U-Bend

U-Bend is a pipe fitting that is folded back 180 degrees, with parallel ends and overlapping centerlines. It is commonly used in pipeline systems where a 180 degree turn is required, especially for pipeline designs with limited space or the need to form loops. Its structure is symmetrical, with uniform flow resistance, which can effectively reduce pressure loss during medium transportation.

There are various material choices, including carbon steel (such as 20 #, A105), stainless steel (304, 316L), and alloy steel pipes (12Cr1MoV, Inconel 600), which need to be adapted according to the characteristics of the medium (temperature, pressure, corrosiveness). For example, 316L U-bend pipes are suitable for chlorine containing media, while alloy steel pipes can withstand high temperatures above 600 ℃.

The manufacturing process is mainly based on hot pressing: after heating the straight pipe blank to a plastic state, it is bent into a U-shape through a mold, and the internal stress is eliminated through heat treatment to ensure uniform wall thickness at the bent part (deviation ≤ 10%). For thin-walled or small-diameter U-shaped bends, cold bending technology can also be used, but stress relief annealing is required.

Its core advantage lies in the ability to reduce the number of pipe fittings (replacing two 90 ° elbow combinations), lower the risk of leakage, and facilitate pipeline cleaning and maintenance. Widely used in heat exchanger tube bundles (such as boiler economizers, chemical condensers), nuclear power pipeline circuits, and clean pipelines in the food and pharmaceutical industry.

The product must comply with standards such as ASME B16.9 and GB/T 12459. The common bending radius is 1D-3D (D is the nominal diameter), and the pressure rating covers Sch40 to XXS, which can meet the requirements of working conditions from low pressure to ultra-high pressure. During installation, it is necessary to ensure that the ports at both ends are concentric to avoid additional stress.