Metal Ring Gaskets

The spiral-wound type furnished with a sohd metallic ring on the outside to hmit gasket compression provides protection against blowout when used with raised facing. 

Fig. 1.28 A cross section of a DAC for loading condensable gases. The chamber is sealed with indium (D) diamonds, (G) gasket, (R) metal ring, (In) indium ring, (C) capillary tubing, (T) tungsten carbide seats. (Reprinted with permission from the publisher.)...

Laminated gaskets are fabricated with a metal jacket and a soft filler, usually of asbestos. Such gaskets can be used up to temperatures of about 750 F to 850 F and require less bolt load to seat and keep tight than solid-metal flat-ring gaskets. 

Expanded PTFE that is fibrous in structure and contains microvoids is especially useful for gasketing against uneven or delicate surfaces. With increasing pressure, fillers are added to PTFE to counteract its tendency to creep and cause sealing to deteriorate. For higher pressures, gaskets incorporate metal rings or flat spirals to support sections of PTFE. 

Metallic Gaskets for Pipe Flanges — Ring-Joint Spiral Wound, and Jacketed Nonmetallic Flat Gaskets for Pipe Flanges Buttwelding Ends Steel Line Blanks... 

Radially split casings shall have metal-to-metal fits, with confined controlled compression gaskets, such as an O-ring or a spiral wound type. 

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