Modified Buttress Thread
TBG: 2-3/8in~2-7/8in: 8T.P.I.
         3-1/2in~4-1/2in: 6T.P.I.
CSG: 5in~13-5/8: 5T.P.I.

Metal-Metal Seal
Seal Taper: TBG: 1:1.732
                  CSG: 1:10; 1:6; 1:3
Reverse angel torque shoulder

High performance gas-tight premium connection for casing and tubing

ISO 13679 CAL IV approved

  • Excellent gas seal-ability under combined load
  • Easy stabbing, No cross threading
  • Superior Anti-galling performance
  • Easy repairing
  • Suitable for low alloy & carbon steel pipe


Threaded Connection
Improved Buttress thread with a taper of 1:16. The clearance at the top of the thread crests minimize thread galling and avoid the trapping of compound inside the threads.

Metal-to-Metal Seal
Metal-to-metal seal surface can provide enough contact length and pressure. The metal-to-metal seal system offers excellent gas-tight sealing, even under the most severe combined loads. The seal integrity remains constant after repeated make-ups and break-outs. Optimized thread geometry minimizes the risk of galling, even when thread compounds are poorly applied.

Reverse Angle Torque Shoulder
The reverse angle torque shoulder provides a positive torque stop, which allows accurate power tight make-up and minimizes hoop stresses in the connection. The wedge effect caused by the reverse angle gives the connection a superior structural strength. The shoulder design is optimized in order to resist adverse conditions such as combined compression and external pressure or combined bending, compression and torque.

Streamlined Internal Profile
A pin ID chamfer, tight tolerances on the coupling center combined with a long shoulder will minimize turbulence and energy loss inside the connection for high-velocity gas flows.

Coupling Design
Joint efficiency is more than 100% and coupling critical section is greater than pipe body section. Because the coupling covers the vanishing threads therefore the connection tensile efficiency is maximized.

Connection Low Stress Design
Connection low stress design can ensure that it can be safe under corrosive environment.

TP-CQ HT     High torque;
TP-CQ HC     High compression;
TP-CQ (SB)   Special bevel;
TP-CQ (SC)   Special clearance;
TP-CQ (MS)   Matched strength.