Welding and Cutting

Oxygen is used in welding to increase the burn rate of the fuel gas, such as acetylene, in the oxy-fuel welding process. The oxygen reacts with the fuel gas, creating a high-temperature flame that is used to melt and join metal together. Additionally, oxygen is used in oxy-fuel cutting to aid in the combustion process, resulting in a clean cut through metal.

Resistance spot welding typically occurs at temperatures between 1,800 and 2,500 degrees Celsius at the welding point. The high temperature is generated due to the electrical resistance between the workpieces, causing them to melt and fuse together.

Acetylene torches can be used to weld metals together because they have a higher temperature than the metal's melting point.

The most common gas used in welding is a mixture of argon and carbon dioxide, known as shielding gas. This gas helps protect the weld pool from contaminants in the air and stabilizes the arc during the welding process.

Fusion in welding refers to the process of melting and combining two or more metal pieces to create a solid bond. This is achieved by heating the metal pieces to their melting point, allowing them to fuse together upon cooling. Fusion welding techniques include processes such as arc welding, TIG welding, MIG welding, and oxy-fuel welding.

To convert inches to meters, divide by 39.37 since 1 inch is equal to 0.0254 meters. Thus, a 25-inch welding rod is approximately 0.635 meters long.

n - Oxygen and Acetylene are the original gasses that are used for welding/cutting. Newer mixtures are slowly replacing Acetylene as a fuel. These gasses don't always reach the temperatures attained by Acetylene. Us old-timers still prefer Acetylene.

When aluminium reacts with iron oxide, a thermite reaction occurs, producing aluminum oxide, iron, and a large amount of heat. This reaction is used in welding and metal cutting applications due to the intense heat generated.

When the correct amount of Oxygen is mixed with the Acetylene a NEUTRAL flame is produced. Less than that amount produces a CARBURIZING flame. Too much Oxygen creates an OXIDIZING flame. Most welding/cutting is done with a NEUTRAL flame but all flame adjustments have their purpose.

The word FLUX means to clean. In the SMAW (stick welding) process it is the coating and does this by scrubbing the molten metal to remove impurities and floats them to the top and out of the puddle. It creates a slag to protect the puddle from contamination from the atmosphere while the weld cools. It slows the rate of cooling which tempers the weld. It adds alloys to the weld metal changing its characteristics such as hardness or malleability. It can also add metal to the puddle producing more weld per inch. It controls the amount of spatter produced. It determines what electrical current can be used. The thickness of the coating determines in what position ( flat, horizontal, vertical, overhead) the welds can be made. The thickness also insulates the electrode to help keep it from melting. Thicker coatings help direct the arc and keeps it from wandering. In the OFW (gas welding) process its main function is to clean.

The acid needed for aluminum welding is typically called aluminum flux or aluminum brazing flux. It helps to remove oxide layers from the surface of aluminum, allowing for better adhesion between the metal and the filler material during the welding process.

Argon is used in welding to prevent oxygen from entering the weld site. Oxygen is basicly bad for the weld and Argon displaces the oxygen which results in a better weld (less heat stress, less air pockets (imperfections in the weld) etc.)

Acetylene welding is a process that involves using acetylene gas as a fuel combined with oxygen to produce a high-temperature flame for joining metals together. The flame generated by burning acetylene with oxygen can reach temperatures up to 3,100 degrees Celsius, making it effective for welding tasks.

Arc welding involves using an electric arc to generate high heat to melt metal pieces and fuse them together. The melting point varies depending on the type of metal being welded, but generally, common metals like steel have melting points in the range of 2500-2800 degrees Fahrenheit. It is important for the welder to monitor and control the heat to ensure proper fusion of the metal.

The Indian Standard (IS) equivalent to the International Organization for Standardization (ISO) standard can be found by adding "IS" before the ISO number. For example, ISO 9001 is equivalent to IS 15700 in India.

Warpage or distortion in welding is typically caused by uneven heating and cooling of the welded material. When the material cools down after the welding process, areas that cool faster may contract at a different rate than others, leading to warping. Additionally, excessive heat input, improper welding technique, or welding on materials with residual stress can also contribute to warpage or distortion.

No, Acetylene is heavier than air. In fact for this reason most countries do not allow its use for welding in confined spaces.

Because in the past, leaking acetylene cylinders have filled up the bottom of the area to be welded, with explosive results.

Actually it is slightly lighter than air. Air is roughly 79% Nitrogen and 21% Oxygen. Both Oxygen and Nitrogen exist naturally as homo-nuclear diatomics N2 and O2. Nitrogen has a molecular weight of 28.0 amu(atomic mass unit). (14.0 amu x2) Oxygen has a molecular weight of 32.0 amu. (16.0 amu x2)

28.0 amu x0.79 + 32.0 amu x0.21 = 29.0 amu

the effective average molecular weight of air is 29.0 amu

Acetylene has a molecular weight of 26.0 amu.

[Acetylene=HC2H, C=12.0 amu, H=1.01 amu, (12.0 amu x2+1.01 amu x2=26.0 amu)]

26.0 amu < 29.0 amu thus acetylene is roughly 10% lighter than air.

Arc welding uses an electric arc to melt and join metal pieces together, while resistance welding uses heat generated by the resistance to electric current flow between two metal pieces to join them together. Arc welding is more versatile and can be used for various types of metals, while resistance welding is more suited for high-speed production and is commonly used in automotive and appliance manufacturing.

The complete path for an electric current to follow is called a circuit. It includes a closed loop with a source of electricity, conductive material, and devices that use the electricity.

A fusion zone in welding is the area where the base metals have melted and fused together to form a strong joint. It is created by the heat generated during the welding process and is essential for producing a solid and durable weld. The quality of the fusion zone is crucial for the overall strength and integrity of the welded joint.

Diarthrotic joints have free movement e.g. synovial joints of knee, elbow, shoulder

synarthrotic = no movement eg skull plates (yes they are a type of joint strangely enough)

amphiarthrotic = some movement eg intervertebral discs

welds are made up of the base material (the metal you had before welding) and a filler material (what you see in addition to the base material) the most common materials welded are steel, aluminum, and stainless steel, and then alloys of each. The filler material can be an exact match to the base, but is usually a compatible alloy containing some other metal to aid in welding i.e. carbon, magnesium, etc

Thermite welding is a process that uses a chemical reaction to create intense heat to join two pieces of metal together. It involves a mixture of aluminum powder and metal oxide that, when ignited, produces temperatures high enough to melt the metal. This method is commonly used to join railroad tracks and other large metal structures.

It is usually green, but owner-bottles (those not owned and rented out by a welding company) can be any color. There should always be a label on all cylinders identifying the contents. Never go just by color.