| abstract |
FIELD: chemistry. n SUBSTANCE: lubricant coating contains one or more base lubricants selected from a basic salt of sulphonic acid, basic salt of salicylic acid, basic salt of phenol and basic salt of carboxylic acid, and at least one additional lubricant, characterised biodegradability which is higher than that of the base lubricant. The additional lubricant is selected from a fatty acid metal salt and wax. The composition is characterised by biodegradability value equal to at least 20% when measured in sea water after 28 days. The composition preferably contains 55-70 pts. wt of the base lubricant, 20-25 pts. wt of the fatty acid metal salt and 10-20 pts. wt of wax and 0-30 wt % of a volatile organic solvent medium. The threaded joint which is meant for joining oil and gas pipes has a coating whose thickness is at least 10 mcm. The joint may also be used without applying grease containing heavy metals. n EFFECT: improved biodegradability, lubricating power and anti-corrosion properties. n 8 cl, 2 tbl, 4 ex, 3 dwg |