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Lens Ring Joint Gasket

Lens Ring GasketWealson manufactures and supplies a large variety of ring joint gaskets. The RTJ standard size gaskets are manufactured in accordance to API-6A and ASME B16.20 specifications.

API ring Joint gaskets come in two basic types, an oval cross section and an octagonal cross section. These basic shapes are used in pressures up to 10,000 psi. The dimensions are standardized and require specially grooved flanges. The octagonal cross section has a higher sealing efficiency than the oval and would be the preferred gasket. However, only the oval cross section can be used in the old type round bottom groove. The newer flat bottom groove design will accept either the oval or the octagonal cross section. The sealing surfaces on the ring joint grooves must be smoothly finished to 63 micro inches and to be free of objectionable ridges, tool or chatter marks. They seal by an initial line contact or a edging action as the compressive forces are applied.

The hardness of the ring should always be less than the hardness of the flanges to prevent flange deformation. Dimensions for API ring joint gaskets and grooves are covered in ASME B16.20 and API6A.

Lens Ring Joint Gasket
A lens type gasket is a line contact seal for use in high pressure piping systems and in pressure vessel heads. The lens cross section is a spherical gasket surface and requires special machining on the flanges. These gaskets will seat with a small bolt load since the contact area is very small and gasket seating pressures are very high. Normally the gasket materials should be softer than the flange. In ordering lens gaskets, complete drawings and material specifications must be supplied.

index_ic01Materials: soft iron,SS304, SS316, carbon steel , SS321 and the other alloy material.
index_ic01 With high temperature, high pressure and corrosion resistance of the excellent characteristics.
index_ic01Mainly used in high temperature and high pressure pipe (steam and oil industry, petroleum chemical industry) tower, tank, heat exchanger, the pipe joints.
index_ic01Standard: ANSI B16.5-1973 、 JPI-75-15-70 、 GB 699 、 GB1220 、 JB755 、 HG20633-97

Oval RTJ Gasket Standard: ANSI B16.5-1973 、 JPI-75-15-70 、 GB 699 、 GB1220 、 JB755 、 HG20633-97
Octagonal RTJ Gasket