Method for fabricating an orifice fitting for a gas pressure differential-measuring system

摘要

An orifice fitting for a gas pressure differential-measuring system is constructed of a fabricated body. In the fabrication, two lengths of flared or flanged pipe are inserted through the internal bores of respective orifice blocks and circumferentially welded on the outside. A U-member, which may be assembled of three straight pieces, is welded between the two blocks joining them and leaving a slot at the top. An orifice holder dependingly secured to a cover is provided with an orifice plate rimmed within a gasket and inserted through the slot. The cover is removably, sealingly mounted on the body. The outer face of the upstream face of the gasket is radially notched to equalize pressure in the orifice chamber.