Application of Maximum Rotary Sidewall Coring Tool in Bohai Oilfield

Compared with the small diameter wall core, the large diameter rotating wall core has a larger volume, which is more conducive to the real evaluation of the formation's petroelectric parameters and geological characteristics, so it is favored by various oilfields. Maximum Rotary Sidewall Coring Tool (MRCT) is a new generation of electrically driven large diameter rotary wellbore coring device launched by COSL with advanced technology and many innovative points. The instrument has made technological innovations and breakthroughs in modular structure design, spacer placement, core length measurement, and drilling speed control of drill bit. Through field operation, MRCT has achieved good results in Bohai Oilfield. Cores can be obtained from soft formations of 140 us/ft to hard formations of 50 us/ft , which meets the demand of large diameter wall cores in Bohai Oilfield and improves the harvest rate of coring. However, there are also some disadvantages in the operation of the electrically driven large diameter rotary wellbore drawing, which need to be improved in the subsequent research and development.