Full interlocking pressurizng kelly bar

Full interlocking pressurizng kelly bar Full interlocking pressurizing kelly bar, allso known as concavo-convex Kai-type pressurizing kelly bar.It is characterized by a external keys composed of three sub-component keys,and each external key top-down are composed of fabric by the convex and concave tine . Driving internal key is composed of three sub-component keys too, and each internal key is also distributed by the composition of convex and concave tine.The internal key and the external key with driving force can be formed lock anywhere and anytime during the drilling process. Driving force head send pressure directly to drill.Currently,the transmission pressure of this drill pipe is the best,especially constructing to the hard layer formation and permafrost;every site of the drill pipe can be formed the pressure point in the course of the drilling , reducing the partial rack (key)of the pressured abrasion ,and also to avoid the drill in a part of the pipe wall deformation caused by the pipe-sticking, at the same time, the convex and concave tine distributed in the driving internal key and external key have a good meshing. In the pressurized part of the formation of multi-point pressure, stress and stability are not sticking cloth, excellent work to improve the efficiency of rotary drilling by many customers! Full interlocking pressurizng kelly barTypeOuter pipe diameter(mm)sectionDepth(m)Torgue(KN.M)JT12/340/3/36-42340336/42120JT15/377/4/42-54377442/46/54150JT20/406/4/48406448200JT22/406/4/48406448220JT25/450/3/40450340250JT25/440/4/56440456250JT25/440/3/40-45440340/45250T28/508/5/70508570280