<pre id="g6fxz"><dfn id="g6fxz"></dfn></pre>
    1. <dfn id="g6fxz"></dfn>
      波多野结衣一区二区三区高清,精品国产人成亚洲区,日本高清不卡aⅴ免费网站,日本肥老妇色xxxxx日本老妇,久久精品熟妇丰满人妻99,欧洲成人一区二区三区,国产无吗一区二区三区在线欢 ,欧美成人精精品一区二区三区

      Products & services

      Hilong Double-Walled Drill Pipe

      Product Introduction 

      Double-walled drill pipe is composed of two layers pipes. It is mainly used in reverse circulation drilling technique. The outer drill pipe is the transmission medium of torque and pressure, the space between outer and inner pipes is a channel for pumping circulating medium to well bottom, the inside channel of inner drill pipe returns the circulating medium and rock chips to the outside.

      Product Advantage

      ·No wash out from the walls of a well, reservoir protection, no limit to drill collapse layer and loss formation;
      ·Less drilling fluid, smaller displacement and faster return speed, the hole is clean;
      ·Unique advantage in directional well, horizontal well and continuous sampling;
      ·Suitable for large hole drilling, improving drilling efficiency.New drilling techniques have been developed on the basis of double-walled drill pipe, the most typical representative of it are RDM (Reel Well Drilling Method) and RCCD (Reverse Circulation Centre Discharge).

      Product Specification

      Size Range (OD of external layer pipe):
      Normally 5", 5 1/2", 5 7/8", 6 5/8", 7 5/8", 8 1/2", 9 1/2" and 10".