PRESSURE SENSOR AND TRANSMITTER HAVING A WELD RING WITH A ROLLING HINGE POINT

摘要

A process control instrument (10) adapted to provide an output indicative of a parameter of a process fluid is disclosed. The process control instrument is designed to be attachable to a flange (13) having a first passageway (24) filled with process fluid. A body (12) of the process control instrument has an opening (28) adjacent to the first passageway adapted to receive process fluid from the first passageway. An isolation diaphragm (46) is positioned in the opening of the body and separates the opening and the first passageway from a second passageway (32). A weld ring (48) positioned in the opening is provided with an acurate or curved transition surface between a contact surface (206) being positioned against the isolation diaphragm (46) and a neighbouring surface (207) so as to evenly distribute an attachment force across a support surface (49) such that damage to the isolation diaphragm is minimized.