The Socket weld flanges are attached by only one fillet weld, only on outside, and are not recommended for severe services. These are used for small-bore lines only. Their static strength is equal to Slip On flanges, but their fatigue strength is 50% greater than double-welded Slip On flanges. The thickness of connecting pipe should be specified for this type of flanges to ensure proper bore dimension.In socket weld flange, before welding, a space must be created between flange or fitting and pipe. ASME B31.1 Preparation for Welding (E) Socket Weld Assembly says:In assembly of the joint before welding, the pipe or tube shall be inserted into the socket to the maximum depth and then withdrawn approximately 1/16″ (1.6 mm) away from contact between the end of the pipe and the shoulder of the socket.The purpose for the bottoming clearance in a Socket Weld is usually to reduce the residual stress at the root of the weld that could occur during solidification of the weld metal. The image shows you the X measure for the expansion gap.The disadvantage of socket weld flange is right the gap, that must be made. By corrosive products, and mainly in stainless steel pipe systems, the crack between pipe and flange can give corrosion problems. In some processes this flange is also not allowed.
Post time: Jul-02-2024