Development of TP-NF/E Coupling Premium Connection with Special Clearance

Based on the structure characteristics of the shale gas well bore and its requirements for the special thread, the TP-NF/E coupling premium connection with special clearance is developed and the development procedure of the special thread P110 TP-NF/E premium connection for size Φ139.7 mm×10.54 mm is described.The anti galling performance, sealing integrity and structural integrity of the TP-NF/E special thread premium connection are evaluated through the finite element analysis and the physical performance test by ISO 13679:2002 CAL II.The result shows that the special thread is designed by use of the hook type thread connection, cone-cone metal sealing surface and torque stopping shoulder with excellent anti galling performance and sealing property, better bending resistance and higher compression resistance, which surely meets the requirement for product design.