Heavy-weight drill pipe is made from AISI 4145H steel, after all the heat treatment of materials, all physical properties comply with recent provisions of API specification 7. Integral heavy weight drill pipe is a common transition between the drill pipe and drill collars of the drill, which can effectively alleviate the drill collars and transition in the combined stress concentration provides drilling, and can effectively reduce the drill and the wear rate of the connection area and diameter of the borehole. Drill pipe in central part of the thickened, welding joints and thickened in the middle part of the appearance of cemented carbide wear, can effectively protect the pipe from wear and tear. In a soft case of geological formations, heavy weight drill pipe can replace the drill collar to solve a series of problems occurred in vertical drilling. Here are some characteristics and advantages of heavy-weight drill pipe:

1. Extra length of tool joints provides plenty of space to operate while reducingwear rate and extending the service life of the outer diameter.

2. In order to extend the service life of the connection, API Bore Back Box adopts the larger size, whose function is four times as large as the other entire box.

3. The entire centre upset protects the tube from outer diamete wear by keeping the tube away from the hole wall, while at the same time reducing the risk of differential sticking.

4. HWDP with the drill pipe elevator can quickly and effectively deal with the task of drilling platform.

5. Research shows that 95% of the cause for drill string failure can be attributed to fatigue failure. However, the structure of HWDP has high fatigue strength.