According to the service conditions and application requirements of the pipe for the support system of the jack-up drilling platform the chemical composition of X100QO steel heavy-walled pipe has been designed. The Φ406 mm X 45 mm X100QO large-diameter heavy-walled seamless steel pipe is produced by process of "70 t EAF→ LF + VD→CCM Φ460 mm round billet—>ASSEL rolling一quenching and tempering

''

. By control of purity of steel and dimensional accuracy of tube in production process

according to the test results the quenching temperature is 950°C

water cooling

tempering temperature is 530°C

air cool process. The test results show that the seamless pipe has high strength

excellent impact toughness and good welding performance

fully meets the design and use requirements of the pipe for the support system of the jack-up drilling pla

tform

and has passed the certification of ABS American Classification Society.