Abstract: A pressure gauge fabricated from directly welded pieces of dissimilar metals. The gauge includes a casing, a tubular socket, and a Bourdon tube. The casing is fabricated of stainless steel and has an aperture with a flange. The socket is fabricated of aluminum bronze and is positioned within the aperture and flange in line contact therewith. The tubular socket also has a bore. The Bourdon tube is fabricated of stainless steel and is positioned within the bore in line contact therewith. Single weld lines exist along the lines of contact between the casing and the socket and between the socket and the Bourdon tube as caused by welding without a filler or insert material operatively associated with the single weld lines.

Abstract: Bourdon tubing is constructed from metal strip by roll forming the strip into a desired tubular cross section with the opposed edges abutting longitudinally at a location in the cross section at which contemplated operational stresses are predetermined to be relatively low. After continuously welding the edges in a pressure-tight relation, the tubing can be shaped along its length into a Bourdon tube configuration without need for further metallurgical mill processing.

Abstract: A prepackaged pressure responsive diaphragm sub-assembly of the flange type for isolating a pressure sensitive instrument from the source of fluid pressure at a connection with which the instrument is to be utilized. Comprising the sub-assembly unit is an annular diaphragm retained prepackaged in operative relation sandwiched between a housing and an open ended sleeve having an end face adapted for gasket sealed installation with a match-up sleeve provided by the end user. Securing the assembly are L-shaped fasteners supported in an annular flange mounted about the housing and gripping a shoulder formed on the sleeve. Displaced in the flange from the fasteners are bolt holes enabling installation to a flange on the user's pressure source connection while maintaining the prepackaged operative relation of the sub-assembly.

Abstract: A corrosion resistant Bourdon tube for pressure gauges and the like formed of a vacuum purified ferritic stainless steel containing by weight about 26 percent chromium, about 1 percent molybdenum and ultra-low carbon and nitrogen content on the order of about 0.002 and 0.008 percent, respectively. By virtue of the metallurgical structure of this composition affording good weldability and ductility, a Bourdon tube fabricated therefrom is characterized by substantial immunity to chloride stress cracking, and high resistance to both sulfide damage and pitting corrosion.