13 Most Common Pipe Welding Mistakes and Best Preventions (Part 2)

A tight grasp of most common mistakes in pipe welding process and how to avoid them will benefit tremendously your process of new welder training, raising quality and productivity and improving safety.

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13 Most Common Pipe Welding Mistakes and Best Preventions (Part 1)

7. Think welding power sources cause porosity

Some welders blame welding power sources for porosity in welding. Indeed, they are not the culprit of this problem. If welders track back their steps from the point that porosity began, they will often find that this problem began when a wire spool was changed, a new gas cylinder was used (loose connections, wrong gas used), when someone failed to prepare properly the materials (oxides appears in the weld), or if the material suffered contamination from somewhere else along the line. Most often, the problem results from an interruption, or trouble with the gas flow. Looking back their steps, welders will often realize the variable causing the porosity.

 8. Use wrong type or size of drive roll

While flux cored wires should be employed with the knurled drive roll, a standard V drive roll should be used for solid wires. Critically, welders remember to change those out when changing types of wires in their machines. Welders that wrongly use the standard V drive roll with the flux cored wire will often notice this wire slipping, crank down on the tension of drive roll to hold it in place, thereby crushing the cored wire. When incorrectly using the knurled drive roll with solid wire, welders will notice the roll chip off the outer coating on the wire, and that induce plugging up the liner. Then welders tend to crank on the tension; that just worsens the problems.

If welders find themselves having to crank on the wire tension, it indicates something else wrong with the process – incorrect drive roll, incorrect drive roll size, clogging in the liner. Work the process, ensure using the right drive rolls, and they will likely find the cause of the problem.

 9. Add cleaning solvent or lubricant to the dust pad

Some shops add the dust pad (i.e. a small piece of fabric) just before the drive roll system to get rid of any final contaminants from the wire. This is fine on its own, but some shops have been seen to add cleaning solvent or lubricant to the pad to further enhance feeding or clean the wire. That turns out to have the opposite effect – those oil, indeed, contaminate the wire, and can induce weld defects. For added protection or as an alternative, welders can also add a spool cover to save the spool of wire from the airborne contaminants.

10. Use wrong nozzle size

There require different types and sizes of nozzles for different Mig processes. For example, a tapered nozzle is recommended for the regulated metal deposition process. Still, that same tapered nozzle can’t address the gas flow requirements of pulsed Mig process, and will induce inappropriate gas coverage of the weld. Seize which nozzles is suited for each process/ variable, and use accordingly.

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11. Fail to select a Mig gun rated for handling peak amperage when pulsing, and mixed gases as well

When shops specify a Mig gun for the pipe applications, they will often choose a Mig gun by the average amperage of their application. They may purchase a Mig gun of 250 amperage, and have 250 amps as the average amperage. But they are applying substantially higher amperage to that gun during the peak of pulsing cycle. Those guns aren’t designed for that peak amperage and then can burn out more quickly. 

Likewise, Mig guns are often rated for use with 100% CO2. That is fine for the applications welding with 100% CO2 though, that available amperage on that gun reduces once the mixed gas common in pipe welding applications is applied.

Many shops find for low amperage guns as they are lighter and less costly, but that isn’t good in the long run. They should select the Mig gun rated for dealing with peak amperage when pulsing, and mixed gases as well.

12. Jump into mechanized/ automated processes without seizing why

One common mistake is the desire to apply mechanized or highly automated robotic process without doing the homework. The automated welding processes can just as effective as upstream and downstream processes in a shop. The automated cell isn’t helpful when sitting idle because upstream processes are still slow, or when creating new bottlenecks downstream.

There are 2 important things that a shop must do first – Seize the issue they are trying to handle through automation, and them make everything else in the operation simple to make sure of the appropriate workflow as well as optimal efficiency at each station. 

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13. Rely on smaller, less expensive machines

There are shops that use 250-amp shop welders and believe they will give the needed power and performance to carry out any pipe welding applications. They may be right, in some cases.

Still, those smaller, less costly machines would feature lower duty cycles, fewer capabilities. If your shop takes pipe fabrication seriously, and desires to maintain high levels of productivity, operating at the higher duty cycles will guarantee consistent use. It’s far from similar between 250 amperage at 20% duty cycles (2 mins on out of a 10-min cycle) and 250 amperage at 100% duty cycle (10 mins of continuous welding in a 10-min cycle).

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13 Most Common Pipe Welding Mistakes and Best Preventions (Part 1)

A tight grasp of most common mistakes in pipe welding process and how to avoid them will benefit tremendously your process of new welder training, raising quality and productivity and improving safety.

See also:
13 Most Common Pipe Welding Mistakes and Best Preventions (Part 2)

Whether it is about welding pipes for oil and gas industries or food and beverage, there are common problems that those in pipe welding positions overseas or locally should know about and find best ways to avoid. Those problems include everything from selecting a Mig gun with too low amperage to inappropriate drive rolls and shielding gas.  Because companies have been earnestly training new welders, working with new materials, raising quality and productivity, and improving safety, it is significant to center on some of those issues in pipe welding process that may affect those efforts. Given below are 13 most common mistakes made in pipe welding and how to avoid them.

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Most common pipe welding mistakes with preventions

1. Forget to grind the joint after plasma or oxy-fuel cutting

Both plasma and oxy-fuel cutting processes add an oxide layer to the cut edge. This layer must be got rid of before welding because the oxide, commonly, has higher melting point than the base metal. The arc being hot enough to melt the oxide is synonym to that it’s too hot for base metal and can induce burn-through. Also, the oxides can remain in the weld, and lead to porosity, lack of fusion, inclusion and other defects of welding. Importantly, welders remember to grind the joint down to parent material before welding, and grind inside out diameters of the pipe to get rid of those oxides as well as other potential contaminants.

2. Make poor cut that induces poor fit-up and necessary gaps

When welders work on materials more subject to distortion and influences of higher heat input – for example, aluminum, stainless steel, a poor cut can be conductive to poor fit-up and produce unnecessary gaps. Then to fill it, welders compensate by placing more filler metal (hence, heat) into the joint. That added heat can induce distortion, and with such corrosion resistant pipes as stainless steel, can worsen the corrosion-resistance of the base metal. Also, it can result in incomplete or excessive penetration. Not all, poor preparation induces longer weld cycle times, potential repairs and higher consumable costs.

Currently, shops employing band saws or chop saws to cut pipe should consider purchasing specialized orbital pipe cutting equipment to ensure cuts within thousandths of an inch of specified parameters. That precision would help guarantee best fit-up and minimize the amount of filler and heat into the joint.

3. Forget to cut out and feather tacks

Tacking is crucial to fit-up, and welders are recommended to cut out and feather tacks to ensure consistency of the final weld. Specially, in shops that a fitter gears up for the pipe and somebody else welds it, it is important that the welder knows what is in the weld. The tack left in the joint would be consumed by the weld. If there is a tack defect, or if the fitter employed the incorrect filler metal to tack the joint, there may induce defects in the weld. To avoid this potential problem, cut out and feather the tacks.

4. Prepare a joint for Mig welding processes in the same way as for stick welding

Welding training is a top priority in many shops. Not few welders apply past experiences to the new job. Those experiences can be dealt with adequate training though, one common mistake is that welders with stick experience don’t understand how to appropriately prepare a joint for the wire processes in pipe welding applications. Often, those trained in stick and Tig welding prepare the joint with the heavy landing area and desire to keep the gap narrowest as possible. Because shops now turn to such easier and more productive Mig processes as Regulated Metal Deposition, they prefer that welders take down the landing area to an edge of knife and space the joint at about 1/8 inch. This area is wider than that that those trained in stick and Tig processes use, and can induce various problems – for instance, incomplete penetration, too much heat into the weld edges, not enough reinforcement on inside of the pipe. Then shops should train their welders about particulars of each application and ensure they understand weld preparation and operational techniques before they come to work.

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5. Mistakenly believe that more shielding gas is always better

A misconception among some welders is that more shielding gas is better. They crank gas wide open, and mistake that they are giving more protection to the weld. That technique results in lots of problems like wasted shielding gas in terms of cost and resources, increased agitation of weld puddle, convection effect sucking oxygen into the weld and inducing to porosity. Each station should be equipped with a flow meter, and each welder should seize how to set and follow the recommended flow rates.

6. Count on mixing with the flow regulator

There are shops that build a separate tank of helium and a separate tank of argon for the stainless steel application that needs 75/25% of argon/ helium. Then they count on the flow regulator to bleed in the right amount of shielding gas. In fact, with this method, you won’t know what you get in a mix. Buying mixed gas from trusted sources, or buying an appropriate mixer will ensure you exactly know what you are shielding your weld with and you are following proper weld qualifications/ procedures.

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10 Powerful Ways to Avoid Lack of Fusion in Welding

Make sure your welders know those causes and ways of preventing lack of fusion in welding…

Lack of fusion in welding occurs when there isn’t fusion between weld metal and the surfaces of base plate. Most commonly, this problem is the consequence of poor welding technique. Using very wide weld joint can also be conductive to lack of fusion. Heat input, position, electrode and work angle are also very important for obtaining best fusion results. Along with causes of lack of fusion, practicable ways to prevent the defects of welding are specified below. You can refer and ensure your welders are equipped with enough skills to stay away from this problem.

1. Good welding techniques

Too large weld puddle (too slow travel speed) would end up with lack of fusion. In this case, keep the arc on the leading edge of puddle. By so doing, the weld puddle won’t be too large and cushion the arc.

2. Making the weld joint narrower

Lack of fusion can result from using very wide weld joint. If you direct the arc down the joint center, the molten weld metal won’t melt the side walls of base plate but just flow and cast against them. The arc heat must be used to melt base plate. To do so, make the joint narrower or direct the arc toward the base plate’s side wall. When you multiple pass weld thick material, use a split bead technique whenever possible after root passes. Avoid large weld beads that bridge the whole gaps.

3. High heat input

Less heat input would be conductive to poor fusion. Heat supply is related to welding current, voltage and travel speed. It is directly related to voltage and current, and inversely associated with travel speed. Low current/ voltage settings lead to insufficient heat supply. On the other hand, the same problem would result from faster travel. Then adjust maximum allowable current, and blend the weld metal with moderate space.

4. Oxide/ Scale removal

Weld joints can be prone to atmospheric contamination. Oxide film or any unwanted particle may hamper the fusion process and do harm to weld properties. That’s why it’s recommended to get rid of any strange overlay on the joint. Clean the joint before welding will help prevent lack of fusion.

5. Correct angles

Electrode and work angles are important for attaining best fusion results. Ensure correct electrode angle with moderate pace, as wrong electrode handling would make liquid weld interrupt the arc activity.

6. Bead orientation

Slot and fissure between weld beads can appear if you incorrectly position them along the joint wall. Slot developed may induce slag inclusions and thereby lack of fusion. Your welder must be trained enough to correctly place the beads and ensure complete blend of weld along the side wall.

7. Vertical uphill position

Partial fusion may eventuate due to root pass with vertical downhill position creating disruption in the process. For this problem prevention, vertical uphill is preferred.

8. Edge preparation

Good preparation of edge would contribute to perfect welding. Variation in root attributes results from joint pieces unaligned in the same plane. Also, in case of too large root face, the weld metal won’t completely fuse at root. Meanwhile, small root opening can influence aspects of fusion, resulting in un-fused output. Then it’s recommended to confirm the right root opening before starting the welding procedure.

9. Proper welding parameters

The penetration depth decreases as you raise the voltage but change no other parameters. Choose welding parameters (high level of current, short arc length, not too high welding speed) for promoting penetration into joint side wall without causing flooding.

10. Right voltage and inductance

For short circuiting mode in the Mig/ Mag process, inductance might surpass the given level, inducing serious fusion problems. Indeed, the magnetic field generated by immoderate inductance hinders the welding current from rising. In this case, the wire tip metal isn’t heated enough and doesn’t fuse with the parent metal. There requires proper adjustment of voltage and inductance settings to avert spattering and lack of fusion because too low inductance would lead to serious spatter. Appreciably, employ modern equipment with advanced power source that offers regulated voltage and inductance values.

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6 Useful Tips for Preventing Flux Core Welding Problems (Part 2)

With some tips and practice, you can avoid flux core welding problems and improve your FCAW welds.

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4. How to avoid weld undercutting and lack of fusion

Same as other weld defects, lack of fusion and undercutting can lower your welds quality and prevent them from going far in reduction of downtime and rework costs.

How to prevent undercutting

Undercutting is the aftermath of a groove melting in the base metal next to the weld toe but not being filled by weld metal. It weakens the toe of weld and often induces cracking. Applying appropriate welding voltage and current helps prevent this problem (don’t forget to conform to your welding parameters). Maintain the travel speed that enables the weld metal to completely fill the base metal’s melt-out areas. If you are applying the weaving technique, pause at the weld bead’s each side.

How to prevent lack of fusion

To avoid lack of fusion that eventuates due to the weld metal failing to completely fuse with the base metal (or the preceding weld bead in multi passes), maintain right work angle and heat input. Get the right angle by putting the stringer bead in its appropriate location at the joint, widening the groove or adjusting the work angle to approach the bottom during welding as necessary. Keep the arc on the welding puddle’s trailing edge, and maintain the gun angle drag of 15 - 45°. If you are applying a weaving technique, hold the arc on groove sidewalls for a moment during your welding. Raise your voltage range or/ and adjust wire-feed speed as needed to get complete fusion. In case you feel the wire is going ahead of the work puddle, such simple adjustments as applying higher welding current or raising travel speed can avoid problems.

Finally, make sure you clean the surface of base metal before welding to get rid of contaminants to avert lack of fusion.

5. How to prevent lack of penetration or excessive penetration

How to prevent incomplete and excessive penetration

Maintain proper heat input when welding is critical to preventing such problems as excessive penetration. The excessive penetration happens due to the weld metal melting through base metal and hanging underneath the weld. Most often, it is the consequence of too much heat. If you encounter the problem, choose a lower voltage range, decrease the wire-feed speed and raise the travel speed.

By contrast, choosing a higher voltage range, higher wire-feed speed or/ and reducing the travel speed can avert such problems as lack of penetration (i.e. shallow fusion between weld metal and base metal). Also, prepare the joint for permitting access to the groove bottom whilst maintaining appropriate extension of welding wire and arc characteristics. 

6. How to get qualified FCAW welds

Self-shielded FCAW is a trusted process for various construction applications though, getting qualified welds with it is not the luck of the draw. It results from good welding techniques, appropriate choice of parameters, and your ability to avert problems or quickly define and rectify them. Remember, preparing yourself with some essential information will enable you to avoid most common problems related to FCAW welding without sacrificing quality or time.

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6 Useful Tips for Preventing Flux Core Welding Problems (Part 1)

With some tips and practice, you can avoid flux core welding problems and improve your FCAW welds.

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When it comes to structural steel erection, bridge construction, heavy equipment repair, and other same applications, FCAW (Self-Shielded Flux Cored Arc Welding) has been, for many years, a feasible welding process. Unsurprisingly, because it provides high deposition rates, fantastic mechanical and chemical properties and weldability needed for those jobs. Yet, there exist some challenges related to this process. With some tips and practice, you can avert the problems and create qualified welds you need.

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1. How to avoid wire feed welding problems

Common problems at workshops are wire feed malfunctions and stoppages caused by a significant number of downtime. Bird-nesting and burn-back are 2 most notorious types of wire feed welding problems. Those types tend to prematurely extinguish the arc, inducing weld defects. 

Burn-back happens when the wire melts into the ball at the end of contact tip. Most often, it’s the consequence of too slow speed of wire feed or/ and the welding gun held too close to the work-piece. For this problem prevention, make sure you use the proper feed speed and keep a distance of no more than 1 ¼ inch from the contact tip to the work.

To avoid bird-nesting  - a wire tangle halting the wire from being fed - when FCAW welding, use knurled U or V-groove drive rolls in the wire feeder. Comparatively with GMAW solid welding wire that employs smooth V-groove drive roll, the FCAW wire is far softer because of tube-shaped design. It can compress the wire if you use wrong drive roll.  

Also, setting the right drive roll tension can stave off the wire flattening and being tangled. In order to set the correct tension, start with releasing tension on drive rolls. Raise the tension whilst feeding the wire into the palm of welding glove and keep raising the tension one half turn to pass wire slippage.

Bird-nesting also results from blockages in the liner, wrong liner used, or inappropriately trimmed liners. Quickly replace the liner if you find out a blockage when routinely inspecting your welding cables and gun. Also, always trim your liner (employing the correct tools) in line with the manufacturer’s recommendations. Make sure that there isn’t any sharp edges or burrs on the liner, and always apply the proper size liner for the diameter of welding wire.

2. How to prevent worm tracking and porosity

As typical weld discontinuities, worm tracking and porosity can weaken the weld integrity. 

Porosity occurs when gas is trapped in the weld metal, and can appear along its full length or at any particular point of the weld. For preventing porosity in welding, get rid of any grease, rust, oil, paint, coatings, dirt and moisture from the base metal before you weld. You can also use filler metals with added de-oxidizers to prevent contaminated welds. Still, those products can’t replace appropriate pre-cleaning. After that, maintain a proper electrode stick-out or extension. Generally, the wire shouldn’t extend more than 1 ¼ inch beyond contact tip.

To avert worm tracking (also, marks on the weld bead’s surface as a consequence of gas created by the flux in the wire core), avoid immoderate voltage for the wire feed setting as well as amperage. For the best, follow the recommended parameters by the manufacturer of filler metal for the particular diameter of welding wire. In case worm tracking occurs, decrease your voltage by one half volt’s increments until you remove the problem.

3. How to remove slag inclusions

Slag inclusions eventuate when the slag produced by the molten flux in the wire core gets trapped inside the weld. Whatever causes of this problem, they can be averted with appropriate welding techniques.

First, prevent wrong placement of weld bead, especially when making many passes on the thick metal sections. Be sure to give adequate space in the weld joint for added passes, particularly, on the joints in need of multiple passes.

Second, keep up with correct travel speed and travel angle. From 15 to 450º should be the drag angle in the overhead, horizontal and flat positions. For vertical up position, the angle should be in range of 5 – 150º. In case there are slag inclusions at those angles, raise slightly the drag angle. Keep a steady travel speed. If you make too slow travel speed, slag inclusion due to weld puddle getting ahead of the arc will eventuate.

After that, maintain appropriate welding heat input, because too low heat input can be conductive to slag inclusions. Always apply the parameters recommended by the manufacturer for a certain wire diameter. In case slag inclusions still happen, raise the voltage until this problem stops.

Finally, make sure you thoroughly clean between the weld passes, taking away any slag using a wire brush, chipping hammer or grinding before you begin the next weld pass.

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Porosity in Welding - Causes and Preventions (Part 2)

What are most common causes of porosity in welding and how can be they prevented? You can refer below to find the answers you need.

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Porosity in Welding - Causes and Preventions (Part 1)

6. Excessively long arc length

Weld porosity occurs in case of excessively long arc length (also, high voltage). The shielding magnitude will be reduced, inducing air entrapment if the welding gun is kept away from the joint making longer arc length. Proper arc length is suggested to avert breezes/ draughts.

7. Wrong surface treatments

Weld characteristics can be weakened due to released gases during surface/ painting treatments. Such treatments as galvanizing or zinc coating would create gas and other particles unwelcomed. As a prevention, predict the result of chemical reactions prior to particular surface treatments.

8. Laminated surface

Welding disturbance can also eventuate in case of laminated surface. When welding the laminated work piece, gear up for unlaminated parent metal to ensure the qualified weld procedure.

9. Open surface

Any surface open to the atmospheric air would be prone to contamination. Air introduced from the back side via root opening would be entrapped in the weld puddle. Ensure that your weld joint is safeguarded from such air crevices.

10. Improper welding flux

Welding flux is required to be cautiously treated because of their moisture absorbility. They must be provided in dry conditions. It also should be noted that using low-activity flux induces surface porosity. Then you’re recommended to apply high-activity flux that offers qualified welds without porosity. 

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Porosity in Welding - Causes and Preventions (Part 1)

What are most common causes of porosity in welding and how can they be prevented? You can refer below to find the answers you need.

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Porosity is defined as cavities in a weld as a consequence of gas entrapment. The gas introduction in the weld is associated with certain mistakes that should be eliminated. The in-weld metal porosity is varied by location and shape of occurrence. For example, while some gas cavities are in spherical shape, some, like the worm holes, are in long shape. Then to predict mistakes possibly causing porosity and the related preventions is important before welding. Specified below are details about most common causes of weld porosity along with their solutions.

1. Moist electrodes

As recommended, employ the baked electrodes in the process of stick welding to avoid any moisture content involved in the weld metal. At worst, there may be small cavities created in the weld metal because the steam can be driven out during the welding heat. Porosity occurs when the low hydrogen electrodes or stainless steel electrodes aren’t appropriately kept in the dry condition. Certain moisture is needed within a limit in low hydrogen electrodes though, in some case, the weld metal will be subjected to porosity if moisture surpass the limit. Follow those steps for prevention:

• Parent metal is required to be preheated for moisture removal.

• The electrodes must be kept in the dry condition.

• Before use, apply last backing.

• It is a must that electrodes are not oven baked prior to use, as there requires a humble amount of moisture for enhanced performance and weldability of electrode.

2. Polluted surface

Parent electrodes or metals may be prone to contamination in the atmosphere. Any moisture, oil, grease content on the surface has something to do with the gas formation as being under exposure of welding temperature, and can induce porosity in your weld. To fix it, wipe off the material by particular procedure of surface preparation.

3. Inappropriate gas shield

Porosity can eventuate in case of inappropriate gas shield inducing air entrapment. The welding worker is required to check the attachment of the gas hose with the equipment, and get rid of any hose contamination. Right connection would avert any gas shield loss and no air entrapment as a result. Also, draughts and air flow in the shop can lead to the gas flow restricted. There requires screening to keep away from such restrictions in the gas flow.

4. Insufficient electrode de-oxidant

In time of solidification, lower solubility can make excess oxygen release from the weld metal that then can suffer carbon monoxide formation. The porosity occurs as a result. In this case, certain de-oxidants are often added in the filler metals, electrodes, and even in the parent metals for oxygen content removal (also, de-oxidation). Thus, insufficient de-oxidants can induce bad de-oxidation and are the culprit to weld defect. For prevention, employ electrodes with sufficient de-oxidants.

5. Too high flow rate of gas shield

The flow rate of gas shield is too high, and then air can be pulled into the weld metal, which may lead to turbulence. Optimize your gas flow, offer welds of quality without gas loss. Also, it would save cost.

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5 Tips to Avoid Porosity in Welding

Find out tips to avoid porosity in welding, making sure of your weld look and durability.

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There are many welders jobs now in the market and there need more people to fill the seats. Many countries tend to reduce the flow of immigrant workers though, welding industry has wholeheartedly welcomed laborforce with this skill. To this end, job placement agencies often play a good role in helping companies find abroad workers with certain qualities they need. Employers with an eye for productivity often expect your hires to possess those traits: dedication, hard work, ability to create quality welds with minimized defects – weld porosity, for example. Just the same as the cavity in the mouth, weld porosity worsens your weld look and the repair is sometimes frustrating.

Porosity in welding occurs when a gas – often oxygen, nitrogen and/ or hydrogen, or a contaminant gets absorbed into the weld puddle. This fault would cause weak, hole-filled, bubbly welds that don’t meet code and can even make pieces of the project collapse. That's why there is no alternative but to redo such faulty welds. And it will be the best if welders can save that work by knowing how to prevent weld porosity. Below are 5 tips that may help with weld porosity prevention, especially during Mig (Gas Metal Arc Welding).

1. Keep It Clean

The material surface must be dry and clean. Oil, moisture, rust and grease are big enemy to welding. They can find ways to mix with weld puddle when the welding temperature rises, trapping gas which leads to bubbles as the material cools down.

Keep an eye on possible chemical reactions that could also cause porosity if your material gets coated with paint, zinc or other laminates. The trapped gas might be in T joints when you weld on both sides. Specially, before you begin aluminum welding, clean the outside layer of oxide.

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2. Check gas flow

Watch for the flow of shielding gas. You will have trouble if it’s too low or too high. The power of the flow is associated with the air quantity disturbed at the weld site that contaminant can mix with weld puddle.

3. Check equipment

Make sure there is no kink or leak to the hose, which can affect your shielding gas flow. Ensure the hose isn’t contaminated.

Check your gun liner to know whether it is clean and properly sized. Employ the contact tip of right size on your weld gun. Sometimes, the tip of your weld gun can be clogged, then make sure to check.

4. Maintain calm conditions

A breeze seems nice in a workshop that welding temperatures can surpass 2,500°F, but turns out to be bad for welding. Instead, keep calm conditions. Watch for strong currents and air flows, the arc length. If the gun is further away from your weld site, the gas shield can become weaker. This makes gas and air to seep into weld puddle and bubbles often appear.

5. Take it slow and steady

In Mig welding, the wire feed should seamlessly come off the reel. Check to see whether your wire feeding system has an easy-to-adjust brake and set the appropriate tension for the wire not to coast. When welding, take it slow and steady. Any haste can often induce weld porosity as the wire feed malfunctions can decelerate production.

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