加重钻杆结构特点是中等重量，类似于钻杆的钻具，其壁厚比钻杆大，比钻链小，般在组成钻柱时加在钻杆和钻链之间，防止钻柱截面的突变，减少钻杆的疲劳。在定向井中使用，可以在较低扭矩的情况下高速钻进，减少了钻柱的磨损和破损，由于其和井壁接触面积小，也不容易形成压差卡钻。加重钻杆执行API 7-1、API7-2标准。
　　Heavy Weight Drill Pipe is one drilling tool which has a medium-weight and similar todrill pipe. Wall thickness is larger than that of the drill pipe, and it is smaller than drill collarGenerally add between the drill pipe and drill collar when compose the drill string, toprevent mutation of cross section of drll string, and reduce the fatigue of drll pipe. When used in directional wel, it can dillwithhigh speed under the condition of lower torque, which reduce the wear and tear of the drll string. Due to the smal sidewalcontact area, it is not easy to form differential pressure sticking. Product standards: API 7-1, API7-2

　　无磁承压钻杆采用自主研发的低碳不锈钢，执行API规范及企业标准，可对螺纹进行冷滚压处理，可加工双台肩螺纹及其它规格的特殊螺纹，可承接各种非标产品。
　　The Non-magnetic compressive service drill pipes are made of low carbon stainless steel.acc.to API Spec.7 and SY/T5144. All threads are phosphated,copperized or coldworked. All Connections areequipped with pressed steel thread protectors. All threadsare machined with CNC Lathes-Doubleshouldered and special threads.

无磁承压钻杆尺寸规格
Non-magnetic compressive service drill pipe specification

注：力学性能参见无磁钻链
Mechanical property refer to Non-maganetic drill collars

磁性能 Magnetic Properties
( 磁场=1 X 10⁵/4πA/m)
1.相对磁导率μr<1.010
Average：μr<1.010
2.磁场梯度： △B≤0.05μT
Magnetic field gradient：△B<0.05μ T