Kelly bar is the key component in the execution of boreholes by hydraulic rotary drilling rigs. Teleskopic Kelly bars transfer torque and crowd force from the rotary drive to the drilling tool. Teknofor Co is a highly specialized manufacturer of telescopic kelly bars to be applied to any type of piling rig available in the market such as Bauer, Sany, Xcmg, Zoomlion, Sunward, Soilmec, IMT, Mait.... Kelly bars are featuring specific construction details:
• 15 - 150 m • torque transfer capacity •• • locks and wear-resistant drive rails (accordingly with rotary sleeve) • bottom shock absorbers
Interlocking Kelly Bar
Friction Kelly Bar
Friction kelly bar derives its name from the means by which it transfer torque to the drilling tool. The telescopic elements are advanced by using the “frictional contact” from each of the friction drive rails that run down the outside of each kelly bar. These drive rails, on the outside of each kelly bar, are driven by the rotary table and the terminal joints of each successively larger diameter kelly bar. The terminal joint is long piece on the inside and at the bottom of each kelly bar. Friction kelly bars are normally supplied in 4 or 5 telescopic elements as they are mostly used for deep piles in medium hard soil conditions.