... to meet operation space 2.Throughout the drilling process , there is no need to replace the blowout preventer. Composite wellhead (API 6A ... ,CC,DD,EE,FF,HHSpecification level: PSL1-4Performance Requirement: PR1-2 Description:Design casing head and tubing head integrally to meet ... ,CC,DD,EE,FF,HHSpecification level: PSL1-4Performance Requirement: PR1-2 Composite Wellhead (API 6A Series)