Lincoln equipment for wire welding includes all Ranger® and all Vantage® models. Other Lincoln equipment can be upgraded to provide this capability: Pipeliner™ 200 D, all Classic® models and SAE-400.
Engine-driven welders are generally used when electric power is not available for arc welding. Usually these are outdoor applications. However, engine-drive welders are often used for indoor applications when it is not convenient to supply power to electric "plug-in" arc welders. These indoor situations include everything from minor repair jobs to major plant shutdowns. When operating engine-driven welders indoors, vent the exhaust outside if at all possible, or use in large spaces with good ventilation.
The basic considerations when choosing an engine-driven welder are:
- Application
- Engine Type
- Portability
- AC Generator Power
For AC TIG welding the Lincoln Ranger™ 10,000 and 3 Phase have an AC weld output to which an optional TIG Module can be attached. Although the Ranger™ 305 G (shown) & D and Vantage products do not have an AC weld output, a Precision TIG® 225 or an Invertec® V205-T AC/DC inverter can be connected for AC TIG welding.
Application
In trying to select an engine drive, the first thing to consider is the application. Ask yourself these questions:
1. Is this new construction or a repair job? Also, what is the size of the project?
2. Is there a particular welding process you would like to use? You may want to stick with a process with which you feel most comfortable, or there may be a certain process required on the job.
3. Is this a pipe welding project? The equipment chosen needs to produce an arc suitable for this type of work.
4. Will the job require arc gouging? Arc gouging is repair work usually done in industrial jobs.
5. What type of material needs to be welded? Most of the time the material will be a common mild steel plate. However, if it's aluminum, the welding will require different equipment.
Using this information, match it to the welding processes described below:
Process Descriptions
Stick Welding - CC (constant current) stick welding is the most common choice for field work. Electrode (welding rod) diameters most commonly used are 3/32", 1/8" and 5/32". The simplest equipment will handle a wide variety of construction and repair applications. Output is measured in amps, and up to 200 amps is sufficient for the electrode sizes mentioned. Most equipment is DC (direct current) output for best arc stability. A 200-amp welder is usually able to get the job done.
Pipe Welding - Pipe welding is most often done with stick electrodes. Look for equipment which specifies it will pipe weld, meaning that suitable arc characteristics are specifically provided for this process. Electrode diameters are typically 5/32" and 3/16", and 200 amps is sufficient for this process.
Arc Gouging - Arc Gouging is a process for removing metal. It is most commonly done in the stick mode. An arc is used with a carbon rod to melt metal and compressed air blows the molten metal away. Gouging is used to remove bad welds and to repair cracks. Most operators use equipment with 400 to 600 amps for higher productivity with 5/16" or 3/8" diameter carbon rods. However, smaller rods can be used with lower amperage. For example, a 5/32" carbon rod can be used with 150 amps. Usually a separate compressor supplies the air. A few engine-driven welders are manufactured with built-in compressors.
Wire Welding - CV (constant voltage) wire welding requires a wire feeder. Wire welding's main benefit is greater productivity: more weld metal can be deposited than for stick during the same amount of time. Although wire welding is much less common compared to the above processes, the application is growing. The engine-driven welder must have a CV-wire capability. Since most engine-driven welder work is outdoors, self-shielded flux-cored wire (which requires no shielding gas) is highly recommended to keep the process simple. When welding under windy conditions, the shielding gas associated with gas-shielded processes (solid wire or gas-shielded flux-cored wire) may be blown away, resulting in poor quality welds. Output is measured in Volts and Amps. Wire diameters are typically .035" and .045", although 5/64" is often used for higher productivity. A welder with 30 volts and 300 amps is usually sufficient for many applications up to 5/64" wire.
TIG Welding - a slower, but more precise type of welding well-suited for thin materials and unusual alloys. A TIG torch and shielding gas are required. If welding on aluminum, an AC weld output is required from the engine-driven welder and a high-frequency generator is attached to start and sustain the arc. Or, an AC TIG welder can often be powered from the engine-driven welder's AC generator, if at least 8,000 watts is available. Most TIG welding is done below 100 amps.
Plasma Cutting - a metal cutting process which utilizes an arc and compressed air. The engine-driven welder's AC generator can often supply power to a plasma cutter. At least 8,000 watts of power is recommended.
The Lincoln Vantage 500 and SAE 400 will gouge up to 3/8" carbons with a separate compressor. An Air Vantage™ 500 has a built-in compressor.
Engine Type
After the application has been defined and the welding process has been selected, the next step is to choose the engine. Diesel, gasoline or liquid propane gas (LPG) are the choices. A diesel engine offers better fuel economy than a gasoline engine, and diesel fuel does not ignite as easily as gasoline. Refineries almost always require diesel-fueled machines rather than gasoline-fueled machines. Another consideration for large jobs is whether the fuel is being supplied at the job site. If so, it is usually diesel, but whatever the fuel, the cost savings will usually determine the engine choice.
Gasoline engines are sometimes preferred in cold weather climates because they start more easily without extra starting aids, such as ether start kits and winterized fuel for colder weather.
LPG is much less common, but becomes an important alternative choice when diesel and gasoline exhaust emissions are not permitted for indoor applications.
A spark arrester may also be required in forest and oil service areas.
Portability
For pipe welding Lincoln engine-driven welders include the Ranger™ 250, 305 G & D, Pipeliner® 200 D (shown), all Classic™ and Vantage machines, and SAE-400.
Sometimes the need for portability will be the main factor in equipment selection. If an engine-driven welder needs to be carried or lifted to a work area, having a small gasoline stick welder will normally be the best answer.
AC Generator Power
AC power is sometimes required on the jobsite for grinding welds or for lights when working at night. Normally, 3,000 watts of AC generator power is plenty of power for these applications. Ground Fault Circuit Interrupters (GFCIs) are recommended and may be required. An AC TIG welder or plasma cutter will require more power - typically 8,000 watts minimum.
Additional Help
Product literature published by welding equipment manufacturers provides additional information that cannot be covered here in detail. Company sales representatives and the customer service departments are also excellent sources of information for technical questions on applications and products.
Click Here for details on Lincoln Engine Driven Welder / Generators
http://www.lincolnelectric.com/knowledge/articles/content/enginedrive.asp
Rabu, 10 September 2008
Selasa, 09 September 2008
Tips on Handling Welding Rods
Welding rods get no respect. Out in the field I've seen guys throwing 50lb. rod cans from the truck onto the ground, torching cans open diagonally, beating the wrong end open with a chipping hammer and every other conceivable tool, and leaving open rod cans out in the open.
Let's look at what's wrong with each…
First and foremost, ALWAYS open the "right" end of the can. Some cans and boxes even say "open other end", or "don't open this end", or "the other end moron!." (last one made up by me.) The reason you need to open the right end is because you can damage the flux coating. You want to open it on the side where the rod is bare for the stinger, or electrode holder. There's a lot less chance of damaging the flux that way. 7018 is very prone to flux damage while 6010 is a lot tougher.
Most guys out in the field aren't gonna' be thinking about the welding rods inside the can as they toss them from the truck to the ground. When the cans get manhandled the flux gets jarred loose on the welding rods inside. It's bad enough when the flux gets chipped off the end of the rod, flux chipped from the middle and you can pretty much kiss that rod goodbye. It's worse, if you don't realize it's chipped because right in the middle of a good weld you'll suddenly be welding with no flux. No flux equals no shielding from the atmosphere, and that equals a garbage weld.
You can use a lot of different ways to open rod cans out in the field if you are careful. I've even used the P38 C ration can opener I had in the army.If you use an oxygen/acetylene torch you need to be real careful not to burn the flux on the rods inside.
You can open a rod can with a chipping hammer, but it's not advisable. You gotta' be sure and hit it just right, at the edge of the can. You should hit the edge with the hammer follow-through swinging away from the can, not striking down into the can at the top. (I'm sure the electrode manufacturers are cringing when they read this!)
Of course the best way is whatever the can is designed for, some of them open like a sardine can, but a lot of times it doesn't work so you gotta' improvise.
Leaving open cans out allows moisture to get into the flux. Moisture in the flux can cause porosity, or worm holes in the weld. Rods should be stored in a proper oven or unheated container if they don't need the moisture protection. 7018 needs an oven, while 6010 doesn't need the heat, but still needs to be kept protected.
http://www.rodovens.com/welding_articles/welding-rods.htm
Let's look at what's wrong with each…
First and foremost, ALWAYS open the "right" end of the can. Some cans and boxes even say "open other end", or "don't open this end", or "the other end moron!." (last one made up by me.) The reason you need to open the right end is because you can damage the flux coating. You want to open it on the side where the rod is bare for the stinger, or electrode holder. There's a lot less chance of damaging the flux that way. 7018 is very prone to flux damage while 6010 is a lot tougher.
Most guys out in the field aren't gonna' be thinking about the welding rods inside the can as they toss them from the truck to the ground. When the cans get manhandled the flux gets jarred loose on the welding rods inside. It's bad enough when the flux gets chipped off the end of the rod, flux chipped from the middle and you can pretty much kiss that rod goodbye. It's worse, if you don't realize it's chipped because right in the middle of a good weld you'll suddenly be welding with no flux. No flux equals no shielding from the atmosphere, and that equals a garbage weld.
You can use a lot of different ways to open rod cans out in the field if you are careful. I've even used the P38 C ration can opener I had in the army.If you use an oxygen/acetylene torch you need to be real careful not to burn the flux on the rods inside.
You can open a rod can with a chipping hammer, but it's not advisable. You gotta' be sure and hit it just right, at the edge of the can. You should hit the edge with the hammer follow-through swinging away from the can, not striking down into the can at the top. (I'm sure the electrode manufacturers are cringing when they read this!)
Of course the best way is whatever the can is designed for, some of them open like a sardine can, but a lot of times it doesn't work so you gotta' improvise.
Leaving open cans out allows moisture to get into the flux. Moisture in the flux can cause porosity, or worm holes in the weld. Rods should be stored in a proper oven or unheated container if they don't need the moisture protection. 7018 needs an oven, while 6010 doesn't need the heat, but still needs to be kept protected.
http://www.rodovens.com/welding_articles/welding-rods.htm
Senin, 08 September 2008
Storage Tanks and Process Tanks
Storage tanks and process tanks are general purpose industrial containers. Storage tanks and process tanks can have many configurations depending upon dimensions, orientation, placement, and wall configuration. Materials of construction will dictate the application that is suitable for the tank. Storage tanks and process tanks are used in a number of applications including short term storage, long term storage, mixing, blending, metering and dispensing.
The most important parameters to consider when specifying storage tanks and process tanks are their capacity and dimensions. The capacity of the storage tank or process tank is the internal volume available for the storage of materials. The diameter of the tank is typically expressed in feet units. The length of the tank is measured in feet. The orientation of the tank can be vertical or horizontal. Vertical tanks stand vertically and typically have access ports on the bottom. Horizontal tanks are often mounted on stands or saddles and can have access ports on the bottom or top. The placement of tanks is typically either above ground or underground, depending on the construction. Portable tanks can be moved from one place to another, via wheels or other moving device. The wall construction of the tank may dictate the application that the tank is suitable for. Single wall tanks are common for various applications. Double wall tanks are used in applications where higher-pressure considerations are necessary.
Materials of construction for storage tanks and process tanks include fiberglass FRP, galvanized steel, plastic, stainless steel, steel, and titanium. Fiberglass reinforced polyester (FRP) is made of a series of long glass fibers embedded in a resin. It can be formed into almost any shape before curing. Once cured it is light in weight, very strong material that has excellent corrosion resistant properties. In some cases, fiberglass is used along with the plastic in the body material of the tank. Galvanized steel is cold rolled steel that has been surface treated with a layer of zinc. Stainless steel is a type of metal that resists corrosion. Steel is a ferrous-based metal having a variety of physical properties depending on composition. Steel used in tank applications is typically rolled sheet steel. Titanium is a lightweight, very strong metal used in applications where there are temperature extremes or extraordinary stresses. Storage tanks and process tanks with special linings are constructed of special materials for corrosive or other special processes. Considerations might also include glass lined or special coatings.
Common industries and applications that use storage tanks and process tanks include chemical processing, cosmetics processing, food and beverage processing, oil and fuel processing, paper and pulp processing, pharmaceutical processing, plastic processing, power generation and energy processing, and water applications.
The most important parameters to consider when specifying storage tanks and process tanks are their capacity and dimensions. The capacity of the storage tank or process tank is the internal volume available for the storage of materials. The diameter of the tank is typically expressed in feet units. The length of the tank is measured in feet. The orientation of the tank can be vertical or horizontal. Vertical tanks stand vertically and typically have access ports on the bottom. Horizontal tanks are often mounted on stands or saddles and can have access ports on the bottom or top. The placement of tanks is typically either above ground or underground, depending on the construction. Portable tanks can be moved from one place to another, via wheels or other moving device. The wall construction of the tank may dictate the application that the tank is suitable for. Single wall tanks are common for various applications. Double wall tanks are used in applications where higher-pressure considerations are necessary.
Materials of construction for storage tanks and process tanks include fiberglass FRP, galvanized steel, plastic, stainless steel, steel, and titanium. Fiberglass reinforced polyester (FRP) is made of a series of long glass fibers embedded in a resin. It can be formed into almost any shape before curing. Once cured it is light in weight, very strong material that has excellent corrosion resistant properties. In some cases, fiberglass is used along with the plastic in the body material of the tank. Galvanized steel is cold rolled steel that has been surface treated with a layer of zinc. Stainless steel is a type of metal that resists corrosion. Steel is a ferrous-based metal having a variety of physical properties depending on composition. Steel used in tank applications is typically rolled sheet steel. Titanium is a lightweight, very strong metal used in applications where there are temperature extremes or extraordinary stresses. Storage tanks and process tanks with special linings are constructed of special materials for corrosive or other special processes. Considerations might also include glass lined or special coatings.
Common industries and applications that use storage tanks and process tanks include chemical processing, cosmetics processing, food and beverage processing, oil and fuel processing, paper and pulp processing, pharmaceutical processing, plastic processing, power generation and energy processing, and water applications.
Sabtu, 06 September 2008
How Fire Extinguishers Work
Q: When is a water extinguisher dangerous?
A: A water extinguisher can put out things like burning wood, paper or cardboard, but it doesn't work well on electrical fires or fires involving inflammable liquids. In an electrical fire, the water may conduct the current, which can electrocute you.
A fire extinguisher is an absolute necessity in any home or office. While there's a good chance that the extinguisher will sit on the wall for years, collecting dust, it could end up saving your property and even your life.
In this article, we'll see exactly what fire extinguishers do and how they do it. We'll also find out what causes fire in the first place, learn the correct way to use an extinguisher and see what sort of fire suppressant works best on different types of fires.
What is Fire?
Extinguishing a Fire
We don't usually think much about how a fire extinguisher works -- until we need to use one.
Fire is the result of a chemical combustion reaction, typically a reaction between oxygen in the atmosphere and some sort of fuel (wood or gasoline, for example). Of course, wood and gasoline don't spontaneously catch on fire just because they're surrounded by oxygen. For the combustion reaction to take place, the fuel has to be heated to its ignition temperature.
Here's the sequence of events in a typical wood fire:
- Something heats the wood to very high temperatures. This could be any number of things -- focused light, friction, something else that is already burning.
- When the wood reaches about 500 degrees Fahrenheit (260 degrees Celsius), the heat decomposes some of the cellulose material that makes up the wood.
- Decomposed material is released as volatile gases, typically a compound of hydrogen, carbon and oxygen.
- When the gas is hot enough, the compound molecules break apart, and the atoms recombine with the oxygen to form water, carbon dioxide and other products.
- The gases, which rise through the air, make up the flame. Carbon atoms rising in the flame emit light as they heat up. (Check out How Light Bulbs Work to find out why heated objects emit light.)
- The heat of the flame keeps the fuel at the ignition temperature, so it continues to burn as long as there is fuel and oxygen.
As you can see, there are three essential elements involved in this process:
- Extreme heat
- Oxygen (or similar gas)
- Fuel
Fire extinguishers are designed to remove at least one of these elements so that a fire will die out. There are several different ways of doing this, as we'll see in the next section.
http://home.howstuffworks.com/fire-extinguisher.htm
A: A water extinguisher can put out things like burning wood, paper or cardboard, but it doesn't work well on electrical fires or fires involving inflammable liquids. In an electrical fire, the water may conduct the current, which can electrocute you.
A fire extinguisher is an absolute necessity in any home or office. While there's a good chance that the extinguisher will sit on the wall for years, collecting dust, it could end up saving your property and even your life.
In this article, we'll see exactly what fire extinguishers do and how they do it. We'll also find out what causes fire in the first place, learn the correct way to use an extinguisher and see what sort of fire suppressant works best on different types of fires.
What is Fire?
Extinguishing a Fire
We don't usually think much about how a fire extinguisher works -- until we need to use one.
Fire is the result of a chemical combustion reaction, typically a reaction between oxygen in the atmosphere and some sort of fuel (wood or gasoline, for example). Of course, wood and gasoline don't spontaneously catch on fire just because they're surrounded by oxygen. For the combustion reaction to take place, the fuel has to be heated to its ignition temperature.
Here's the sequence of events in a typical wood fire:
- Something heats the wood to very high temperatures. This could be any number of things -- focused light, friction, something else that is already burning.
- When the wood reaches about 500 degrees Fahrenheit (260 degrees Celsius), the heat decomposes some of the cellulose material that makes up the wood.
- Decomposed material is released as volatile gases, typically a compound of hydrogen, carbon and oxygen.
- When the gas is hot enough, the compound molecules break apart, and the atoms recombine with the oxygen to form water, carbon dioxide and other products.
- The gases, which rise through the air, make up the flame. Carbon atoms rising in the flame emit light as they heat up. (Check out How Light Bulbs Work to find out why heated objects emit light.)
- The heat of the flame keeps the fuel at the ignition temperature, so it continues to burn as long as there is fuel and oxygen.
As you can see, there are three essential elements involved in this process:
- Extreme heat
- Oxygen (or similar gas)
- Fuel
Fire extinguishers are designed to remove at least one of these elements so that a fire will die out. There are several different ways of doing this, as we'll see in the next section.
http://home.howstuffworks.com/fire-extinguisher.htm
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