API Certified Roller Kelly Bushings from China - Reliable Suppliers and Factory for Superior Drilling Performance
Roller Kelly Bushing Specifications
1. Light Duty Roller Kelly Bushing
| Model | 20-MDP | 17-MDP | LDS |
|---|---|---|---|
| Max Torque | 13729 N·m (10126 ft·lbf) | - | - |
| Drive Type | Square | - | - |
| Square Kelly Size | 63.5-133.35 mm (2 1/2-5 1/4 in) | - | - |
| Hexagonal Kelly Size | 76.2-107.95 mm (3-4 1/4 in) | - | - |
| Dimensions | 458×458×700 mm (18×18×27.5 in) | 508×508×700 mm (20×20×27.5 in) | - |
| Weight | 460 kg (1012 lb) | 340 kg (750 lb) | 400 kg (808 lb) |
2. Medium-Duty Roller Kelly Bushing
| Model | 20-HDP | MDS |
|---|---|---|
| Max Torque | 13729 N·m (10126 ft·lbf) | - |
| Drive Type | Square | Pin Shaft |
| Square Kelly Size | 63.5-133.35 mm (2 1/2-5 1/4 in) | - |
| Hexagonal Kelly Size | 76.2-107.95 mm (3-4 1/4 in) | - |
| Dimensions | 493×493×696 mm (19.4×19.4×27.4 in) | 510×510×720 mm (20×20×28.3 in) |
| Weight | 670 kg (1470 lb) | 420 kg (924 lb) |
3. Heavy Duty Roller Kelly Bushing
| Model | HDS | 27-HDP |
|---|---|---|
| Max Torque | 32365 N·m (23871 ft·lbf) | 22555 N·m (16636 ft·lbf) |
| Drive Type | Square | Pin Shaft |
| Square Kelly Size | 76.2-152.4 mm (3-6 in) | 63.5-133.35 mm (2 1/2-5 1/4 in) |
| Hexagonal Kelly Size | 76.2-152.4 mm (3-6 in) | 76.2-107.95 mm (3-4 1/4 in) |
| Dimensions | 630×630×740 mm (24.8×24.8×29.1 in) | 630×630×780 mm (24.8×24.8×30.7 in) |
| Weight | 700 kg (1540 lb) | 730 kg (1610 lb) |
Roller Kelly Features
1. Versatility
Compatible with a wide range of Square and Hexagonal Kelly sizes.
2. Friction Reduction
Quad-roller precision design, four induction-hardened rollers reduce frictional resistance by up to 68% compared to solid bushings.
3. API Compliant Connections
Available with various standard connection types to meet different rig configurations.
Middle Eastern Rig Case Study
"In a Middle Eastern rig operation, heavy duty pin drive bushings reduced torque fluctuations by 35%, resulting in a 50% increase in Kelly service life compared to standard bushing systems."
Frequently Asked Questions
What are the primary differences between Light, Medium, and Heavy Duty Roller Kelly Bushings?
The primary differences lie in their maximum torque capacities, weights, dimensions, and drive configurations. Light Duty models (like 20-MDP) support torque up to 13729 N·m with lighter weights (340-460 kg), whereas Heavy Duty models (like HDS) are built for high-demand operations, supporting torque up to 32365 N·m and weighing up to 730 kg.
Which Kelly sizes are compatible with these Roller Kelly Bushings?
These bushings are highly versatile and accommodate both Square and Hexagonal Kelly sizes. For instance, the 20-MDP and 20-HDP models support Square Kelly sizes from 63.5 to 133.35 mm (2 1/2 to 5 1/4 in) and Hexagonal sizes from 76.2 to 107.95 mm (3 to 4 1/4 in).
How does the quad-roller design reduce friction during operations?
The quad-roller precision design features four induction-hardened rollers. This design minimizes surface contact friction, reducing overall frictional resistance by up to 68% compared to traditional solid bushings.
What drive types are available for the Medium and Heavy-Duty models?
Both Square and Pin Shaft drive configurations are available. For example, the 20-HDP (Medium) and HDS (Heavy) feature a Square drive, while the MDS (Medium) and 27-HDP (Heavy) utilize a Pin Shaft drive.
What proven operational benefits do these bushings offer in active rig environments?
Field operations, such as those in Middle Eastern rigs, show that implementing heavy-duty pin drive bushings can reduce torque fluctuations by 35% and extend the operational service life of the Kelly by up to 50%.