Main bearing and connecting rod bolting, crosshead nuts, crosshead guide and distance piece studs, cylinder head, valve cap and flange studs, cover screws, hold-down and anchor bolts, made in Houston to your drawings and specifications.
A two-throw, horizontal balanced-opposed process compressor in the style of API 618, on its skid: 16-inch bore, 12-inch stroke double-acting cylinders, each with an NPS 8 Class 300 suction flange on top and an NPS 6 Class 300 discharge flange underneath. It comes apart the way a fitter strips it, and at each joint the nuts spin off first, then the joint opens. The piping comes off the cylinders, then the valve caps and valves, the cylinder heads, and the pistons and rods. The cylinders come off the distance pieces, the distance pieces off the crosshead guides and the guides off the frame. Last come the frame's tie rods, the connecting rod caps and the main bearing caps. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the piston, rod, packing and valves inside one cylinder.
Clamp the three main bearing caps over the crankshaft journals, four studs a cap. They carry the full crankshaft load.
Cross the open top of the frame above each main bearing, each through a spacer tube, tying the two sides of the frame together. They come out before a bearing cap can lift.
Hold each connecting rod cap round its crank-pin bearing, two a rod. Pre-stretched, and often specified with rolled threads.
Lock the piston rod into the crosshead once the piston end clearance is set, and hold the piston on the other end of the rod.
Round the frame top cover and the inspection cover on each crosshead guide.
Bolt each crosshead guide to the frame, twelve studs round the flange; they take the rod load on every stroke.
Bolt the distance piece to the crosshead guide and to the cylinder. The cylinder hangs off them.
Hold the pressure packing case in the crank end of each cylinder, round the piston rod.
Clamp the outer head onto the head end of each cylinder.
Hold the caps over the suction and discharge valves: the most often opened joints on the machine.
Bolt the suction and discharge piping or pulsation bottles to each cylinder: twelve 7/8 in. × 5-1/2 in. studs on a 13 in. bolt circle at the NPS 8 suction flange, twelve 3/4 in. × 4-3/4 in. studs on a 10-5/8 in. bolt circle at the NPS 6 discharge flange (ASME B16.5 Class 300), each with two heavy hex nuts.
Hold the frame feet and the crosshead guide support feet down on the skid pedestal.
Cast into the foundation and preloaded through the skid beams, with a plate washer and heavy hex nut on each.
Distance piece, head, valve cap and running gear bolting for your compressor, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic two-throw compressor, not any maker's design. The suction and discharge nozzle flanges and their studs follow ASME B16.5 Class 300 (NPS 8 and NPS 6). The frame, running gear, crosshead guides, distance pieces, cylinders, valves and skid are illustrative typical proportions, the distance piece access openings are drawn without their covers, and every other bolt size and count is typical. Your drawings govern. We manufacture to your drawings and specifications.
Drawn to ASME B16.5 (the Class 300 suction and discharge nozzle flanges and their studs), in the general arrangement of an API 618 process compressor.
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