Core Barrel here mentioned we normally know it as core retrieval system, common sizes are, DCDMA standard(double tube and triple tube ), T2&T6, X, MLC, chinese single &double system. etc
The core barrel assembly is composed of the inner-tube group and outer-tube group. The inner-tube group is composed of: Head Assembly Inner Tube Stop Ring Core Lifter Core Lifter Case The outer-tube group is composed of: Locking Coupling Adapter Coupling Landing Ring Outer Tube Inner Tube Stabilizer Thread protector (optional)
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