Chinese mud technology services are under each drilling company, short of independent and specialized mud technology service companies. Biggest Chinese mud technology service company is Great Wall Drilling Fluid Company, mainly providing drilling fluid, solids control, waste management and other integrated services.
Previously, domestic mud companies are all state owned mud companies affiliated with CNPC, Sinopec and CNOOC. With market development and opening up, more and more mud companies appear in Chinese market. Foreign invested companies have successively entered Chinese oilfield service market, so do domestic private mud companies.



According to incomplete statistics, foreign invested mud companies in China include:

Powerful private mud companies include:

 

Most of the operations for foreign invested mud companies are in oilfield blocks of foreign invested oil companies, mostly offshore drilling. M-I SWACO, SCOMI, HALLIBURTON and BAKER HUGE all have their operations in Bohai gulf and South China Sea. Foreign invested oil companies in these sea areas include CONOCOPHILLIPS, CACT, CHERVON, KERR-MCGEE,ROC, HUSKY, etc. Above mentioned mud companies provide mud services for them, both for their reliable technology, standard management, trustworthiness, and for their habit of using oil-based mud, which is advantage for M-I SWACO and other mud companies. Foreign invested mud companies and oil companies form close cooperative relationship in this way. 



Most of the foreign invested companies use oil-based mud in Chinese oilfield services market. Due to its advantages and excellent performance in deep well, extra-deep well and complex well, oil-based drilling fluid becomes mainstream on drilling fluid market for foreign invested companies.
Besides offshore drilling, foreign invested companies also have operations on land. SHELL has its drilling operations in Sichuan and northern Shaanxi area, CHERVON in Sichuan and TOTAL in northern Shaanxi area. Mud companies cooperating with these companies include foreign invested company like MISWACO and companies affiliated with CNPC. Both Petro-king and Renzhi Oil Service have cooperation with owner oil companies, providing mud engineering service for them in Xinjiang and Daqing oilfields. Additionally, other small and medium domestic mud companies are offering drilling fluid services for owner companies of CNPC and Sinopec.