HDS Roller Kelly Bushing is heavy type, suitable to square drive.They are designed and manufactured according to API Spec 7K Specification for drilling and well servicing equipment.
Model |
Applicable Size of Kelly(in) |
Drive Way |
Master Bushing | |
|
HDS |
Square（SQ） |
2.1/2-6 |
Square drive |
17.1/2-27.1/2 |
|
Hex（HE） |
3-6 | |||