Preparing steel connection
API 11B · Steel sucker rod
Designed around the connection.
A forged rod end, precision-machined shouldered pin and matched steel coupling carry cyclic axial load through every pumping stroke.
01 · Forged end geometry
Strength begins before the thread.
The 22.23 mm rod body transitions into an enlarged forged end. Smooth upset geometry limits abrupt section changes near the wrench square and pin shoulder.
- Rod body
- 22.23 mm
- Pin shoulder
- 41.28 mm
02 · Shouldered pin
Machined as a connection system.
The male pin combines a controlled thread form with a machined shoulder. For the 7/8 in rod shown here, the representative API pin designation is 1-3/16 in.
- Pin thread
- 1-3/16 in
- Thread density
- 10 TPI
03 · Full-size coupling
Box threads move into engagement.
The coupling contains opposed internal box threads for joining adjacent rods. Its end face seats against the pin shoulder as the joint is made up.
- Full-size OD
- 46.0 mm
- Configuration
- Double box
04 · Connection engagement
Thread contact and shoulder seating.
A transparent engineering view reveals the helical engagement inside the coupling. Final field make-up must follow the applicable connection procedure rather than appearance alone.
- 01Pin and box thread compatibility
- 02Clean shoulder contact
- 03Controlled connection preload
05 · Cyclic load path
One continuous steel load path.
Axial load passes from the rod body through the forged end, pin connection and coupling body. Every pumping stroke repeats the axial stress cycle.
- Representative class
- D-family
- Tensile range
- 115–140 ksi
7/8 in · API 11B
Steel, forged for the rod string.
Connection dimensions, material class, coupling configuration and applicable API edition must be confirmed together for final supply.