End cover studs and nuts, bundle tie bolts, seal and bearing housing bolting, nozzle flange studs, coupling bolts and the bolts that hold it down, made in Houston to your drawings and specifications.
A radially split (barrel) centrifugal compressor for gas pipeline, gas processing or refinery service, with a 16-inch Class 900 suction and a 12-inch Class 900 discharge pointing down and bolted end covers, taken apart the way it is at an overhaul: the coupling guard and spacer come out, the nozzle and small-bore flanges are broken, the bearing housings and dry gas seal cartridges are drawn off the shaft ends, the head nuts spin off and the thrust-end head is drawn over its studs, then the bundle is withdrawn on its axis and opened. The drive-end head stays on. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the barrel wall, the head, the diaphragms, the impellers and the balance piston in section.
A ring of twenty-four studs is screwed into each end of the barrel, with a heavy hex nut on the head: 2-1/2 in. studs on a 44-1/2 in. circle here. API 617 calls for studs, not cap screws, on bolted end covers. The count and size are typical for a casing of this size; higher pressure casings hold the head with a shear ring instead.
Long through bolts, threaded at each end, that hold the diaphragms and the two end walls together as one bundle so the inner assembly slides out of the barrel in one piece.
Hold each dry gas seal cartridge in its bore in the head. They come out before the cartridge is drawn off the shaft.
Bolt each bearing housing to the outside of its head, over the seal.
Clamp the top cover of each bearing housing to its lower half, over the journal bearing and, at the thrust end, the thrust bearing.
Close-fitting bolts joining the spacer to the compressor and driver hubs, carrying the full drive torque.
Twenty 1-5/8 in. studs on a 24-1/4 in. bolt circle on the suction flange and twenty 1-3/8 in. studs on a 21 in. bolt circle on the discharge flange (ASME B16.5 Class 900, NPS 16 and NPS 12), each with two heavy hex nuts.
Four 7/8 in. studs on each seal gas connection (ASME B16.5 Class 900, NPS 1) and four 5/8 in. studs on each lube oil supply and drain flange (Class 150, NPS 2).
Hold the casing feet down on their pedestals, two per foot, while keys keep the casing on its centre line.
Set in sleeves in the concrete foundation with a plate and nut at the bottom, and nutted down on the skid.
Alignment screws in lugs on the pedestals that move the casing feet to line the compressor up with its driver, and levelling screws beside the anchor bolts.
Head studs and nuts, and the rest of the compressor's bolting, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic barrel compressor, not any maker's design. The suction and discharge nozzle flanges, the seal gas and lube oil flanges and their studs follow ASME B16.5. The barrel, heads, bundle, rotor, seals, bearing housings, coupling, supports, skid and foundation are illustrative typical proportions, and the head stud count and size (twenty-four 2-1/2 in. studs per head) and the other bolt counts and sizes are typical for a machine of this size, not taken from a standard. Your drawings govern. We manufacture to your drawings and specifications.
Drawn to ASME B16.5 (the Class 900 nozzle flanges, the Class 900 seal gas and Class 150 lube oil flanges, and their studs) and to API 617 practice for a radially split casing with bolted end covers (studs on the end covers, a bundle that withdraws from one end).
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