Standard Square Kelly is made from AISI 4145H alloy steel according to API Spec7-1. We can offer Square Kelly and Hexagonal Kelly. Kelly's ends drive cross-section and joint are all processed and tested in terms of API Spec7-1.
It is formed through hot forging and fully heat-treated by intermediate frequency induction heat treatment or 20m horizontal optical resistance furnace. Threads can be phosphated, copperized or cold worked.
Features:
1. We can manufacture square kelly and hexagonal kelly as per requirements of customers.
2. They are made of AISI 4142H-4145H forged or rolled alloy structural steel. Quenching plus tempering thermal treatment will be conducted over the whole length. Its Brinell hardness can reach 285-341 on the basis of such thermal treatment. Charpy impact energy: 54J. The formulated process can ensure that the misalignment of the hole reaches the standard wall thickness.
| Size | Length in | Upper box connection | Lower pin connection | I.D. | Driving section | |||||||
| mm | in | Type(LH) | O.D. | Thread | O.D. | Cross flat | For square kelly | Cross corner for hexa kelly | ||||
| Std | optional | Std | optional | |||||||||
| 63.5 | 2 1/2 | 12.19 | 6 5/8REG | 4 1/2REG | 196.8 | 146.0 | NC26 | 85.7 | 31.8 | 63.5 | 83.3 | |
| 76.2 | 3 | 12.19 | 6 5/8REG | 4 1/2REG | 196.8 | 146.0 | NC31 | 104.8 | 44.4 | 76.2 | 100.0 | 85.7 |
| 88.9 | 3 1/2 | 12.19 | 6 5/8REG | 4 1/2REG | 196.8 | 146.0 | NC38 | 120.6 | 57.2 | 88.9 | 115.1 | 100.8 |
| 108.0 | 4 1/4 | 12.9 | 6 5/8REG | 4 1/2REG | 196.8 | 146.0 | NC46 | 158.8 | 71.4 | 108.0 | 141.3 | 122.2 |
| 6 5/8REG | 4 1/2REG | 196.8 | 146.0 | NC50 | 161.9 | 71.4 | 108.0 | 141.3 | 122.2 | |||
| 133.4 | 5 1/4 | 12.9 | 6 5/8REG | 196.8 | 5 1/2FH | 177.8 | 82.6 | 133.3 | 175.4 | 151.6 | ||
| 6 5/8REG | 196.8 | NC56 | 177.8 | 82.6 | 133.3 | 175.4 | 151.6 | |||||
Process procedure
Package
When ordering Please specify:
1. Kelly type (square or hexagonal);
2. Nominal size and overall length;
3.Upper and lower Connections.
