Stay rods, nuts and the bolts that hold the power end together, made in Houston to your drawings and specifications.
A 2,500 hp quintuplex well-service pump with an 8-inch stroke and 4-1/2 inch plungers, taken apart the way a fitter does it: the plunger clamps open, the discharge flanges and suction manifold come off, the stay rod nuts spin off and the fluid end slides forward off its twenty stay rods. Then the fluid end is stripped and the power end is opened up, down to the crankshaft and connecting rods. Everything we make is in colour. Press Solid view for a steel model, or Cutaway to see the plunger, packing and valves inside the fluid end.
Twenty two-piece stay rods with a 1-3/4 in.-8UN thread at each end. Each rod threads into the power end nose plate and runs through a sleeve that spaces the fluid end off the power end.
Twenty 1-3/4 in. heavy hex nuts, 2-3/4 in. across flats, clamping the fluid end mounting flange onto the stay rods.
Five threaded nuts in the back of the fluid end, one round each 4-1/2 in. plunger, holding the packing in place.
Ten threaded nuts holding the covers in: five suction covers in the front and five discharge covers in the top.
1 in.-8UN studs threaded into each end of the fluid end, with heavy hex nuts, holding the two discharge flanges on.
7/8 in.-9UNC hex cap screws holding the suction manifold to the bottom of the fluid end.
Four 1 in.-8UN cap screws per rod, clamping the rod cap and crank-pin bearing.
3/4 in.-10UNC cap screws bolting each pony rod flange to its crosshead.
Two 1/2 in.-13UNC socket head cap screws per clamp; out and back in at every plunger or packing change.
1/2 in.-13UNC Grade 8 cap screws holding the bearing retainer plate on the side of the frame.
Mount the planetary gearbox to the frame and close its end cover.
Crankcase top cover, crosshead inspection covers, rear cover and the oil seal housings round each pony rod.
Stay rods, nuts and power end bolting, made in Houston. Send us your drawings and material spec.
Request a quote832-446-3442A generic 2,500 hp quintuplex pump, not any maker's design. The rating, stroke, overall size and the thread sizes of the stay rods, nuts, studs and cap screws follow published pump data, and the heavy hex nuts follow ASME B18.2.2. The frame, fluid end block, valves, gearbox and covers are illustrative, and the bolt counts marked typical are typical. Your pump's drawings govern. We manufacture to your drawings and specifications.
Drawn to the published rating, overall size and fastener thread sizes of 2,500 hp quintuplex well-service pumps, with heavy hex nuts to ASME B18.2.2 and the suction manifold pipe to ASME B36.10M.
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