Hose

From GAWDAwiki

Welding hose is used to connect regulators to torches. It must be strong, light, nonporous and flexible enough to allow easy movement. It must be capable of withstanding pressure up to 100 psig, and must be made of rubber specially treated to remove sulfur that could cause spontaneous combustion.

Inside Diameter

Single- and double-line welding hose lengths are available. The appropriate size to use is determined by the type of work to be done.

Light work typically calls for hose with 3/16” or 1/4” inside diameter and one or two plies of fabric.
Heavy-duty welding and cutting may call for 5/16” inside diameter and three to five plies of fabric.

Single hose is available in these standard sizes, as well as 1/2”, 3/4” and 1” sizes. Heavy-duty usage and use with large cutting machines may call for larger sizes.

Length

The length of hose used affects the delivery pressure of the torch. A longer hose leads to lower pressure, so longer hoses should have larger inside diameters in order to allow adequate gas flow to the torch.

Color

Hoses used for fuel gas and oxygen differ in color, but not in construction. Color-coding is a precautionary measure to reduce confusion and dangerous errors.

Red hose is used for fuel gas.
Green hose is used for oxygen.

Connections

Basic hose connections include a nut and a gland. Connections for welding and cutting hoses have all been standardized by the Compressed Gas Association using letter grades followed by the name of the gas being used.