Combined-interlock Kelly bar is composed of interlock Kelly bar and full multi-interlock Kelly bar.

For this type of Kelly bar , the first section is 3-keys interlock type, inner few sections are multi-type step keys , the outer keys are three- sections with three set of concave and convex form .

Specification

Beijing Jietaihongli Technology Co., Ltd., founded in 2004, headquartered in Beijing, branch factory in Shouguang, Shandong. The company is mainly engaged in the production and sales of rotary piling kelly bars , drilling tools, rotary piling rig overhaul, rig sales and accessories supply.

Beijing Jietai Haoli Technology Development Co., Ltd. is one comprehensive enterprise that produces and sells rotary drilling kelly bars ,drilling tools,piling rigs spares and piling rig maintenance.The company established in 2004. The founder has been engaged in after-sales service of drilling rigs and kelly bars such as IMT, SOIMEC, BAWER, and MAIT before the establishment of the company. During this period he accumulated rich experience in kelly bar manufacture and maintenance.The company focused on the research, development and production of kelly bars after establishment. The main kelly bars produced include frictional kelly bars ,interlocking kelly bars and square kelly bars.