Welding method using Tungsten non consumable electrode (TIG) is a very important way using in a wide range. By this article, we

would like to make some brief introduction of the TIG welding torch using tips. Compare with SMAW, the TIG weld torch is more

complicated & the price is higher. Normally it is composed by gun body, nozzle, collet, collet body, cable, gas input pipe, cooling

water inlet pipe, weld gun control switch and so on. The price range is from hundreds to thousands USD depends on the model &

type.Correct using & maintenance the weld gun is very helpful to the welding quality, also is a good guarantee of the safety. 

 

II.TIG weld gun type
 

1. By cooling method, ① air cooling (self cooling), normally used for welding current under 200A, usually the model with QQ. ② water

cooling (cycling, non cycling), normally used in big welding current, long working duration, auto welding occasion, usually the model

with PQ, QS etc letters. 

 

2. By gas venting angle, ①0° pencil type, usually used for pit, deep hole,narrow position welding. ②65～85° fixed type, usual welding

position.③ flexible (winding, adjustable,rotary, universal ), it could be random adjusted 0～90°  , easy operation, suitable for each

kind of position, while its using life could not reach as long as fixed type. 

 

TIG weld torch weight usually 0.07～0.5kg (exclude double layer nozzle,towing hood etc), control switch including push type, knob,

hull type & micro switch etc.  Tungsten electrode length usually is 40~160mm, usually welding current 10~500A. 

 

III.TIG weld gun using tips
 

1.Basic requirement ①fasten clamp electrode. ② conduct weld current.③ output protection gas (Ar, He, Ar+He, Ar+H2). 

 

2.detail requirement :① maintain the gas with certain stiffness, so the air flow blowing from the gun with well protection performance.

② well conduction characteristics, enough loading capacity, satisfy with certain capacity requirement, good radiating, ensure

persistent working, using water cooling gun when necessary. ③ Easy for electrode install &dismantle. Electrode must be at center of

the nozzle. ④ nozzle & gun must be insulating, protect from short circuit. Especially using E-CU nozzle with big welding current, the

insulating should be secure. ⑤ whole gun structure should be simple, light, easy approaching weld seam, easy to surveillance weld

poll. ⑥ it is better to reserve installation hole for towing hood, double layer nozzle etc attachment, in favor of the accessory

installation afterward when reinforce the protection effect required. 

 

IV. nozzle tips
 

1. nozzle type:① by shape,there is cylinder type,max effective protection zone, max application range;  convergent type(back taper

shape), used for small weld current or narrow place welding; diffusing type(conical), not too much in application, usually used for melt

gas shield welding.  ② by material, there is ceramic type,good insulating & good heat resistance, wide application, while the welding

current should not be over 300A;  E-Cu, big welding current, upto 550A; quartz, good visual ability, cost is higher. 

 

2. The inner wall polishing degree is very important. The splash etc impurity on the inner wall, not just influence the weld seam quality

by falling into the molten pool, but also would block the protection gas flow & distribute the air flow, therefore the nozzle should be

clean up or replaced timely. 

 

V. Tungsten electrode tips. 
 

1. Electrode material: usually the material includes pure tungsten, cerium tungsten, thorium tungsten, lanthanum tungsten,zirconium

tungsten etc.   Pure tungsten/zirconium tungsten usually is used for AL/Mg metal welding. Cerium tungsten/lanthanum tungsten is the

most common using.  Thorium tungsten usually is used for big weld current or auto welding. 

 

2. Electrode tip shape: usually grinding angle is 20～90°, smaller welding current, smaller angle, bigger welding current, bigger angle.

For AC weld power source or DCRP, the top should be roundness. 

 

VI. Tips of accessories to strength the protection effect
 

When welding high requirement weldment, using big welding current, especially welding active metal like Ti,Zr, the protection should

be remain until temperature under 316℃（Ti）、200℃（Zr）, to avoid weld seam oxidation. Under this situation, special

accessories are required. 

 

1.Double layer nozzle (outer nozzle): the most frequently using, easy to make. Using for high protection requirement & big weld

current occasion. 

 

2. Towing hood (following protection), mainly used for active metal welding, shape includes linear, arc, special shape etc.  The match

up between weld speed & towing hood length should properly take care so as to reach optimal effect.  

 

3. For pipeline, vessel welding, inner full filling protection gas. For plate butt welding, usually using pad with protection gas filling. For

convex weld position, using block to improve protection effect. 

 

VII.Tips of TIG weld gun choosing
 

By choosing a idle TIG weld gun, following factors should be proper considered: weld job material, job angle, weld bead layer,

welding current type (DC/AC), electrode diameter, beveling edge form, weld speed, weld joint position, economical factor and so on.

  Auto TIG weld usually is using pencil type water cooling weld gun. For special weld position, tailor made special weld gun or restore

of weld gun in hand is necessary.