Features of Chain Drive Drilling Rig:
1. The rig is powered by diesel engines + coupling forward drive box.
2. The drum of drawworks is grooved. Main brake is hydraulic disc brake and auxiliary brake is electromagnetic eddy current brake. Cat head drawworks is equipped with sand drum.
3. Drawworks of rigs with nominal depth above 4000m is split type and can be installed above or under the drill floor. Drawworks is equipped behind the back of drill floor; Through the bevel gear box and cardan shaft, the power is transmitted up to the drill floor to drive the cat head drawworks and rotary table.
4. Integral chain box compound; Rig is equipped with high power triplex single action mud pumps which are driven by cardan shaft.
5. Key mechanical parts of rig conform to API spec and mark API monogram.
| Model of rig | ZJ30/1700L | ZJ40/2250L | ZJ50/3150L | ZJ70/4500L | |
| Nominal depth, m(ft) | 114mm (4 1/2 in. ) DP | 1600-3000 (5250-9850) | 2500-4000 (8200-13200) | 3500-5000 (11500-16400) | 4500-7000 (14800-23000) |
| 127mm (5 in. ) DP | 1500-2500 (4920-8200) | 2000-3200 (6600-10500) | 2800-4500 (9200-14800) | 4000-6000 (13100-19700) | |
| Max. static hook load, kN (kips) | 1700(382) | 2250( 496) | 3150( 695) | 4500( 992) | |
| Rated power of drawworks, kW(hp) | 550( 750) | 735 ( 1000) | 1100 ( 1500) | 1470 ( 2000) | |
| Type of main brake | Disk brake /Band brake | Disk brake /Band brake | Disk brake /Band brake | Disk brake /Band brake | |
| Type of auxiliary brake | Eddy current brake / Eaton brake | Eddy current brake / Eaton brake | Eddy current brake / Eaton brake | Eddy current brake / Eaton brake | |
| Opening diameter of rotary table, mm(in) | 520.7(201/2) | 698.5 (271/2) | 952.5 (371/2) | 952.5 ( 371/2) | |
| Mast effective height, m(ft) | 41( 134) | 43 ( 142) | 45 ( 147 ) | 45 ( 147 ) | |
| Drill floor height, m(ft) | 5(16.4), 6(19.7), 7.5(25) | 5(16.4), 6(19.7), 7.5(25) | 7.5(25), 9(30), 10.5 (35) | 7.5(25), 9(30), 10.5 (35) | |
| Drill floor clearance height, m(ft) |
3.76(12.4), 4.76 (15.6), 6.26(20.5) |
3.76(12.4), 4.76 (15.6), 6.26(20.5) |
6.12(20), 7.62 (25), 9.12 (30) | 6.12(20), 7.62 (25), 9.12 (30) | |
| Note: L – Chain compound | |||||
