DEVELOPMENT OF SUCTION AND DISCHARGE VALVES USING NON-METALLIC VALVE PLATES FOR BOG COMPRESSORS

摘要

BOG that evaporated in LNG tanks, are typically pressurized using reciprocating compressors and used as the energy source. Since BOG are low temperature, stainless steel materials are used for the suction and discharge valve plates in the reciprocating compressors, but since there is wear due to the contact between the valve plate and valve seat, valve plates must be replaced periodically, and inspection for the valve and adjustments are necessary. Since durability has been improved in recent years, resins have come into use for suction and discharge valve plates in reciprocating compressors in normal temperature ranges, but they have not been used at all in low temperature ranges because of the brittleness of resins. In this instance resin materials with cryogenic properties have been selected, the valve structure improved to alleviate impact forces, and suction and discharge valves made of resin valve plates at low temperatures developed for the first time. Therefore, valve plates with durability approximately twice that of conventional stainless steel valve plates have been realized. The resin valve plates have the following effects compared with conventional stainless steel valve; inspection and maintenance cost reduction: approximately 30% with improvement in durability; power required by compressors reduction: approximately 2.4% with improvement in sealing ability; lowering operating noise: approximately 4% by avoiding metal contact (contact metal and resin). The suction and discharge valves made of resin valve plates are new technology and can be used by factories with same kinds of facilities both domestically and overseas.