After the water quenching of the drillpipe steel grade, the cooling method of drillpipe welds is changed to the quick water cooling instead of the previous high-pressure air cooling.
钻杆钢种水淬化后，焊缝热处理的冷却方式由以前的高压空气冷却转变为快速水冷却。
2
When picking up drillpipe, visually check each joint of pipe picked up to be sure it is in proper sequence according to weight, grade and class as designed.