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.
| Name of product | External diameter (mm) | Pitch No | Length section (m) | Rated torque (KN*M) | Depth (m) |
| Friction kelly bar | 355 | 4,5 | 10-13 | 180 | 36-60 |
| 377 | 4,5 | 10-14 | 200 | 36-65 |
| 406 | 4,5 | 10-15 | 210 | 36-70 |
| 419 | 4,5 | 10-15 | 250 | 36-70 |
| 440 | 4,5 | 10-15 | 250 | 36-70 |
| 470 | 4,5,6 | 10-17 | 280 | 36-95 |
| 508 | 4,5,6 | 10-18.5 | 320 | 36-103 |
| 530 | 4,5,6 | 10-19 | 380 | 36-106 |
| 575 | 4,5,6 | 10-21 | 420 | 36-120 |
| 630 | 4,5,6 | 10-21 | 450 | 36-120 |
| Name of product | External diameter (mm) | Pith No | Length section (m) | Rated torque (KN*M) | Depth (m) |
| Interlocking kelly bar | 355 | 3 | 10-13 | 180 | 27-36 |
| 377 | 3,4 | 10-12.5 | 220 | 27-44 |
| 406 | 3,4 | 10-15 | 230 | 27-57 |
| 419 | 3,4 | 10-15 | 250 | 27-57 |
| 440 | 3,4 | 10-15 | 250 | 27-57 |
| 470 | 3,4 | 10-17 | 280 | 27-65 |
| 508 | 3,4 | 10-17 | 320 | 27-65 |
| 530 | 3,4 | 10-20 | 380 | 27-76 |
| 575 | 3,4 | 10-21 | 420 | 27-80 |
| 630 | 3,4 | 10-21 | 450 | 27-80 |
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.
