Shaft seals packing materials

Cast iron is the standard material used to construct the cylindrical housing, but other materials may be used if corrosive conditions exist. The rotor is usually a continuous piece of steel that includes the shaft and is made from bar stock. Special materials can be selected for corrosive applications. Occasionally, the rotor may be a separate iron casting keyed to a shaft. On most standard air compressors, the rotor-shaft seals are semi-metallic packing in... 

Nitrile rubbers, including fiber-reinforced varieties, are used both as radial shaft-seal materials and as molded packing for reciprocating shafts. They have excellent resistance to a considerable range of chemicals, with the exception of strong acids and alkalis, and are at the same time compatible with petroleum-based lubricants. Their working temperature range is from —1°C to 107°C (30°F to 225°F) continuously and up to 150°C (302°F) intermittently. When used on hard shafts with a surface finish of, at most, 0.00038 mm root mean square (RMS), they have an excellent resistance to abrasion. 

A device that effectively seals a pump against leakage around the shaft by means of various rubber/fiber packing materials. 

Packing material provides a seal in the area where the pump shaft penetrates the pump casing. 

Leakage— joints and packing Gaskets, seals of joints or shafts can be sources of leaks of flammable or combustible materials. Depending on the quality of the design of the process unit and the type of material involved penalty factors between 0.1 and 1.5 are assigned. 

Charging manholes, agitator shafts shall be provided with gland packing of compatible materials or shall be water-cooled type to prevent escape of vapours. Mechanical seals may be fitted in case there is a possibility of escape of toxic or inflammable vapours. 

---