Manifolds are used widely in the oil and gas industry for the distribution of process fluid such as oil, gas, and water. The sizes of manifolds are selected by process engineers based on the flow rate passing through the manifold. Manifolds normally handle high-pressure fluid. In the offshore industry, manifolds are made in 22Cr DSS instead of carbon steel to save thickness and weight. Offshore Manifolds are made of either welding wrought tees or using a standard pipe as a header and welding olets to the pipe header. Bevel ended long length tees on the manifolds should be welded together through butt welding.

Welding techniques traditionally, preparation of the welded ends was done as per ASME B16.25, the common standard for butt welded connections in piping systems including manifolds, however, narrow gap welding is an advanced welding end preparation in which the angle of bevel end fitting has 7° to the vertical line. The advantages of narrow gap welding include using fewer weld electrodes, having a faster welding process, and requiring less heat input. This proces for calculating welding consumables volume and weight in one-meter shows that the amount of welding electrodes used for standard ASME welding is more than double the amount of narrow gap welding.