Turbine casing studs with heater holes and their nuts, steam chest, valve and flange bolting, bearing cap studs, coupling bolts and the bolts that hold it down, made in Houston to your drawings and specifications.
A 5 MW multistage back-pressure steam turbine with a horizontally split casing, an 8-inch Class 600 steam inlet and a 24-inch Class 150 exhaust, opened up the way a fitter does it: the inlet and exhaust flanges and the coupling come apart, the joint nuts spin off and the upper casing lifts straight up on its guide rods, then the bearing caps come off and the rotor lifts out of the lower half. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the rotor, blade rows, diaphragms and shaft glands inside the casing.
Eighteen studs a side clamp the upper casing half to the lower one, each with a heavy nut on the upper flange: 2-1/2 in. at the steam end and 2 in. at the exhaust end here. Typically A193 B16, 422 stainless or a nickel alloy, bored with a heater hole so they can be heated, stretched and tightened. The count and sizes are typical for a machine of this size.
Hold the steam chest cover over the control valves, the trip and throttle valve bonnet, and the trip valve's flange to the chest.
Bolt the steam supply to the trip and throttle valve: twelve 1-1/8 in. studs on a 13-3/4 in. bolt circle (ASME B16.5 Class 600, NPS 8), each with two heavy hex nuts.
Bolt the exhaust line to the outlet flange under the lower casing half: twenty 1-1/4 in. studs on a 29-1/2 in. bolt circle (ASME B16.5 Class 150, NPS 24), each with two heavy hex nuts.
Hold the shaft seal housings on the two ends of the casing, where the rotor passes out through its labyrinth seals.
Clamp the bearing caps on the front and rear pedestals over the journal and thrust bearings. They come off before the rotor can be lifted.
Fitted bolts joining the coupling hubs and spacer, carrying the turbine's torque to the driven machine.
Hold the casing paws down on the pedestals with a set clearance, so the casing can grow as it heats.
Through bolts in sleeves in the foundation slab, with a plate and nut underneath, holding the pedestals down on their soleplates.
Levelling jackscrews in the pedestal bases, and jack bolts in the upper flange that break the casing joint before the lift.
Turbine casing studs with heater holes, and the rest of the bolting, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic 5 MW turbine, not any maker's design. The steam inlet and exhaust flanges and their studs follow ASME B16.5. The casing, rotor, steam valves, bearings, pedestals and foundation are illustrative typical proportions, and the joint stud count (eighteen a side), the joint stud sizes and the other bolt counts 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 600 inlet and Class 150 exhaust flanges and their studs) and to API 612 practice for the casing joint (studs on the main joint, jackscrews and guide rods), with the heater holes and the stretch figure for the joint studs taken from published turbine bolting practice.
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