7 machines and machine tools, namely pumps, injectors, coiled tubing units, engines, transmissions, workover equipment, mudding equipment, cement mixers, centrifugal pumps, recirculating mixers, drills motors packers, liner hangers, landing nipples, hydraulic valves and controls, pneumatic valves and controls, wireline equipment, rotary sidewall coring equipment, blenders, sand feeders and conveyors, cementing, fracturing and acidizing tools, valve actuators, couplings, high pressure jetting apparatus, circulating tanks, dump bailers, perforators, fluid samplers, nitrogen and carbon dioxide units, filtration units, for use in well drilling and well working