Drill collar slips are among the most important pieces of manual handling equipment used on the rig floor. Designed to safely suspend the weight of the drill collar string in the rotary table, they allow crews to make and break drill string connections during drilling, tripping and well servicing operations.
Although drill collar slips may appear simple, selecting the correct model is critical for both safety and operational efficiency. The wrong slip size can lead to poor gripping performance, accelerated insert wear and, in severe cases, damage to expensive drill collars.
This guide explains everything you need to know about API 7K Drill Collar Slips, including how they work, the differences between DCS-S, DCS-R and DCS-L models, how to select the correct size, inspection and maintenance recommendations, and the spare parts available to keep your equipment operating safely.
What Are Drill Collar Slips?
Drill collar slips are manually operated handling tools designed to grip and suspend drill collars while they are supported by the rotary table. Unlike rotary slips used for drill pipe, drill collar slips are designed specifically for the larger outside diameters and greater loads associated with drill collars.
Each slip consists of several precision-machined steel segments fitted with replaceable circular button inserts. When lowered into the tapered insert bowl of the rotary table, the slips are forced inward by the taper, allowing the button inserts to securely grip the drill collar.
The load is transferred from the drill collar, through the slips and insert bowl, into the rotary table and ultimately to the rig structure.
How Do Drill Collar Slips Work?
Drill collar slips operate using the standard API taper of 4 inches per foot.
As the slips are lowered into the rotary table insert bowl, the tapered surfaces force each segment towards the centre of the drill collar. The circular button inserts bite into the outer surface of the collar, distributing the load evenly around its circumference.
The larger the suspended load, the greater the gripping force created by the tapered interface.
This simple yet highly effective design has been the industry standard for decades.
Types of Drill Collar Slips
API-style Drill Collar Slips are available in three standard configurations.
DCS-S (Short)
The Short model is designed for smaller drill collars ranging from 3" to 4 7/8" OD.
Its compact design provides excellent handling while maintaining secure gripping performance.
DCS-R (Regular)
The Regular model is suitable for 4 1/2" to 7" drill collars.
It provides additional gripping length and is commonly used on most land and offshore drilling rigs.
DCS-L (Long)
The Long model is intended for large drill collars from 6 3/4" to 14" OD.
These slips feature additional gripping area and larger segment assemblies to safely support heavier tubular loads.
The largest DCS-L models are fitted with four handles to assist operators when installing and removing the slips.
Choosing the Correct Drill Collar Slip
Selecting the correct drill collar slip depends on several factors.
Always consider:
- Drill collar outside diameter
- Slip size range
- Rotary table insert bowl number
- Total suspended load
- Rig manufacturer's recommendations
Never attempt to use drill collar slips outside their specified operating range.
Drill Collar Slip Size Chart
| Specification | 3" – 4" | 4" – 4 7/8" | 4 1/2" – 6" | 5 1/2" – 7" | 6 3/4" – 8 1/4" |
| Model | DCS-S | DCS-S | DCS-R | DCS-R | DCS-L |
| PN: Complete | 20201 | 20202 | 20203 | 20204 | 20205 |
| Grip Length | Short | Short | Regular | Regular | Long |
| Weight (kg) | 51 | 47 | 54 | 51 | 70 |
| Total Segments | 7 | 7 | 9 | 9 | 11 |
| Intermediate Segments | 5 | 5 | 7 | 7 | 9 |
| Hinge Pins | 6 | 6 | 8 | 8 | 10 |
| Insert Bowl | No.3 | No.3 | No.3 | No.3 | No.3 |
| Die | 20228-49 | 20220-49 | 20228-63 | 20220-63 | 20230-88 |
| Specification | 8" – 9 1/2" | 8 1/2" – 10" | 9 1/4" – 11 1/4" | 11" – 12 3/4" | 12" – 14" |
| Model | DCS-L | DCS-L | DCS-L | DCS-L | DCS-L |
| PN: Complete | 20206 | 20207 | 20208 | 20209 | 20210 |
| Grip Length | Long | Long | Long | Long | Long |
| Weight (kg) | 78 | 84 | 90 | 96 | 94 |
| Total Segments | 12 | 13 | 14 | 17 | 17 |
| Intermediate Segments | 10 | 11 | 12 | 15 | 15 |
| Hinge Pins | 11 | 12 | 13 | 16 | 16 |
| Insert Bowl | No.3 | No.2 | No.1 | No.1 | No.1 |
| Die | 20230-96 | 20227-104 | 20230-112 | 20225-136 | 20230-136 |
API Insert Bowl Compatibility
Drill Collar Slips are designed for use with standard API insert bowls.
| Insert Bowl | Typical Applications |
|---|---|
| API No. 3 | Smaller and medium drill collars |
| API No. 2 | Large drill collars |
| API No. 1 | Extra-large drill collars |
Always verify bowl compatibility before use.
Circular Button Inserts
Circular button inserts are the primary wear component of every Drill Collar Slip.
Manufactured from hardened alloy steel, these inserts provide the gripping force necessary to safely suspend the drill collar.
Because button inserts experience continual wear, they should be inspected before each use and replaced when worn, chipped or damaged.
Replacing inserts before excessive wear occurs helps:
- Maintain consistent gripping performance
- Reduce marking of drill collars
- Extend slip body life
- Improve rig floor safety
- Reduce maintenance costs
Safety Shark supplies replacement button inserts for all Drill Collar Slip models.
Spare Parts & Replacement Components
Routine maintenance helps maximise equipment life while reducing operational downtime.
Safety Shark supplies a complete range of replacement parts including:
- Circular Button Inserts
- Slip Segments
- Hinge Pins
- Handle Pins
- Handles
- Retaining Pins
- Hardware Kits
Using genuine replacement parts helps maintain correct fitment and compatibility with API-style Drill Collar Slips.
Common Spare Parts
Many spare parts are common across multiple Drill Collar Slip sizes.
Keeping replacement components in stock allows repairs to be completed quickly during routine maintenance or unexpected breakdowns.
Spare Parts List |
PAN-DCS-S |
PAN-DCS-R |
PAN-DCS-L |
| Segment – Right End | 20212 | 20237 | 20241 |
| Segment-Left End | 20213 | 20238 | 20242 |
| Segment-Intermediate | 20214 | 20239 | 20243 |
| Hinge Pin with Cotter Pin | 20215 | 20240 | 20244 |
| Handle Pin with Washer & Cotter Pin | 20216 | ||
| Handle for Right & Left End Segment | 20217 | ||
| Handle for Intermediate Segments | 20218 | ||
| Retaining Cotter Pin | 20235 | ||
| Retaining Screw with Lock Washer | 20236 |
Inspection & Maintenance
Drill Collar Slips should be visually inspected before every use and maintained in accordance with your company's maintenance procedures and the manufacturer's recommendations.
Routine inspections should include checking:
- Slip bodies
- Taper surfaces
- Button inserts
- Hinge pins
- Handles
- Retaining hardware
- Identification markings
Remove any damaged equipment from service immediately.
For detailed inspection procedures, maintenance schedules and recommended acceptance criteria, refer to the Safety Shark Handling Equipment Inspection & Maintenance Guide (Appendix A).
Frequently Asked Questions
What is the difference between Drill Pipe Slips and Drill Collar Slips?
Drill Pipe Slips are designed for drill pipe and tubing, while Drill Collar Slips are engineered to handle the larger outside diameters and significantly heavier loads associated with drill collars.
What do DCS-S, DCS-R and DCS-L mean?
- DCS-S – Short
- DCS-R – Regular
- DCS-L – Long
Each model covers a different range of drill collar sizes.
Can button inserts be replaced?
Yes.
Circular button inserts are replaceable and should be changed whenever excessive wear or damage is observed.
Are Drill Collar Slips API 7K compliant?
Safety Shark Drill Collar Slips are manufactured to an API 7K style design and are compatible with standard API insert bowls used throughout the drilling industry.
Related Products
Complete your rig floor handling equipment with:
- Rotary Drill Pipe Slips
- Casing Slips
- Safety Clamps
- Slip Bowls
- Circular Button Inserts
- Rotary Slip Spare Parts
- Casing Slip Spare Parts
Conclusion
Drill Collar Slips are a critical component of safe and efficient rig floor operations. Selecting the correct model, maintaining button inserts and following a regular inspection program will help maximise equipment life while reducing operational risk.
Safety Shark supplies a complete range of API 7K-style Drill Collar Slips, replacement button inserts and spare parts for drilling contractors operating in oil & gas, geothermal, mining and water well industries.
Browse our complete range of Drill Collar Slips or contact the Safety Shark team for assistance selecting the correct model for your drilling operation.