Precision Spacing Components for Casing, Tubing & Drill Strings
Pup joints are short sections of pipe used to achieve exact spacing, positioning, and length adjustment in casing strings, tubing strings, drill strings, and completion assemblies. They are manufactured from the same material grade, wall thickness, and heat treatment condition as the parent pipe, ensuring full mechanical and metallurgical compatibility throughout the string.
A pup joint is not an “offcut.” It is a deliberately manufactured product with full traceability to heat number, certified MTRs, and dimensional inspection per API 5CT. In critical wells—HPHT, deepwater, sour service—the failure of a single pup joint due to incorrect material or thread tolerances can compromise the entire well barrier.
Why Pup Joints Are Critical
| Function | Operational Impact |
|---|---|
| Spacing Out Casing & Tubing Strings | Positions downhole equipment (packers, nipples, sliding sleeves, SSSVs) at the exact depth required. Without pup joints, tools would be meters off-target. |
| Tally Adjustment | Casing and tubing runs never match the theoretical design exactly. Pup joints compensate for accumulated thread makeup loss, casing stretch, and measurement variations. |
| BHA Spacing | Positions stabilizers, jars, and MWD tools at precise distances from the bit for directional control. |
| Surface Wellhead Adjustment | Achieves correct stick-up height above the wellhead for Christmas tree installation. |
| Repair of Damaged Threads | When a pin or box end is damaged during running, the joint is cut off and a pup joint is made up to salvage the remaining pipe. |
Pup Joint Types by Application
Casing Pup Joints
Used in the casing string to adjust spacing between casing collars, centralizers, and float equipment.
| Parameter | Specification |
|---|---|
| Standard | API 5CT |
| OD Range | 4-1/2″ to 20″ |
| Wall Thickness | Matches parent casing (e.g., 32.00 lb/ft, 47.00 lb/ft) |
| Grades | Same as parent pipe: J55, K55, N80, L80, P110, C95, T95, Q125 |
| End Connections | STC, LTC, BTC, Extreme-Line, Premium (matched to string) |
| Typical Lengths | 2 ft, 4 ft, 6 ft, 8 ft, 10 ft, 12 ft, 15 ft (custom available) |
| Makeup | Pin x Box (male thread one end, female coupling other end) or Pin x Pin (coupling supplied separately) |
Special Requirements:
- Sour Service: HIC and SSC tested per NACE MR0175
- High Collapse: Enhanced collapse resistance matching heavy-wall casing
- Thermal Wells: High-temperature grade retention per material class
Tubing Pup Joints
Used in the tubing string to position downhole flow control devices at precise depths.
| Parameter | Specification |
|---|---|
| Standard | API 5CT |
| OD Range | 1.050″ to 4-1/2″ |
| Wall Thickness | Matches parent tubing |
| Grades | J55, L80, N80, P110, L80 13Cr, Super 13Cr, Duplex |
| End Connections | NU, EU, IJ, Premium (matched to string) |
| Typical Lengths | 1 ft, 2 ft, 3 ft, 4 ft, 6 ft, 8 ft, 10 ft |
Critical Applications:
- Landing nipple positioning for SSSV installation
- Gas lift mandrel spacing
- Sliding sleeve depth alignment
- Chemical injection mandrel placement
- Packer setting depth adjustment
Drill Pipe Pup Joints
Used in the bottomhole assembly (BHA) for precise spacing of downhole tools.
| Parameter | Specification |
|---|---|
| Standard | API 5DP, DS-1 |
| OD Range | 2-3/8″ to 6-5/8″ |
| Grades | E-75, X-95, G-105, S-135 |
| Tool Joints | NC26, NC31, NC38, NC40, NC46, NC50, 5-1/2 FH |
| Typical Lengths | 5 ft, 10 ft, 15 ft |
| Features | Hardbanding optional. Internal plastic coating optional |
Pup Joint vs. Saver Sub
| Component | Function | Location |
|---|---|---|
| Pup Joint | Spacing and length adjustment in the string | Anywhere in casing, tubing, or drill string |
| Saver Sub | Sacrificial connection that protects the bottom thread of a motor, MWD, or drill collar | At the bottom of the BHA, above the bit |
Manufacturing & Quality Requirements
Pup joints are not simply cut from rejected full-length pipe. Reputable manufacturers produce them from the same prime-grade pipe with full traceability.
| Requirement | Description |
|---|---|
| Material Identity | Must match the heat number and material test report of the parent pipe or be manufactured from same-grade billet with full MTR |
| Heat Treatment | Same as parent pipe grade (normalized, normalized & tempered, quenched & tempered as specified) |
| Threading | Cut to same API or premium thread specifications as main string |
| Drift Testing | Full-length drift mandrel per API 5CT to verify minimum ID |
| Hydrostatic Testing | Same test pressure as parent pipe |
| NDE | Magnetic particle or liquid penetrant inspection of threads. Ultrasonic testing of pipe body if specified |
| Traceability | Each pup joint stamped with heat number, grade, OD, wall thickness, and unique serial number |
| Coupling Makeup | Bucked-on to specified torque per API RP 5C1 or premium connection procedure |
| Thread Protection | Steel or composite thread protectors on pin and box ends |
Pup Joint Material Options
| Service Condition | Material Grade | NACE MR0175 | Typical Lengths Required |
|---|---|---|---|
| Sweet shallow wells | J55, K55 | No | 2 ft, 4 ft, 6 ft |
| Sweet intermediate depth | N80 | No | 4 ft, 6 ft, 10 ft |
| Sour gas production | L80 Type 1, C90, T95 | Yes | 2 ft, 4 ft, 6 ft, 10 ft |
| High pressure deep wells | P110, Q125 | No (unless qualified) | 4 ft, 6 ft, 10 ft |
| CO2-rich gas | L80 13Cr, Super 13Cr | Limited H2S | 4 ft, 6 ft, 10 ft |
| HPHT sour | Duplex 22Cr, 25Cr | Yes | 2 ft, 4 ft, 6 ft |
| Thermal (steam injection) | Special thermal grades (proprietary) | Sometimes | Custom lengths per design |
Operational Best Practices
| Practice | Importance |
|---|---|
| Order with the main string | Avoids last-minute shortages. Add 5-10% to theoretical pup joint count for contingencies |
| Verify thread compatibility | Premium connections must match exactly (VAM TOP, TenarisHydril Blue, etc.). Mixing brands will cause leaks |
| Check drift | Always drift pup joints on the rig floor before running to ensure no internal obstruction |
| Match material grade | A lower-grade pup joint in a high-strength string is a failure point. Never mix grades |
| Inspect threads visually | Thread damage during transport is common. Inspect and recut if needed before running |
Pup Joint Supply Chain Considerations
Pup joints are high-frequency, small-quantity items. Procurement managers often underestimate lead times because the part “seems simple.” In reality:
- Premium thread pup joints can have the same lead time as the main pipe (weeks to months) due to threading shop backlogs
- Sour service grades require additional HIC/SSC testing time
- Short lengths are more expensive per foot than full-length pipe due to handling and threading costs
- Expedited delivery is often required when a string runs short during installation
We recommend ordering pup joints concurrently with the main casing or tubing order to ensure matching heat numbers, identical material properties, and on-time availability.
How We Support Your Pup Joint Requirements
- Full Traceability: Every pup joint delivered with original MTRs matching your main string
- Premium Compatibility: Threading matched exactly to your specified premium connection (VAM, TenarisHydril, Hunting, TSH, JFE)
- Sour Service Assurance: HIC/SSC certification per NACE MR0175 supplied with each joint
- Emergency Supply: Access to pup joint inventory and quick-turn threading shops for last-minute rig needs
- Kitting: Pup joints supplied as part of a complete casing or tubing package with all accessories