28 Oxyfuel Welding, Cutting, and Brazing

Oxyfuel welding and oxyfuel cutting involve which of the following processes?

• Using a flame produced by burning a fuel gas with oxygen to weld or cut metals.

• Using only electrical energy to join or cut metals.

• Applying mechanical force to separate or join metals without heat.

• Using chemical adhesives to bond metal surfaces.

The characteristics of gases used with oxyfuel torches are:

• They support combustion and have high purity.

• They are always liquid at room temperature.

• They are non-flammable and inert.

• They are heavier than air and toxic.

The equipment used with oxyfuel welding and cutting includes:

• Oxygen and fuel gas cylinders, regulators, hoses, torch, and cutting attachments

• Electric arc welder, electrode holder, and ground clamp

• TIG torch, tungsten electrode, and shielding gas

• Plasma cutter, air compressor, and power supply

Safe handling and storage of gas cylinders involves:

• Keeping cylinders upright and secured

• Storing cylinders near heat sources

• Laying cylinders flat on the ground

• Leaving valves open when not in use

Safe practices for working with oxyfuel equipment include:

• Checking for leaks before use

• Ignoring damaged hoses

• Using equipment near flammable materials

• Leaving valves open when not in use

Properly lighting and shutting down an oxyfuel torch involves which of the following steps?

• Open the fuel and oxygen valves slightly, ignite the torch, adjust the flame, and to shut down, close the fuel valve first, then the oxygen valve.

• Open both valves fully before lighting, ignite with a match, and to shut down, close the oxygen valve first, then the fuel valve.

• Light the torch with both valves closed, then open them after ignition, and to shut down, close both valves at the same time.

• Open only the oxygen valve to light, ignite the torch, and to shut down, close the oxygen valve only.

Differentiate between types of oxyacetylene flames and their applications.

• Oxyacetylene flames are classified as neutral, carburizing, and oxidizing, each used for specific welding applications.

• Oxyacetylene flames are only used for cutting metals and have no other types.

• Oxyacetylene flames are classified as hot and cold, with no specific applications.

• Oxyacetylene flames are only used for heating and do not vary in type.

Using a cutting torch involves which of the following steps?

• Adjusting the gas flow, lighting the torch, and moving the flame along the cut line

• Submerging the torch in water before use

• Using only oxygen without any fuel gas

• Cutting metal without wearing any protective gear

The process of welding with an oxyacetylene torch involves:

• combining oxygen and acetylene gases to produce a high-temperature flame for melting and joining metals

• using only oxygen to heat and fuse metals

• joining metals by applying electric current

• melting metals with a laser beam

Brazing and braze welding differ in the way the filler metal interacts with the base metal. Which statement best compares and contrasts these two processes?

• Brazing uses capillary action to join metals, while braze welding deposits filler metal without capillary action.

• Both brazing and braze welding use capillary action to join metals.

• Braze welding uses a lower temperature than brazing.

• Brazing and braze welding both melt the base metal to form the joint.