Lens Ring Gaskets

Polysiloxanes (silicones) are one of the most studied classes of polymers. They exhibit a variety of useful properties not common to non-metal-contain-ing macromolecules. They are characterized by combinations of chemical, mechanical, electrical, and other properties that, when taken together, are not found in any other commercially available class of materials. The initial footprints on the moon were made by polysiloxanes. Polysiloxanes are currently sold as high-performance caulks, lubricants, antifoaming agents, window gaskets, O-rings, contact lens, and numerous and variable human biological implants and prosthetics, to mention just a few of their applications. 

TYPE OF GASKET DELTA RING BRIDGMAN DOUBLE CONE LENS RING OTHER... 

Lens Ring 45,000 Gasket Matl Depends on configuration Tight tolerances and fine finishes required on gasket groove Mainly used on piping systems... 

There are many modifications of the basic lens ring. The most popular lens ring has spherical faces and is used between flanges with straight, tapered (20°) faces. The line of contact between the gasket and the flange faces is approximately 1/3 of the way across the flange face. 

The gasket consists of a lens shaped ring of heat treated low alloy steel or some other metal. The ring should be softer than the flange face. Flardness of the conventional lens ring varies with the metal required for the service condition. This joint is ideal for pipe and tube applications. It can be used for small connections and can be used for pressure vessel closures but is better suited for piping applications. 

Much of the problems associated with these joints is the non-uniform take up of the flange bolts as well as misalignment of the piping. The lens ring is one of the fastest opening closures. Lens ring gaskets have been used up to about 45,000 PSI. 

Figure 8-27. Piping sub-assy showing, tapered studs, lens ring gasket and clearances for stud tensioning equipment.

Figure 12.10 Lens ring gasket, sealing element, and adjacent parts.

Figure 12.16 Pipe connection with lens ring gasket, DN45, PN500.

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