play,” especially with professional welders like the TIG-200PI AC/DC TIG Welder.
We still haven’t seen wide adoption of the pulsed TIG welding process except in the industries that mandate it, like aerospace and medical device manufacturing. However, more and more specialized shops are introducing the GTAW-P because it improves precision and enhances weld aesthetics.
Thankfully, the hobbyist and DIY space is also getting some exposure to the pulsed TIG process.
