Teleskopic Kelly Bar High Precision High Reliability Small Clearance Heat treatment

Kelly bars are key components 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.

A kelly bar consists of 2-5 telescopic tubular section with a system of drive keys and lock recesses weld onto their outer surface.

Standard kelly bars are fabricated with a total of 6 drive keys on each section .

We have two kinds of kelly bar according to the rich manufacturing experience and the advanced technology:interlocking and friction.

Frictional kelly bar is convenient and fast to lift the bar because it does need to lock the joint of its inner and outer lining .

Non-stair key, friction transmission the outside key is made by highly wear-resisting tempering steel.

For layer of soft ground and mud, mud, (mud) sand, gravel

Interlocking kelly bar has 3 rigid parts between drilling pipes to transfer greater pressure from embedding cylinder.

It is of great pressure transmission and good anti-contortion perfomance,even at the hard geologic condition it can transfer greater pressure and drill in.

Stair key, organization transmission, the outside key is made by highly wear-resisting tempering steel. For soft fromations, (weak) weathered rock, hard strata construction.

1. The advantages of our Kelly bar, such as low weight, high strength, high abrasion-resistance, high-reliability are safeguarded.

2. Main body made of alloy hot-treated specially enjoy both high hardness and perfect welding performance, high abrasion-resistance leads to high-reliability.

3. Heat treatment is widely used in the key parts such as drive key to improve wear resistance

4. Small clearance and high-precision mating of the drill pipe ensure its good working order and service performance.

5. Fulfill the rotary drilling rig full torque operation.