US 5,628,231 A · Sight glass construction

Abstract

An improved sight glass for use in determining the level of water in steam boilers and similar installations is disclosed. The end flanges are provided with molded inserts, preferably of PTFE or similar fluorocarbon material which serves to provide a sealing washer when the device is connected to communicating pipe flanges at an outer surface thereof, and provides a seal at the annular end surfaces of the sight glass. A concentrically disposed guard tube is also maintained in sealed relation relative to the end flanges, and is preferably of polycarbonate or similar material. The guard tube is supported by oppositely disposed rectangular cross-sectioned "O" rings which provide for the sealing of the cylindrically shaped space between the outer surface of the sight glass and the inner surface of the guard tube. Peripherally positioned tie rods prevent excess tightening of the end flanges, thus preventing excess axially oriented pressure on the sight glass.

Claims7

Dependent claims

An improved sight glass construction comprising:

first and second radially extending flange elements, each defining a central opening, and a plurality of radially arranged openings for reception of interconnecting bolts;
said flange elements each defining an annular recess and a stepped recess;
a transparent inner tube member engaging the annular recesses at each end thereof in sealed relation;
an outer tube member surrounding said inner tube member and positioned within the stepped recesses at each end thereof in sealed relation to said first and second flange elements to define a cylindrical sealed interstice between said inner and outer tube members;
and a plurality of tie rods interconnecting, said first and second flange elements in predetermined spaced relation, externally of said outer tube member.

2 more elements

Dependencies are inferred from the claim text.

Sight glass construction

Life of this patent

Sight glass construction

Life of this patent

Abstract

Claims7