COSL has six domestic-sited operation bases and more than 700 professional personnel. Being certified by DNV, it can provide various tailor-made services supporting by its own offshore conductor-driving penetration analysis software, casing cutting and beveling equipment, and adapted 26" casing power tongs. COSL has been widely acclaimed by CNOOC, Petro China, SINOPEC, Shell, ,ENI , Conoco-Phillips, Devon Energy , and ROC Oil for providing excellent quality, high efficiency, and superior service.
The main services include：
· Conventional casing and tubing running service of 36"to 2⅜"
· Casing of 13CR-alloy and tubing running service ranging from 13⅜" to 2⅜"
· HTHP and special-sizes casing and tubing running
· Highly-deviated-well surface casing running
· Special thread type casing and tubing running
· Conductor driving
· Casing cutting
· Locking/unlocking service
· CRT/CDS top driving casing running
· Wellhead assembling/ disassembling
