The couplings are made in full accordance with API SPEC 11B. The thread is made by tap, the basic material is round bar steel.

API 7/8” Class T Full Size Sucker Rod Coupling

1)Material: Seamless Alloy Steel 40Cr (AISI 5140) 2)Standard: API Spec 11B  3)Specification:   OD:1-13/16" (46.04mm)   ID: 1-3/16"(30.16mm)   Length: 4" (101.6mm)   Weight: 0.74kg4)Other Size: 5/8”; 3/4”;1”; 1-1/8"5)Features: The Class T coupling is manufactured with a through hardness of between 16 and 23 Rc. This result in high tensile and fatigue strengh for the coupling. The outside diameter is smooth to minimize stress concerntrations, and an accurate chamfer allows for controlled contact stress. The threads are rolled full form which results in compressive stresses at the thread root and improved fatigue resistance.

API 7/8” Class T Slim Hole Sucker Rod Coupling

1)Material: Seamless Alloy Steel 40Cr (AISI 5140) 2)Standard: API Spec 11B  3)Specification:    OD:1-5/8" (41.30mm)    ID: 1-3/16"(30.16mm)    Length: 4" (101.6mm)    Weight: 0.52kg4)Other Size: 5/8”; 3/4”;1”; 1-1/8”5)Features: The Class T coupling is manufactured with a through hardness of between 16 and 23 Rc. This result in high tensile and fatigue strengh for the coupling. The outside diameter is smooth to minimize stress concerntrations, and an accurate chamfer allows for controlled contact stress. The threads are rolled full form which results in compressive stresses at the thread root and improved fatigue resistance.

API sucker rod couplings, class SM