Sucker Rod Couplings
API 11B sucker rod couplings, also known as rod boxes, in 5/8" to 1" rod sizes. Class T and Spray Metal, in Full Size and Slim Hole.
About Sucker Rod Couplings (Rod Boxes)
Trilogy sucker rod couplings join the pin ends of adjacent sucker rods in rod-pumped wells and carry the cyclic loads of the pumping string. They are made from AISI 5140 alloy steel to API Specification 11B dimensions and are marked with rod size, class and date code.
Class T couplings are through-hardened for general rod string service and are the standard choice for most wells. Spray Metal couplings add a hard, thermally sprayed surface for wear resistance where couplings contact the tubing, such as in deviated wells. Full Size and Slim Hole ODs suit your tubing clearance, and change-over couplings join two rod sizes in a tapered string.
Specifications at a Glance
Standard Couplings
| Part No. | Rod Size | Type | Class | OD |
|---|---|---|---|---|
| T-RC58FST | 5/8" | Full Size | Class T | 1.500" |
| T-58SHT | 5/8" | Slim Hole | Class T | 1.252" |
| T-RC34FST | 3/4" | Full Size | Class T | 1.625" |
| T-RC34SHT | 3/4" | Slim Hole | Class T | 1.500" |
| T-RC34FSSM | 3/4" | Full Size | Spray Metal | 1.625" |
| T-34SHSM | 3/4" | Slim Hole | Spray Metal | 1.500" |
| T-RC78FST | 7/8" | Full Size | Class T | 1.811" |
| T-RC78SHT | 7/8" | Slim Hole | Class T | 1.626" |
| T-RC78FSSM | 7/8" | Full Size | Spray Metal | 1.811" |
| T-RC78SHSM | 7/8" | Slim Hole | Spray Metal | 1.626" |
| T-RC1SHT | 1" | Slim Hole | Class T | 2.000" |
All couplings 4.000" minimum length, box thread both ends. Material: AISI 5140 alloy steel to API Spec 11B.
Change-Over (Sub) Couplings
| Part No. | Rod Sizes | Type | Class | OD |
|---|---|---|---|---|
| T-34X58FST | 3/4" x 5/8" | Full Size | Class T | 1.625" |
| T-34x78FST | 7/8" x 3/4" | Full Size | Class T | 1.811" |
| T-34x78FSSM | 7/8" x 3/4" | Full Size | Spray Metal | 1.811" |
| T-34x78SH | 7/8" x 3/4" | Slim Hole | Class T | 1.626" |
| T-34x78SHSM | 7/8" x 3/4" | Slim Hole | Spray Metal | 1.626" |
Change-over couplings connect two rod sizes in a tapered string. OD follows the larger rod size.
Get the Right Part the First Time
Sizes and configurations vary by application. Send us the details below and our team will confirm the spec, check stock and come back with a firm quote.
Start a QuoteWhat to Include in Your Request
- Part number or rod size
- Full Size or Slim Hole
- Class T or Spray Metal
- Quantity
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