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Dual Arc 82 Micro-Arc Power Supply

Process Welding Systems - Plasma and Tig Welding Solutions

DUAL PROCESS CAPABILITY FROM 0.1 TO 80.0 AMPS

MICRO PLASMA MICRO-TIG

SIMPLE PROGRAMMING AND PROGRAM STORAGE

 

 

 

 

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Pictured above: Dual Arc 82 Welding Power Supply on top, DA-WR Water cooler underneath (required for Plasma Welding Only) The system is 19.5” (50 cm) square

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The Most Capable Low Amperage Welding Systems Available

Micro -Tig System Capability:

  • •  Precision in Micro-TIG welding
  • •  Ultra low current capability (0.1 amp)
  • •  No arc wander at low amperages
  • •  Soft TIG arc start will not damage small or delicate parts
  • •  Reduced heat input thru built-in arc pulsation
  • •  Accurate, repeatable welds
  • •  Panel programmable start current, upslope, weld current, and final weld current levels
  • Manual and Automatic welding ability

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Micro—Plasma System Capability:

  • •  Micro-Plasma weld process ability offers all of the benefits of the plasma welding process (see page 2)
  • •  No Restriction to TIG or Plasma, it offers both!
  • •  Modular system can be purchased as a TIG system and later upgraded to include Plasma too
  • •  Short duration weld capability starting at 0.1 seconds
  • •  Built in computer control
  • •  Manual and Automatic welding ability

In either GTAW or PAW configuration, the Dual Arc 82 can be configured for manual or automatic welding and offers all connectivity required for automation of welding processes.

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TIG WELDING ADVANTAGES

  • •  Well-known and understood process
  • •  Readily available, low cost consumable parts
  • •  Excellent gas shielding for smaller parts
  • •  Electrode can be extended for improved weld joint access
  • •  “Soft” TIG arc can offer benefits for certain applications
  • •  More forgiving of part fit-up problems in certain applications————————————————————————

PLASMA WELDING ADVANTAGES

  • •  Protected electrode allows for more welds before electrode contamination
  • •  Arc gap distance not as critical as in TIG
  • •  “Gentle” arc transfer
  • •  Stable, stiffer arc reduces arc wander
  • •  No high-frequency arc starting noise
  • •  Extremely short duration welds possible for spot welding of wires, needles and micro components
  • •  Higher weld speeds in specific applications

 

Applications

And Many More

Valves, metal seals, diaphragms, pressure transducers, sensors, implant devices, relay cans capacitor cans, Micro switches, motors, electronic devices, enclosures, explosive detonators, airbag components, air seals, tube/ fitting assemblies, vacuum tubes, electrocautery tools, metal meshes, pacemakers, thermocouples, tube closure, surgical instruments, dental instruments, wires, aspiration needles, injection needles, surgical baskets, catheter metal capsules, guidewires, light bulb filaments, and more.

Read More

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Standardization of Welding Procedures

Weld Engineering has recently directed manufacturing engineering to adopt weld standardization into the production work cell. Weld standardization is a consistent and uniform approach to a given welding application. Standardization is divided into two critical components that include Process and Producibility. It is important to recognize that process control should remain independent of the theoretical approach utilized for a given welding application. The first step is to clone every element of each workstation in order to achieve the same process identity throughout production. The second component of standardization is Producibility. Producibility is simply the pursuit of a weld applications procedural limit. With each material there exists a weldability range in which a satisfactory weld can be produced. The candidate material or application is welded at a variety of speeds and parameters. Observations are documented as the window of Producibility is pushed to its maximum limit. This continues until some aspect of acceptance criteria is no longer satisfied. It is at this point that the low, middle, and upper control limits of the process are established. Standardization substantiates a company’s commitment to further product quality and establishes a basis for comparing quantity and quality. Qualification by similarity is one of the many benefits of standardization. Process Welding Systems Welding Positioner's are second to none. Call us today and ask about them and how best to improve the quality of your product production.

Welding Positioners

 

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Costs of an Automated Welding System.

Basic parameters:

Operator and skilled welder salaries vary somewhat according to geographic locations. The basic assumptions used in the calculations below are as follows:
Work hours per year: 2000 (40 hours/week x  50 weeks/years)
Manual welder Costs
Average welder pay:     $16/hour (range from $14/hour - $18/hour)
Actual welder cost to employer:       $24/hour equals $48,000/year
(1.5 X hourly rate for overhead, vacation, holidays, sick time, Social Security, unemployment taxes, insurance, etc.)

Operator Costs
Average operator pay:       $10/hour (range from $8/hour - $12/hour)
Actual cost to employer:  $15/hour equals 30,000/year
(1.5 X hourly rate for overhead)

The table below gives a simple example of calculations for return or investment based on equipment and labor costs alone. For a full analysis of actual costs the following must also be considered;

• Actual equipment cost • Labor rates • Production welding speeds possible • Supervisor cough • Personal management • Quality control costs • Reject and scrap cost • Customer relations •

Number of systems required for the call output.

8x

4x

1x

Individual system cost
Total equipment system investment

$5,000
$40,000

$32,000
$128,000

$200,000
$200,000

Individual welder cost/year
Individual operator cost/year
Labor cost/year for equal volume of output.
(One 8 hour shift)

$48,000

 

$384,000

 

$30,000

$120,000

 

$30,000

$120,000

Labor and equipment cost for a 12 month
period with one eight hour shift

$424,000

$248,000

$230,000

Labor and equipment cost for a 12 month
period with one eight hour shift

$808,000

$368,000

$260,000

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Carbon Steel – Welding

 

Carbon steel is steel where the main interstitial alloying constituent is carbon in the range of 0.12-2.0%. The American Iron and Steel Institute (AISI) defines carbon steel as the following: "Steel is considered to be carbon steel when no minimum content is specified or required for chromium, cobalt, molybdenum, nickel, niobium, titanium, tungsten, vanadium or zirconium, or any other element to be added to obtain a desired alloying effect; when the specified minimum for copper does not exceed 0.40 percent; or when the maximum content specified for any of the following elements does not exceed the percentages noted: manganese 1.65, silicon 0.60, copper 0.60."

 

 Mild and low carbon steel

Mild steel, also called plain-carbon steel, is the most common form of steel because its price is relatively low while it provides material properties that are acceptable for many applications, more so than iron. Low carbon steel contains approximately 0.05–0.3% carbon[1] and mild steel contains 0.3–0.6%[1] carbon; making it malleable and ductile. Mild steel has a relatively low tensile strength, but it is cheap and malleable; surface hardness can be increased through carburizing.[3]

Higher carbon steels

Carbon steels which can successfully undergo heat-treatment have a carbon content in the range of 0.30–1.70% by weight. Trace impurities of various other elements can have a significant effect on the quality of the resulting steel. Trace amounts of sulfur in particular make the steel red-short, that is, brittle and crumbly at working temperatures. Low alloy carbon steel, such as A36 grade, contains about 0.05% sulfur and melts around 1426–1538 °C (2599–2800 °F).[8] Manganese is often added to improve the hardenability of low carbon steels. These additions turn the material into a low alloy steel by some definitions, but AISI's definition of carbon steel allows up to 1.65% manganese by weight.

 

Medium carbon steel

Approximately 0.30–0.59% carbon content.[1] Balances ductility and strength and has good wear resistance; used for large parts, forging and automotive components.[9]

High carbon steel

Approximately 0.6–0.99% carbon content.[1] Very strong, used for springs and high-strength wires.[10]

Ultra-high carbon steel

Approximately 1.0–2.0% carbon content.[1] Steels that can be tempered to great hardness. Used for special purposes like (non-industrial-purpose) knives, axles or punches. Most steels with more than 1.2% carbon content are made using powder metallurgy. Note that steel with a carbon content above 2.0% is considered cast iron.

Heat treatment

The purpose of heat treating carbon steel is to change the mechanical properties of steel, usually ductility, hardness, yield strength, or impact resistance. Note that the electrical and thermal conductivity are only slightly altered. As with most strengthening techniques for steel, Young's modulus (elasticity) is unaffected. All treatments of steel trade ductility for increased strength and vise versa. Iron has a higher solubility for carbon in the austenite phase; therefore all heat treatments, except spheroidizing and process annealing, start by heating the steel to a temperature at which the austenitic phase can exist. The steel is then quenched (heat drawn out) at a high rate causing cementite to precipitate and finally the remaining pure iron to solidify. The rate at which the steel is cooled through the eutectoid temperature affects the rate at which carbon diffuses out of austenite and forms cementite. Generally speaking, cooling swiftly will leave iron carbide finely dispersed and produce a fine grained pearlite (until the martensite critical temperature is reached) and cooling slowly will give a coarser pearlite. Cooling a hypoeutectoid steel (less than 0.77 wt% C) results in a lamellar-pearlitic structure of iron carbide layers with _-ferrite (pure iron) between. If it is hypereutectoid steel (more than 0.77 wt% C) then the structure is full pearlite with small grains (larger than the pearlite lamella) of cementite scattered throughout. The relative amounts of constituents are found using the lever rule. The following is a list of the types of heat treatments possible:

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There Are Differences in Welding

Difference Between MIG and TIG Welding

The Basic difference between MIG and TIG welding is that one uses consumable wire electrode (MIG) and other (TIG) uses non-consumable tungsten electrode. In MIG welding process, electric arc is produced between a consumable wire electrodes and workpiece metals. And in TIG welding process, electric arc is produced between a non-consumable tungsten electrode and workpiece metals. The heat generated by the arc is used to melt the metals and forms weld. Here we will discuss all the major differences among MIG and TIG Welding.
Difference Between MIG and TIG Welding

Difference Between MIG and TIG Welding

Here we have learnt all the major difference between MIG and TIG welding. If you have any questions regarding this article than comment us at Process Welding Systems.

S.no
MIG Welding
TIG welding
1.
MIG stands for Metal Inert Gas Welding. It is also known as Gas Metal Arc Welding (GMAW), Metal Active Gas Welding (MAG).
TIG stands for Tungsten Inert Gas Welding. It is also known as Gas Tungsten Arc Welding (GTAW).
2.
It is a welding process in which electric arc is formed in between a consumable wire Electrode and workpiece metal(s).
It is a process in which an electric arc is formed in between a non-consumable tungsten electrode and workpiece metal(s)
3.
The type of electrode used is consumable wire electrodes.
The type of electrode used is non-consumable tungsten electrode.
4.
Most commonly it uses constant voltage, direct current power source for the welding. It can also use constant current system and alternating current.
It uses constant current welding power supply for the welding.
5.
The materials which it can weld are aluminum, non-ferrous materials and steels.
It is most commonly used to weld stainless steels and non-ferrous metals like aluminum, magnesium and copper alloys.
6.
High skilled operator is not required to perform MIG welding process.
High skilled operator is required to perform TIG welding process.
7.
It has high weld deposition rate.
It has low weld deposition rate as compared with MIG welding.
8.
No filler metal is required. The feed electrode wire melts and acts as filler metal.
It may require filler metal from outside in some cases if needed.
9.
It can weld thick metal sheets up to 40 mm.
It can weld thin metal sheets up to 5 mm.
10.
It produces less quality of weld as compared with TIG.
It produces high quality of weld because it affords greater control over weld area.
11.
It uses continuous wire feed.
It does not uses continuous wire feed.
12.
The equipment used in MIG welding process is a welding gun, a welding power supply, a feed wire unit, a welding electrode wire and a shielding gas supply.
The equipment used in TIG welding process is welding torch, non-consumable tungsten electrode, a constant-current welding power supply and a shielding gas source.
13.
It is a faster welding process.
It is a slower welding process.
14.
In this welding process, the use of filler metal is compulsory.
But in this welding process the filler metals may or may not be used. There is no compulsion of using filler metals, it is used when required.
15.
 It cannot work in any position.
It can be worked in any position.
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TIG Welding – Beginners Guide

We are always interested in our customer’s welding product needs. To maintain it’s growth pattern PWS has developed a variety of products and many of the products we offer are of a “value added” nature. PWS is able to assist customers in improving their production processes through equipment to enhance or improve welding quality.

These activities serve to broaden the product and services offering and make the company less dependent on outside sources for development. The acceptance of new equipment has been researched and appears to be welcomed consideration to the current customer base. Continual product development will ensure balanced growth and recognition as a source of expertise in welding equipment and processes.

SERVICES INCLUDE:
 Design services for precision welding systems (manual load/unload or semi-automatic)
 Integration of welding system accessories & site installation assistance
 Experienced staff for custom design & manufacture of tooling, fixtures & specialty torch nozzles
 Free weld application review & process recommendation

TECHNICAL SUPPORT:
 Troubleshooting, maintenance & repair of equipment
 Weld training – skills development
 Weld development – material evaluation, joint design, weld parameter development
 Comprehensive consumable inventory stock of replacement parts for plasma power supplies, accessories & plasma welding torches

CUSTOM PRODUCTS AND ACCESSORIES:
Special gas shields – MIG, TIG & Plasma
Torch slides – X, Y, Z

TIG Welding – Beginners Guide

TIG welding is probably he most complicated type of welding there is, and for a beginner the shear number of variable can be a bit confusing. Below is a break down on all the different areas with some “numbers” to help you get started.

TIG Welding – Beginners Guide – Gas

Now you may think talking about gas before the welder is odd, but bear in mind that if you are on a budget then the gas is going to represent a significant outlay.

Unlike MIG welding TIG welding can only use pure argon (or other specialist gases), so using food grade CO2 for example is not possible.

TIG Welding – Beginners Guide – Welders

Make sure that the welder actually comes with a proper TIG torch, as some Arc Welders can be used for TIG welding but do not come supplied with a TIG torch as pictured below.

A TIG Torch

TIG Welding – Beginners Guide – The Tungsten

The tungsten is the electrode that sticks out of the front of the torch. Confusingly there are various different types, that are better suited to different applications. Your welder may come supplied (as mine did) with an unsuitable tungsten electrode. Most people suggest a 2% thoriated tungsten, but this is radioactive, so perhaps go for a 1-2% lanthanated electrode which I believe performs similarly. 

You should sharpen your tungsten before first use. 

OK so hopefully that covers the gear now a little on technique.

TIG Welding – Beginners Guide – Holding the Tig Torch  

To avoid damaging the electrode, you will need to hold it around 2 – 3mm from the working surface. With a welding mask on this is no mean feat, and will take a great deal of practice to get the hang of. The torch should be held in a way that is very comfortable;

Index Finger on Top
Or like a pencil

Gloves should be used or you will get sun burn from the UV radiation emitted from the arc. If you are working on a large item, it may heat up meaning you will need something heat proof to rest your hand on.

The torch should be held with the electrode as upright as  possible, whilst still allowing you to see what you are doing.

TIG Welding – Beginners Guide – Setting the Amperage

On the most basic of TIG welders there will be an amperage control, too little amperage and you will not melt the metal, too much and you make a hole.

It is recommended around 65 amps for 16 gauge steel  (1.63mm). So a bit more for thicker stuff, and a bit less for thinner stuff, remember that the maximum amperage you can use will be limited by the diameter of the tungsten you are using. 1.6mm tungsten will go up to around 90 amps, if you intend to use more amps then get a thicker electrode.

The better the conductivity of the metal the higher your amperage will have to be, aluminum requires a higher amperage that steel for the same thickness.

TIG Welding – Beginners Guide -Gas Flow Rate

During welding set gas flow around 7 – 8 liters per minute.

PROCESS WELDING SYSTEMS AUTOMATED WELDING SYSTEMS TAKE YOU TO THE NEXT LEVEL:

Our automated system helps  you increase welding quality, improve welding productivity, enhance the working environment and decrease manufacturing cost.

Special Purpose Machines (SPM) with simple timer and contractor control to complex designs using CNC controllers, servo motors, pneumatics, hydraulics as requirement.

Process Welding Systems’ design, manufacture and sell complete weld automation stations for mass production with automated welding of various components , equipments, overlay metal build up, hard-facing and metal spray applications .

See our CUSTOM AUTOMATED LATHE

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Let Us Know More About You

We are always interested in our customer’s welding product needs. To maintain it’s growth pattern PWS has developed a variety of products and many of the products we offer are of a “value added” nature. PWS is able to assist customers in improving their production processes through equipment to enhance or improve welding quality.

These activities serve to broaden the product and services offering and make the company less dependent on outside sources for development. The acceptance of new equipment has been researched and appears to be welcomed consideration to the current customer base. Continual product development will ensure balanced growth and recognition as a source of expertise in welding equipment and processes.

SERVICES INCLUDE:
 Design services for precision welding systems (manual load/unload or semi-automatic)
 Integration of welding system accessories & site installation assistance
 Experienced staff for custom design & manufacture of tooling, fixtures & specialty torch nozzles
 Free weld application review & process recommendation

TECHNICAL SUPPORT:
 Troubleshooting, maintenance & repair of equipment
 Weld training – skills development
 Weld development – material evaluation, joint design, weld parameter development
 Comprehensive consumable inventory stock of replacement parts for plasma power supplies, accessories & plasma welding torches

CUSTOM PRODUCTS AND ACCESSORIES:
Special gas shields – MIG, TIG & Plasma
 Torch slides – X, Y, Z
 Special plasma nozzles – custom sizes
 Contract welding
 Tungsten electrode grinders

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Plasma Spare Parts

Plasma Welding Parts

At Process Welding Systems we offer spare parts for over a dozen different plasma torches. If it is a plasma welding torch we probably have spare parts for it.

We offer:

  •  Ceramic gas cups, centering pieces, sleeves
  •  Tungsten electrodes, pre-sharpened to customer specifications
  •  Copper welding nozzles of various sizes
  •  Custom length plasma torches
  •  Custom fittings on plasma torches

 

Not only are we your plasma welding experts but we also offer:

  •  Off the shelf plasma power supplies
  •  Custom welding packages
  •  Weld lab assistance for our customers
  •  Fully automated, semi-automated welding systems
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We Offer Tungsten Electrodes for Tig and Plasma Welding.

Announcing the sale of high quality, low cost tungsten electrodes for GTAW and PAW welding.  Thoriated, ceriated and lanthanated electrodes are in stock.

Both TIG and Plasma processes require tungsten electrodes to generate the arc for welding. For most applications, 2% Thoriated tungsten has been used as the general purpose electrode material. With this electrode almost all materials can be welded including aluminum.

Over the past few years, several other tungsten electrode types have been formulated that offer specific advantages for certain applications. Cerium has replaced Thorium for a tungsten alloy that offers great arc starting performance with no radioactivity like thorium. Lanthanum has also been added to improve arc starting and offers better performance for certain applications.

Here is a quick reference table with the advantages of each tungsten type;

2% Thoriated Tungsten (color Red)

  •  The standard for most applications, but is slightly radioactive. Works well for DC welding and can be used for AC welding on aluminum for non-critical applications. Has some tendency to split if used for aluminum and the electrode is contaminated.
  • Medium to good wear rates and low current arc starting capabilities
  • Good general purpose electrode

 

 

2% Ceriated Tungsten (color Grey)

  • Electrode is not radioactive and offers excellent DC welding capabilities. Can also be used for AC welding of aluminum.
  • Excellent low wear rates and excellent low current DC capabilities
  • Excellent arc starting properties

 

 

2% Lanthanated Tungsten (color Blue)

  • Electrode is non radioactive and offers excellent DC and AC welding capabilities. Can be used for AC welding of aluminum.
  • Excellent low wear rates and excellent low current DC capabilities
  • Excellent arc starting properties

The proper choice of electrode type can improve welding processes by offering improvements in arc starting and offering longer life between re-sharpening. For very low current applications, the Ceriated and Lanthanated Tungsten Electrode materials can give much better performance.

 

Our Electrodes are ready for purchase over the internet or by purchase order.  Discounts are available on orders of 10 or more boxes. The tungsten electrodes are 7” long and diameter sizes from 0.020 up to 1/8”. Visa, Mastercard and American Express orders are accepted. Contact us for pricing, technical information or free tungsten electrode samples.

 

Process Welding Systems also offers Plasma and Tig welding power supplies, weld programmers, plasma welding torches, welding lathes and positioning devices. Custom automation systems, custom welding systems are designed and built to meet demanding customer specifications with accuracy  and consistent weld quality results. Complimentary sample welding and weld development assistance are standard services.

For further information call or write: Process Welding Systems Inc., 72 Buchanan St., LaVergna, TN 37086. Phone: 615-793-7020, Fax: 615-793-7557, Email: sales@processwelding.com  www.processwelding.com

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LOW AMP PLASMA WELDING

LOW AMP PLASMA WELDING

CHECK LIST FOR CONTAMINATED ELECTRODE, DIRTY WELD NOZZLES AND PLASMA TORCH CARE.

  1. A dark blue or black tungsten (Figure B) is a sign of moisture or oxygen getting into the plasma gas line (also called the pilot gas line). If the gas is good quality and the gas lines are leak free the tungsten should remain a gray color (Figure A) not dark blue or black. Moisture and oxygen in the gas lines deteriorate the tungsten electrode and thus the number of arc starts that the tungsten electrode can produce is reduced. This cuts down on the number of arc starts in production and decreases production.
  2. Any leaks in the gas lines or fittings can allow air to be sucked into the gas system which adds oxygen and moisture to the welding gases being used. Levels of oxygen and water should be less than 5ppm. The most important gas in plasma welding is the pilot gas, also called plasma gas, is always argon gas. The grade of argon being used should be at least 99.998% pure argon. In plasma welding if the gas is not pure it will contaminate the tungsten electrode and turn the tungsten electrode a dark blue and black color. If the problem is very severe the discoloration will run all the way to the point of the tungsten electrode and the nozzles on the torch will clog up.
  3. Tocheckforgasleaksoneneedstoinstallabottleofgasonthepilotgasline and it is recommended that the gas bottle is used with a dual stage regulator with a stainless steel diaphragm. Next take a nozzle for the torch and solder the orifice of the nozzle closed. Clean the nozzle after soldering with acetone or alcohol and install a small o’ring that will make a seal when the nozzle is screwed into the torch and hand tightened Also make sure that where the nozzle seats against the torch body is clean and free of dirt. If the nozzle does not seat well against the torch body a gas leak can occur. Turn the pilot gas flowmeter up to its highest flow and turn off the argon gas bottle. This will

trap gas in between the tip of the torch nozzle and the argon gas bottle. Take a reading on the high pressure gas gauge of the gas regulator. Wait 15 to 30 minutes. If the gas system is leak free the gauge reading will stay the same as when the gas bottle was turned off. If the gauge pressure drops then there is a gas leak in the system. The leak could be caused by a hole in the gas hoses or defective fittings and gaskets.

  1. If the system has a leak you must then go through and check fittings to make sure they are tight and make sure that gaskets are sealing. You can also pinch the plastic hose where the torch connects and trap gas from where the hose is pinched back to the regulator and see if still leaks thus working your back through the gas system.
  2. Check for cracks in the torch body. If the torch has a back cap check the o’ring on the cap and check the cap for holes or cracks.
  3. After it has been determined that the gas system is leak free the system needs to be purged. By purging the gas lines it will clean all of the moisture and oxygen out of the lines so that you will only have good clean gas in the system. Turn the pilot gas flow up to its highest flow rate and let the gas run through the lines for at least 30 minutes to and hour. Next start a pilot arc and let it run at normal pilot arc gas settings (0.4 to 0.6 liters per minute) for 10 minutes. Turn off the pilot arc and check to see if the color of the tungsten electrode is gray. If it is gray your gas system is clean. If the color is black and blue then the system needs to purge longer to make sure it is clean.
  4. If your welding system is shut down over night air with oxygen and moisture will get up inside the plasma torch. Before starting to weld on the next day you need to again purge the gas lines approximately 5 to 10 minutes before starting to weld. You may want to turn the pilot gas down to a very low flow such as 0.1 liters per minute and let the gas run all night to keep the gas line clean. It will be such a low flow that it will not be of any economic importance.
  5. When the pilot arc is turned off let the gas continue to flow for at least 10 to 15 seconds before turning off main power. The gas flow will keep the tungsten electrode from oxidizing until it cools down.
  6. Whenever thinking about electrode life, electrode contamination, ease of arc starting and arc stability you should not forget that the exchange of ions takes place within the plasma column in both directions which is from the electrode to the work piece and from the work piece to the electrode. If impurities such as lead, sulfur, aluminum, magnesium, copper, zinc, brass, oil, grease or any other dirty elements are on or in the material being welded they will contaminate the tungsten electrode and nozzle. You then cannot count on a maximum number of welds before replacing the tungsten electrode and weld nozzle.

10. Clean the nozzle orifice with acetone or alcohol and a Q-tip. A round wooden toothpick can be used to clean the orifice of the nozzle. Weld nozzles trap contamination during welding and will need to be cleaned every time the tungsten is re-ground.

11. The pilot arc should be bright white with a light blue tint color. If the color changes to orange or purple that is a sign of contamination. Also the pilot arc

will draw back into the nozzle, which is a sign that the tungsten electrode has

deteriorated.
12. WARNING: It is extremely important that when tightening the nozzle onto the

torch head that you do not over tighten the nozzle and strip the threads. Copper is a very soft material, which makes it easier to over tighten the nozzle. Tighten the nozzle until it barely makes intimate contact with the end of the torch head. It is recommended that pliers be used to tighten the nozzle but be careful not to grab the torch head with the pliers. Also be careful not to cross thread the nozzle. If the nozzle is cross threaded it will damage the threads inside the torch head. Do not get dirt, grease or oil inside the torch head or on the nozzle threads, which will damage the threads in the torch head. If the torch head is damaged by the pliers it can cause a gas leak between the nozzle and torch head and the nozzle will not seat properly against the water cooled part of the torch head. If the threads are stripped and the torch head is damaged the torch will have to be replaced. Periodically clean the inside of the torch and thread where the nozzle seat with alcohol of acetone. Make sure that the technician that handle the torch and installs nozzles hands are clean. Dirt, oil, grease and grit is not acceptable on any of the torch parts. The plasma welding torch is an expensive device and should handled with great care.

13. The type of hose material that the pilot gas and shield gas are passed through is very important. All plastics can have moisture and oxygen that diffused through the walls of the hose material. When welding sensitive materials such as titanium the welding system may need to plumbed with stainless steel gas lines.