API 5/8 FS Class SM Sucker Rod CouplingS

T and SM grades of Sucker Rod Couplings. Both grades are manufactured with cold worked pre-stressed, roll-formed threads. This round root form is substantially stronger and provides better fatigue resistance than conventional cut threads. The threads of both grades of couplings are coated for anti-galling properties.

Dimensions, tolerances, and manufacturing inspection of these couplings conform to or exceed the requirements of the latest edition of API Spec. 11B. All grades of coupling are available in API full or slimhole diameters.

Grade T Sucker Rod Couplings

These API Class T couplings are made of 4135 alloy steel and offer excellent resistance to hydrogen embrittlement. They are furnished with all Weatherford sucker rods unless otherwise specified.

Grade SM CO-HARD Sucker Rod Couplings

These couplings are made of 4135 alloy steel and offer excellent resistance to hydrogen embrittlement. The base metal is prepared to a No. 1 finish per NACE TM0170 or TM0175 before spray weld coating is applied. This provides a strong metallurgical bond between base metal and the spray metal coating.

CO-HARD couplings incorporate a spray weld coating for maximum corrosion/abrasion resistance to hydrogen embrittlement. They are intended for use with rods where coupling abrasion wear or coupling corrosion is a problem.

Mechanical Properties

Tensile 100,000 psi (min) Hardness 56-62 HRA SM Coating Thickness 0.010” to 0.020 “ SM Coating Hardness 595 HV₂₀₀(min)