American Certified Equipment, doing business as Valveworks USA, is a manufacturer and distributor of oil field products, gate valve parts and well-headed components. The company offers a variety of replacement parts that include hanwheel nuts, bearing retainer lock nuts, thrust bearings, packing fittings, bonnet grease fittings, seat assembly, bonnet and stud nuts, and rising and nonrising stems. Its well-headed components include flanges, adapters and tube heads. It also provides service manuals and trim charts. Its machinery capabilities include horizontal mills, punch presses, surface grinders and drill presses. It provides a variety of valves, including threaded, ball, flanged and segmented gate. It is located in Shreveport, La.