AC TIG DC TIG

TIG Welding:

AC TIG is generally used to weld aluminum and magnesium materials. For the best appearance, highest quality and leak free welds on aluminum, AC TIG welding is the process of choice. The primary gas used is argon and in some applications on thick aluminum when additional penetration is needed an argon/helium mixture or pure helium is used. TIG welding offers the user the greatest amount of flexibility to weld the widest range of material and thickness. AC TIG welding is also the cleanest weld with no sparks or spatter.

DC TIG is generally used to weld exotic material like stainless steel, nickel alloys, copper, titanium and critical welds that must be flawless such as aircraft engine parts. The primary gas used is argon and in some applications an argon/helium mixture or pure helium is used. TIG welding offers the user the greatest amount of flexibility to weld the widest range of material and thickness and types. DC TIG welding is also the cleanest weld with no sparks or spatter.

What if I have problems TIG Welding? TIG Welding Tips

TIG Welding Tips

What if I have problems TIG Welding?

The following chart addresses some of the common problems of TIG welding. In all cases of equipment malfunction, the manufacturer's recommendations should be strictly adhered to and followed.

PROBLEM 1: Burning Through Tungsten Fast
PROBABLE CAUSES	SUGGESTED REMEDY
1. Inadequate gas flow.	Check to be sure hose, gas valve, and torch are not restricted or the tank is not out of gas. Gas flow should typically be set at 15 to 20 cfh.
2. Operating on electrode positive (DCEP).	Switch to electrode negative (DCEN).
3. Improper size tungsten for current used.	General purpose tungsten size is 3/32" diameter at a maximum of 220 amps.
4. Excessive heating in torch body.	Air-cooled torches do get very warm. If using a water-cooled torch, coolant flow may be restricted or coolant may be low.
5. Tungsten oxidation during cooling.	Keep shielding gas flowing 10–15 seconds after arc stoppage. 1 second for each 10 amps of weld current.
6. Use of gas containing oxygen or CO2.	Use Argon gas.
7. Tungsten melting back into cup (AC).	If using pure  tungsten, change to ceriated  or lanthanated . If machine has Balance Control, adjust setting towards maximum penetration (70-90). Tungsten diameter may be too small for the amount of current being used. Increase tungsten size.
PROBLEM 2: Tungsten Contamination
PROBABLE CAUSES	SUGGESTED REMEDY
1. Tungsten melting into weld puddle.	Use less current or larger tungsten. Use ceriated  (AC) , thoriated  (DC), or lanthanated  tungsten.
2. Touching tungsten to weld puddle.	Keep tungsten from contacting weld puddle. Raise the torch so that the tungsten is off of the work piece 1/8" to 1/4".
PROBLEM 3: Porosity and Poor Weld Bead Color
PROBABLE CAUSES	SUGGESTED REMEDY
1. Condensation on base metal.	Blow out all air and moisture condensation from lines. Remove all condensation from base metal before welding. Metals stored in cold temperatures will condensate when exposed to warm temperatures.
2. Loose fittings in torch or hoses.	Tighten fittings on torch and all hoses.
3. Inadequate gas flow.	Adjust flow rate as necessary. Gas flow should typically be set at 15 to 20 cfh.
4. Defective gas hose or loose connection.	Replace gas hose and check connections for leaks, cuts, or pin holes.
5. Contaminated or improper filler metal.	Check filler metal type. Remove all grease, oil, or moisture from filler metal.
6. Base metal is contaminated.	Remove paint, grease, oil, and dirt, including mill scale from base metal.
PROBLEM 4: Yellow Powder or Smoke on Cup—Tungsten Discolor
PROBABLE CAUSES	SUGGESTED REMEDY
1. Shielding gas flow rate too low.	Increase flow rate. Gas flow should typically be set at 15 to 20 cfh.
2. Incorrect shielding gas or mixture.	Use argon gas.
3. Inadequate post flow.	Increase post flow time. Set at 10 to 15 seconds.
4. Improper tungsten size or cup size.	Match tungsten size and cup size to joint being welded. General purpose tungsten size is 3/32" diameter and #8 cup.
PROBLEM 5: Unstable Arc
PROBABLE CAUSES	SUGGESTED REMEDY
While DC Welding
1. Weld circuit polarity is incorrect.	Check polarity switch on welder. Select DCEN (Direct Current Electrode Negative).
2. Tungsten is contaminated.	Remove 1/2" of contaminated tungsten and repoint tungsten.
4. Arc too long.	Shorten arc length. Lower torch so that the tungsten is off of the work piece no more than 1/8" to 1/4".
5. Base metal is contaminated.	Remove paint, grease, oil, and dirt, including mill scale from base metal.
While AC Welding
1. Excessive rectification in base metal.	Increase travel speed. Increase balance control toward more penetration. Add filler metal.
2. Improper shielding gas.	In some cases, when welding on 3/8" to 1/2" thick aluminum, argon/helium is used.
3. Incorrect arc length.	Use correct arc length. Adjust the torch so that the tungsten is off of the work piece 1/8" to 1/4".
4. Tungsten is contaminated.	Remove 1/2" of contaminated tungsten and repoint tungsten.
5. Base metal is contaminated.	Remove paint, grease, oil, and dirt, including mill scale from base metal.
6. Frequency set too low.	On welders with adjustable AC frequency, increase frequency to give proper arc stability and direction. 100 to 180 Hertz is acceptable.
7. Improperly prepared tungsten.	With Squarewave and inverter machines, use pointed tungsten. Point will eventually round off after welding.
PROBLEM 6: High-Frequency Present — No Arc Power
PROBABLE CAUSES	SUGGESTED REMEDY
1. Incomplete weld circuit.	Check work connection. Check all cable connections.
2. No shielding gas.	Check for gas flow at end of torch. Check for empty cylinder or closed shut-off valve. Gas flow should typically be set at 15 to 20 cfh.
PROBLEM 7: Arc Wanders
PROBABLE CAUSES	SUGGESTED REMEDY
While DC Welding
1. Improper arc length/tungsten in poor condition.	Lower the torch so that the tungsten is off of the work piece 1/8" to 1/4". Clean and sharpen tungsten.
2. Improperly prepared tungsten.	Grind marks should run lengthwise with tungsten, not circular. Use proper grinding method and wheel.
3. Light gray frosted appearance on end of tungsten.	Remove 1/2" of tungsten and repoint tungsten.
4. Improper gas flow.	Gas flow should typically be set at 15 to 20 cfh.
While AC Welding
1. Improper tungsten preparation.	With Squarewave and inverter machines, use pointed tungsten. Point will eventually round off after welding.
2. Tungsten is contaminated.	Remove 1/2" of contaminated tungsten and repoint tungsten.
3. Base metal is contaminated.	Remove paint, grease, oil, and dirt, including mill scale from base metal.
4. Incorrect balance control setting.	Increase balance toward more penetration. Normal Balance Control setting is 70 - 90.
5. Improper tungsten size and type.	Select proper size and type. General purpose tungsten size is 3/32" diameter and ceriated  or thoriated .
6. Excessive rectification in base metal.	Increase travel speed. Increase balance setting toward more penetration. Add filler metal.
7. Improper shielding gas flow.	Gas flow should typically be set at 15 to 20 cfh.
8. Frequency set too low.	Increase AC frequency on machines so equipped to stabilize and direct the arc. The higher the frequency, the narrower and deeper the penetration.
PROBLEM 8: Arc Will Not Start or is Difficult to Start
PROBABLE CAUSES	SUGGESTED REMEDY
While DC Welding
1. No shielding gas.	Gas flow should typically be set at 15 to 20 cfh.
2. Incorrect power supply switch positions.	Place switches in proper positions, either HF impulse or start HF.
3. Improper tungsten electrode.	Use ceriated  or thoriated  tungsten.
4. Loose connections.	Tighten all cable and torch connections.
5. Incomplete weld circuit.	Make sure work clamp is connected.
6. Improper tungsten size.	Use smallest tungsten possible. Most common tungsten size is 3/32" diameter.
While AC Welding
1. Incomplete weld circuit.	Check work clamp to assure it is securely fastened to work.
2. Incorrect cable installation.	Check circuit breakers and fuses. Check and tighten all cable connections.
3. No shielding gas.	Check for gas flow at end of torch. Check for empty cylinder or closed shut-off valve. Gas flow should typically be set at 15 to 20 cfh.
4. Loss of high frequency.	Check torch and cables for cracked insulation or bad connections. Check spark gaps and adjust if necessary.
5. Improper tungsten size.	Use smallest tungsten possible. Most common tungsten size is 3/32" diameter.
6. Incorrect tungsten type.	Use ceriated , thoriated , or lanthanated  tungsten.

 

MOS inverter air plasma welder Air Inverter Plasma Cutter Inverter-Based Plasma Cutter

MOS inverter air plasma welder
Air Inverter Plasma Cutter

Inverter-Based Plasma Cutter 

Industrial Welders Plasma

This cutter delivers high performance regardless of whether it is used for industrial, construction and home environments.

In addition, this cutter is quite portable and simple to maintain and clean. While in use, it has elements of safety, with minimal fire risks and production of pollutant gases.

This review provides you with relevant information to help you select a quality cutting machine that is very efficient. With reference to customer reviews, the LT5000D Lotos 50A Air Inverter Plasma Cutter Dual Voltage is analyzed in light of its features and performance.

After reading this review, there is assurance that with increased knowledge on the cutter, you will be in a position to make a well-advised decision on the cutter to settle on for cutting metals.


Pros

 50A dual voltage 110/220v AC digital inverter plasma cutter that is designed to withstand extensive use in industrial, construction and home use.
The cutter is very easy to clean and maintain and is very safe to use.
With a reduced fire hazard and lower noxious gases, the machine can safely produce better, cleaner cuts.
The torch trigger in the machine can be adjusted for customized use either in finger or thumb positions.
The cutter is very portable and therefore it is easily used with minimal fatigue. This cutter can cut through thicker material at high frequency with no distortions on the workpiece.
The MOSFET transistors provide high power output for thick metal cutting and steady output for thin metal cutting.
With the use of pulse width modulation technology, the inverter power supply produces welding currents and by use of switch power inverter technology, the dimensions and weight of the transformer is reduced, increasing efficiency by thirty percent.
This cutter is suitable for use in home DIY jobs and small projects.


Cons

The inverter plasma cutter is not fitted with a circuit breaker and, therefore, one needs to purchase one separately to prevent power outage problems that could result in the breakdown of the machine, destructing its normal operation.



Pros review

What we like

This cutting machine possesses features that are very beneficial to the operators. They make the plasma cutter a preference over other cutters. They include:

The cutter produces very quality and clean cuts with minimal distortion of the workpiece.
The cutter is very portable and is suitable for use in home DIY projects and light duty small projects.
This machine is suitable for use in industrial, construction and home environments.
The machine is easy to use and maintain and can be used by both experienced operators and first-time
The machine comes with a manufacturer’s warranty that ensures maintenance of the cutter.
Cons Review

What we don’t like

The cutter is at risk of destruction due to electric problems because it does not have circuit breakers fitted.



Customer Reviews

The cutter has received numerous positive reviews for its good performance. The customers were specifically very excited by the quality clean and smooth cuts from this machine. Its simplicity to operate makes its very suitable for use by novice users.

Most users were thrilled about the durability of the plasma cutter and its ability to cut through thick metals without distortion. The machine can be used for cutting different type of metals ranging from mild steel, aluminum and copper.

Conclusion

To get clean, smooth and high-quality cuts requires investing in the best quality cutter. For these qualities, the plasma cutter is a perfect choice. It is very light in weight and therefore you can use for longer without feeling overly fatigued.

This machine gives the opportunity to cut through different type of materials and, therefore, is very flexible and reliable to use. If you need to acquire a metal cutter, this machine should be your first choice. It guarantees quality and value for your money.

MOS DC inverter TIG welder

MOS DC inverter TIG welder

Specifications

1,Energy Conservation.
2,Safety
3,High efficiency
4,Stability

FEATURES:

1.Apply MOSFET switching power supply and PWM technology,energy-efficient and low noise. 2.HF start circuit ensure high success rate in arc striking. 3.Post-flow setting provides optimum shielding based on welding amperage without waste. 4.Automatic over-voltage and over-current protection as well as high temperature shutdown  function. 5.Smooth arc and stable welding performance;ideal for welding mild steel,copper and titanium, etc. 6.Rugged package and compact design makes it easy to take TIG welding capability where it's  needed. 7.Supplied complete with TIG torch,earth clamp,welding cable,face mask and welding brush. 1.high working frequency, high efficiency, no noise. 2.Compact and portable. 3.High frequency and high voltage arc initiating, high success rate. 4.With the perfect protect automatic functions of over pressure, over load and lack of pressure. Safty and reliable. 5.Applicable to wide range of power supply voltage,best for project site working. 6.Used widely for welding carbon steel, stainless steel, alloy steel and other non-ferrous metals. 7.Most suitable for welding of stainless steel products, decoration industry, precision welding, light gage welding and others. 8.Small current can stably start small splash, no-load loss is low. 9.perfect self-protection ability for onvervoltage, undervoltage, overcurrent etc.. 10.small curent can stabilizie arc, little spater and low no-load lossed with arc stability.

1. DC TIG and MMA , dual purposes, providing added value   portable welder

2. HF arc starting, easy to operateProtective devices against over-heat, over-current and over-voltage 

3. Unique output special design can suit wire filling welding and form good-looking welding seam. 

4 Compact structure,excellent welding performance, reliable and durable, easy to maintain

5  Suitable for all kinds of acid and alkaline welding rods

applications

widely utilized in a plenty of vital industries, such as architecture, bridge construction, steel structures, underground mines,thermal power plants, pressure vessels, automobile making, shipbuilding and metal processing .

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Metal Inert Gas (MIG) welding

Metal Inert Gas (MIG) welding, also sometimes called Gas Metal Arc Welding (GMAW) is a process that was developed in the 1940s for welding aluminum and other non-ferrous metals. MIG welding is an automatic or semi-automatic process in which a wire connected to a source of direct current acts as an electrode to join two pieces of metal as it is continuously passed through a welding gun. A flow of an inert gas, originally argon, is also passed through the welding gun at the same time as the wire electrode. This inert gas acts as a shield, keeping airborne contaminants away from the weld zone.

The primary advantage of MIG welding is that it allows metal to be welded much more quickly than traditional "stick welding" techniques. This makes it ideal for welding softer metals such as aluminum. When this method was first developed, the cost of the inert gas made the process too expensive for welding steel. Over the years, the process has evolved, however, and semi-inert gases such as carbon dioxide can now be used to provide the shielding function, which now makes MIG welding cost-effective for welding steel.


Besides providing the capability to weld non-ferrous metals, MIG welding has other advantages:

It produces long, continuous welds much faster than traditional welding methods.
Since the shielding gas protects the welding arc, this type of welding produces a clean weld with very little splatter.
It can be used with a wide variety of metals and alloys.
The primary disadvantages of MIG welding include the following:

The equipment is quite complex, as MIG welding requires a source of direct current, a constant source and flow of gas, as well as the continuously moving wire electrode. Plus, electrodes are available in a wide range of sizes and are made from a number of metal types to match the welding application.
The actual technique used is different from traditional welding practices, so there is learning curve associated with MIG welding, even for experienced welders. For example, MIG welders may need to push the welding puddle away from them and along the seam.
The necessity for the inert gas shield means that MIG welding cannot be used in an open area where the wind would blow away the gas shield, unless other precautions are taken to prevent this.
Since its development in the middle of the 20th century, MIG welding has become commonplace in many manufacturing operations. For example, it is commonly used in the automobile industry because of its ability to produce clean welds, and the fact that it welds metals quickly.

IGBT Inverter dc arc Welding Machine

The main features of IGBT Inverter dc arc Welding Machine 

-Compactable,portable,high efficiency and energy saving. 

-Anti static, thermostatic, fan cooled. 

-Easy arc starting, stable arc welding, deep weld pool and good welding appearance. 

-Adjustable hot striking arc current. 

-Suitable for various acidic , alkaline Welding rods.

-Especially suitable for welding the carbon steel, stainless steel, low alloy steel and other metals. 

MOS inverter air plasma welding machine

DC inverter welding machine, electric arc welding machine

 DC inverter welding machine, electric arc welding machine

Features:

Mini, lightweight, high quality and energy-saving.

Excellent arc–starting and arc force, it can resist disturbing stable arc and little spatter.

High quality welding, deep bath and strong strength.

Auto protection of over-voltage and over-current.

Be able to work continuously. It can balance automatic when voltage is waving.

Suitable for welding all kinds of basic welding rods.

Anti-Stick, Hot start, ARC force.

1.Minimizing,lightness,high quality and energy-saving
2.Good arc-starting and arc force, it can be resist disturb stable arc and little spatter
3.High welding quality,deep bath and strong strength
4.Auto protection of over-voltage and over-current
5.Be able to work continuously, it can balan automatic when voltage is waving
6.Suit for welding all kind of basic welding rod
7Be able to weld cellulose rod

ZUOERD DC inverter ARC welder

ZUOERD DC inverter ARC welder

Types of Arc Welder DC inverter ARC welder

Types of Arc Welder

Arc welding has been around for a long time, and there are now a number of distinct types of arc welder. This page discusses the pros, cons and typical characteristics of these different types of welder.

DC inverters

Unlike traditional arc welders, modern DC inverter arc welders are very small, light and portable. Even the cheap ones available from as little as £100 function well, though the more expensive ones (up to £500) will be much more robust and will normally last much longer.

Pros:

• Very efficient - they can run up to about 140 amps on a 13 amp 240V supply, and tend to have have good duty cycles (you can weld for longer on higher settings).
• Small, lightweight and very portable. Generally less than 10kg in weight.
• DC output results in easy arc starting
• Most inverters have features such as hot starting to improve the ease of starting, and a soft finish to reduce the crater at the end of a weld.
• All but the cheapest have 70V or 80V OCV (open circuit voltage)
• Most can be used for scratch start TIG. More expensive ones tend to have HF (high frequency) start functions for TIG welding.
• Pricier ones have features such as "arc force" which adjusts the voltage on the fly to cope with dirty plate.

Cons:

• Inverter machines are complex electronically, and repairs can be very expensive. The cheaper ones are sensitive to knocks and spikes in input voltage. The more expensive ones have more protection - some are designed to withstand being dropped from 0.5m.

Verdict:

DC inverters are the sensible buy for anyone new to arc welding. Even the cheapest ones tend to weld very nicely, the downside of the cheap ones being that cheap components that don't last very well.

AC/DC inverters

These are normally aimed at TIG welding, and would not be bought for arc welding alone, but they generally have arc welding settings.

Pros:

• Some rods are AC only. An AC/DC inverter can be used with these.
• AC is not susceptible to magnetism which can cause stray arcs on DC machines.
• The TIG welding capabilities.

Cons:

• Expense: For inverter welders the AC function takes a lot of electronics, so prices of half reasonable machines start at £1000.

Verdict:

Fantastic for ARC welding, but only buy one if you also need to TIG aluminium.

DC transformer welders

Transformer based arc welders are normally very heavy, and are aimed at TIG welding in a workshop rather than portability.

Pros:

• These are excellent quality welders - for ease of use they are only bettered by decent inverter welders.
• Duty cycles tend to be higher than modern inverter welders, so these machines are still used by fabrication companies when they need to do long runs of weld at very high amps.
• Can last for much longer than inverter based machines, and are easier and cheaper to repair if they do go wrong. Many are still in regular use after 30 years.
• The TIG welding capabilities.

Cons:

• Not Portable: A Syncrowave 300 weighs 330kg and is the size of a house.
• The machines with huge power requirements - the Syncrowave manual recommends a 110 amp 240V supply.
• The buzz from the enormous transformers and 2 foot diameter fans create a lot of noise.
• Parts available for the older ones is becoming sketchy.

Verdict:

Buy one secondhand if you want something that will last and have the space to keep it.

AC oil cooled welders

Pros:

• Very simple heavily built welders that should last for ever.
• Normally have both 50V and 80V settings. Smooth consistent arc while welding.
• Oil cooling results in an excellent duty cycle.
• It is possible to pick them up cheaply secondhand.

Cons:

• Not Portable: Oil cooled welders are very heavy, even small units can weigh in excess of 100kg.
• Starting the arc in AC is more difficult than with DC welders.
• Can't be used for TIG welding.

Verdict:

Old school equipment that you should never need to replace. Buy one second hand if you are old school, but bear in mind they take a little more skill to use.

AC air cooled welders

Often referred to as buzz boxes. A number of companies made reasonable quality air cooled AC welders in the past. The technology is now the reserve of DIY stores selling welders to people who don't know any better. They are the least usable of any type of arc welder.

Pros:

• Cheap! Most large DIY stores will sell them for as little as £50.

Cons:

• They tend to have a low OCV (open circuit voltage), so starting an arc is tricky.
• The low OCV results in an unstable arc, and this gets worse as the transformer heats up. While they will weld it is to a lower standard than any of the other types of ARC welder.
• Can't be used for special rods that require over 70V OCV (such as low hydrogen).
• Very poor duty cycle: Many of the cheap ones will weld for only 30 seconds before needing a rest for 10 minutes on the maximum amp setting.
• They are less efficient than inverter welders and will tend to require a dedicated supply to work on higher settings.
• Can't be used for TIG welding.

Verdict:

To a great extent these are a waste of money. They are the most difficult to use of any arc welder, so most DIY buyers will decide they don't like the process and give up. The duty cycles are annoyingly low. They are only really suitable for someone who wants an arc welder for very occasional use and doesn't want to spend money.