Integral heavy weight drill pipe is made from AISI 4142H—4145H alloy steel, the manufacturing follows SY/T5146—2006 and API SPEC 7—1 standard. Heavy weight drill pipe is one kind of medium weight drill tools seemly with drill pipe, the thickness is bigger than drill pipe and it’s smaller than drill collar, heavy weight drill pipe body has lengthen tool joint. In drill string HWDP be connected between drill pipe and drill collar for preventing drill string section force sudden changing and reducing drill pipe stress fore damage. In direction operation, the HWDP will bring high speed and low torque, and it will reduce drill string damage and friction, also due to the low stress and less hole-wall touches of HWDP can avoid drill string being stuck.
HWDP technical parameters：