Pressure indicating bung with self-locking insertion feature

Claim 2

A pressure-indicating bung for a pressure vessel comprising an annular side wall having an externally corrugated, bellows type annular side wall surface, an expansible rim at the bottom of said side wall, a conical bottom wall connected to said expansible rim in sealed relationship therewith, said bottom wall having a central zone thinner than the surrounding area whereby said conical wall will flatten in response to pressure thereon thereby radially expanding said expansible rim and said corrugated wall surface, and an elongated member mounted at one end above said central zone of said bottom wall and upwardly extending therefrom for indicating pressure in response to movement of said bottom wall.

Claim 3

The apparatus of claim 1 further defined by a radially outwardly extending lip connected to the top of said side wall.

Claim 4

The apparatus of claim 2 further defined by an annular top flap having a diameter at least as great as said annular side wall and hinged to said lip at one point for mounting over said lip.

Claim 5

The apparatus of claim 2 further defined by tabs attached to said lip for gripping said bung.

Claim 6

The apparatus of claim 1 wherein the central thin zone of the bottom wall comprises a dimple at the apex of said conical bottom wall.

Claim 7

The apparatus of claim 1 further defined wherein said corrugated side wall surface is a bellows whereby the diameters of said corrugations are minimized with low pressure on said bottom wall and maximized with high pressure whereby said bung locks itself in place upon application of pressure upon said bottom wall.

Claim 8

The apparatus of claim 1 further defined wherein said corrugated side wall surface comprises screw threads.

Claim 9

The apparatus of claim 2 further defined wherein said elongated member extends from said bottom wall to slightly below said annular flap when pressure on both side of said bottom wall is equal.

Claim 10

The apparatus of claim 8 wherein said elongated member is graduated for indicating amounts of pressure.

Claim 11

The apparatus of claim 1 wherein said bung is made of a material which has a yield strength substantially less than said pressure vessel.

Claim 12

A one-piece molded pressure-indicating bung for a pressure vessel comprising an annular side wall having an externally corrugated bellows type wall surface, a radially outwardly extending lip at the top of said wall, and an expansible rim at the bottom of said wall, a conical bottom wall connected to said expansible rim in sealed relation therewith, said bottom wall having a central zone thinner than the surrounding area whereby said conical wall will flatten in response to pressure thereon thereby expanding said expansible rim and said corrugated wall surface, an annular top flap having an outer diameter at least as great as said annular side wall and hinged to said lip at one point for mounting oVer said lip, and an elongated member mounted at one end above said central zone of said bottom wall and upwardly extending therefrom for indicating pressure upon movement of said bottom wall by projection through said annular top flap.

Claim 13

A one-piece molded pressure-indicating bung for a pressure vessel comprising an annular side wall having an externally corrugated bellows type wall surface, a radially outwardly extending lip at the top of said wall, and an expansible rim at the bottom of said wall, a conical bottom wall connected to said expansible rim in sealed relation therewith, said bottom wall having a central zone thinner than the surrounding area whereby said conical wall will flatten in response to pressure thereon thereby expanding said expansible rim and said corrugated wall surface, an annular top flap having an outer diameter at least as great as said annular side wall and hinged to said lip at one point for mounting oVer said lip, and an elongated member mounted at one end above said central zone of said bottom wall and upwardly extending therefrom for indicating pressure upon movement of said bottom wall by projection through said annular top flap.