Welding and Cutting

Oxygen and acetylene are commonly used for welding because they create a high-temperature flame that can melt and join metals together effectively. The mixture of oxygen and acetylene provides a clean and precise flame, making it suitable for various welding applications. Additionally, the high heat produced by the oxy-acetylene flame allows for efficient welding of thick metal sections.

Electrons flowing across an air gap produce an arc. The resistance built up that is needed to push these electrons across the gap produces the heat. This same resistance causes the electrodes to get hot.

The flux coating on a welding rod provides a gas shield to protect the molten metal during the welding process. The flux melts and releases gas to shield the weld pool from atmospheric contamination.

Mixing Acetylene and Oxygen in the correct proportions produces an extremely hot flame. Using just enough Oxygen so that the Acetylene is almost completely consumed in the flame is called a Neutral Flame. In most welding and cutting applications you would utilize this flame. Reducing the amount of Oxygen produces a Carburizing Flame. It is yellowish and not as hot as a Neutral Flame, but, is used in certain situations. Welding Aluminum is one. Increasing the Oxygen produces an Oxidizing Flame. It produces a flame that is pointed, colder, and louder than a Neutral Flame. It wastes fuel and isn't as efficient as a Neutral Flame.

If your question is "Why is Acetylene and Oxygen used for welding/cutting NOT Oxygen and air"? This is why. Acetylene and air mixed in correct proportions produces a flame temperature of 4500F to 4800F degrees. Acetylene mixed with Oxygen in the correct proportions produces a flame well above 5500F degrees. This extra heat melts the metal faster and increases the speed you can cut or weld. Other gasses instead of Acetylene are used but do not produce as high a temperature. Oxygen is almost always used with these other gasses.

Some common compressed gases used for welding include acetylene, argon, carbon dioxide, and helium. These gases are often used in various combinations depending on the welding process and materials being joined.

You have to clean the beak of the soldering iron with a sandpaper before pressing the tip of the welder on the wire. Heat it up (the wire) first, by pressing the tip of the welder on it) and only afterwards place the tin on the wire. [This answer pertains to soldering not welding.] In the welding process incomplete fusion occurs when the weld does not fuse with the base metal and can be caused by #1 travel speed too slow which allows the weld to roll over the edges trapping slag between the weld and the base metal. #2 amperage set too low which doesn't allow complete melting of the base metal, the weld deposit, and/or the flux/coating/slag. #3 electrode angle wrong which pushes the weld metal over the slag. #4 amperage setting too high and/or travel speed too fast which undercuts the edge of the base metal allowing slag to be trapped there and subsequent passes to bury the slag. #5 incorrectly placing the beads in multiple passes leaving voids along the edges that subsequent passes do not penetrate and remove. #6 arc length too long allowing weld to be deposited randomly. These answers relate to SMAW (stick welding) but some can be addressed in other processes. Other factors may apply to this problem in any of the welding processes. If you are reffering to a different process please ask again and specify which process.

It's called a Neutral flame. Enough Oxygen is added to the fuel to allow almost complete combustion. The remaing fuel is combined with the surrounding air and burned. This is the best flame for most cutting and welding operations. Too little Oxygen produces a Carburizing flame. It is yellow and produces smoke. A slightly Carburizing flame is used when welding Aluminum.

Too much Oxygen produces an Oxidizing flame. It begins to sound louder and the inner flame comes to a point.

In TIG (tungsten inert gas) welding, the flame is created by the flow of inert gas (such as argon) through the torch. The gas creates a protective atmosphere around the weld area, preventing oxidation and allowing for a clean, precise weld. The tungsten electrode is used to create an arc that generates the heat needed to melt the metals being welded.

Depends on the type of material to be welded, the size of the flame, and in my situation slowly deteriorating eyesight. Basically shade 4 or 5 will be adequate. As dark as 6 on aluminum. You will be able to tell if you aren't using a dark enough shade as you can get a "flash" ( Like a sunburn on the eyes). Start with a #5 and go from there.

Flux is used to protect the weld from the atmosphere. Flux produces a gas shield over the liquid portion of the weld during the welding process as the electrode is used. The flux then forms a protective layer over the weld called slag. Flux also acts as a deoxidizer, pulling oxygen and nitrogen from the weld pool to the surface, preventing porosity. There are many other and much more technical reasons that involve chemistry of the weld metal, arc characteristics, and mechanical properties of the finished weld.

Fusion welding joins materials by melting them together, while non-fusion welding joins materials without melting them. Fusion welding includes processes like MIG, TIG, and arc welding, where a filler material may be added. Non-fusion welding methods, such as friction welding or ultrasonic welding, rely on pressure or friction to create the bond between materials.

Fusion is the melting and mixture of base metal to the melted filler material (Rod or Electrode). It takes place in the puddle and is the Weld. Sorta like making mud by adding water to dirt. If they don't mix there is no mud.

not it can always be changed back to its original shape. but if you burn metal which i dont consider doing it is a chemical change. like melting butter and burning butter. burning is chemical, melting can be cooled again into its original form.

The joining of magnesium alloys by torch welding or brazing is possible without a fire hazard because the melting point of magnesium is 1202*F to 858*F below its boiling point, where magnesium may start to burn.

Oxyhydrogen flame is used for welding because it burns very hot, reaching temperatures up to 2800°C, which is needed for melting and fusing metal together. It also leaves a clean and precise weld, making it suitable for delicate welding applications. Additionally, oxyhydrogen produces a reducing atmosphere that helps prevent oxidation of the metal during the welding process.

two reasons i can think of:

1 - Probably dont need to, usually welding material of constant thickness.

2 - The transformer is mechanically adjusted on most welders, this means that that there would be a possibility for electricity jumping in the transformer, and premature failure, or fire.

Common gases used for welding include argon, helium, and carbon dioxide. These gases are often used as shielding gases to protect the weld area from atmospheric contamination and to help improve the quality of the weld. Oxygen and acetylene are also commonly used in oxy-fuel welding and cutting processes.

Slag in welding acts as a protective layer on the molten weld pool. It helps to prevent contamination from the atmosphere, improve the weld's appearance, and facilitate the solidification process of the weld metal.

No, lack of penetration and lack of fusion are two different welding defects. Lack of penetration occurs when the weld metal does not extend fully into the joint, resulting in an incomplete weld. Lack of fusion, on the other hand, occurs when the weld metal does not fuse completely with the base metal or the previous weld pass.

The melting point of stainless steel welding filler rod can vary depending on the specific grade of stainless steel being used. Typically, stainless steel filler rods have a melting point ranging from 2,500 to 2,800 degrees Fahrenheit. It is important to refer to the manufacturer's specifications for the exact melting point of the specific stainless steel filler rod being used.

The temperature of an arc welding process can reach up to 6,500 degrees Fahrenheit (3,600 degrees Celsius). This high temperature is necessary to melt the base metals and the filler material, allowing them to fuse together. Heat control is crucial in arc welding to achieve proper penetration and weld quality.

Yes, welding rods are generally magnetic because they often contain iron and steel elements. However, the magnetic properties may vary depending on the specific composition and coating of the welding rod.

Welding uranium requires special expertise and precautions due to its radioactive properties. It is typically done using a process known as electron beam welding, which minimizes the heat-affected zone and the risk of contamination. Strict safety measures must be followed to protect the welder and prevent the spread of radioactive particles.

The sparks generated during welding are called welding sparks. They are tiny fragments of molten metal that separate from the welding material or workpiece due to the intense heat generated during the welding process.