Active Member
|
[China]
Address: B2-0645 ROOM, CENTURY-TEA-TRADE-CENTER, NO.10 MALIANDAO ROAD, XUANWU DISTRICT, BEIJING, CHINA
Contact name:Jade
FLRT Bit |
|
|
12 1/4" FA637G , Tricone Bit , Well Drilling Bit , Fluid Circulation , TCI Rock Bit , TRC Bit
RECOMMENDED DRILLING PARAMETERS FOR APPLICATION
| Types & IADC Code | 417 | 437 447 | 517 527 | 517 527 | 537 547 | 617 627 | 637
| |
| WOB | KN/mm(Bit Dia.) | 0.4~0.9 | 0.4~0.9 | 0.35~1.0 | 0.35~1.0 | 0.5~1.0 | 0.6~1.1 | 0.7~1.2 |
| Lb/in. (Bit Dia.) | 2285~5142 | 2285~5142 | 2000~5714 | 2000~5714 | 2857~5714 | 3428~6285 | 4000~6857 | |
| Rotation Speed (Rpm) | 140~60 | 240~70 | 125~50 | ~60 | 110~50 | 100~40 | 80~4 | |
All bearing materials must be made of toughened steel which has a high resistance to chipping and breaking under the severe loading they must support.
As with all rock bit components, heat treatment is used to strengthen the steel.
The most important factor in the design of the bearing assembly is the space availability.
Ideally the bearings should be large enough to support the applied loading, but this must be balanced against the strength of the journal and cone shell which will be a function of the journal diameter and cone shell thickness.
The final design is a compromise which ensures that, ideally, the bearings will not wear out before the cutting structure (i.e. all bit components should wear out evenly).
However, the cyclic loading imposed on the bearings will, in all cases, eventually initiate a failure.
When this occurs the balance and alignment of the assembly is destroyed and the cones lock onto the journals.
