Dover Artificial Lift offers two types of couplings, both of which meet API Class T and Class SM specifications.
The Norris Type T sucker rod couplings are manufactured from AISI Class A-8630 alloy special-quality, cold-drawn tubing formed to size with a material hardness of 56 to 62 HRA and magnetically inspected. Blanks are machined to coupling size and tolerance, threaded by cold forming, rolled thread tapped for thread strength and fatigue resistance, and black oxide coated for anti-galling and lubricating properties. All dimensions and tolerances conform to API Spec 11B. Type T couplings are recommended for installations with a low risk of abrasion or corrosion.
Norris Sprayloy® sucker rod couplings are manufactured from AISI Class A-8630 alloy special-quality, cold-drawn tubing and in their own dedicated line. Blanks are cleaned, prepared, loaded on mandrels, shot blasted, flame sprayed and induction fused. The complete flame spray process is a computer controlled, menu driven operation that holds spray application tolerances to within two thousandths of an inch. Sprayloy® couplings are manufactured with a 0.010" - 0.015" (0.254 mm - 0.381 mm) thick nickel-chromium coating on the O.D. These couplings are recommended for abrasion and corrosion resistance.
All couplings are manufactured in a variety of styles and in most sucker rod sizes. Couplings are available in API full-size and slimhole, and oversize couplings are available on request.
Polished rod couplings are also available in box and box styles, in all combinations of sucker rod sizes, and in full-size and slimhole outside diameters. Polished rod couplings are to be used with current API polished rods with the nine-degree cone pin.