Drum manway studs, safety valve and instrument flange studs, harp hanger rods, casing, duct and stack flange bolts, column splice bolts and anchor bolts, made in Houston to your drawings and specifications.
A horizontal-gas-flow, vertical-tube heat recovery steam generator behind a gas turbine, with a 60 in. high-pressure steam drum, drawn as a representative, shortened unit and opened up the way an outage goes. The drum manway nuts and yokes come off and the covers swing in; the safety valves, water column and instrument flanges come off; the cyclone separators and dryers are unbolted and passed out through the manways; the access doors come off; the expansion joint, the ducts and the casing modules part at their flanges; a roof panel lifts and two harps come up on their hanger rods; the stack cans part; then the column splices and the anchor bolts. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the harps and hanger rods inside the casing and the separators and dryers inside the drum.
Each 12 in. by 16 in. elliptical manway cover seats from inside the drum and is pulled up to its gasket by two studs through two yokes. The nuts come off at every outage.
Eight 1-1/8 in. studs on an 8 in. bolt circle at each inlet flange (ASME B16.5 Class 1500, NPS 3) and twelve 3/4 in. studs at each outlet flange (Class 300, NPS 6), each with two heavy hex nuts. Typically A193 B7 or B16 with A194 2H or 4 nuts.
Eight 7/8 in. studs on a 6-1/2 in. bolt circle at each joint (ASME B16.5 Class 1500, NPS 2): the two water column connections on the drum head and the instrument nozzles on top.
Hold the cyclone separators to the baffle and the dryer boxes to their support bars inside the drum. Counts and sizes are typical.
Hold the two drum saddles to the support steel. One saddle is fixed; the other is slotted so the drum can grow as it heats.
Each harp of finned tubes hangs from the roof steel on threaded rods, with spherical washers under the nuts so a rod can tilt as the tubes grow.
Bolt the casing modules to each other round their end flanges and hold the roof panels down.
Hold the insulated access doors on their frames in the casing wall.
Bolt the expansion joint between the gas turbine exhaust and the inlet duct.
Bolt the inlet duct to the first casing module, the outlet duct to the last, and the outlet duct to the stack breeching.
Bolt the stack cans to each other through their ring flanges.
Bolt the damper between the stack cans and hold its shaft bearings.
High-strength structural bolts (ASTM F3125 Grade A325, heavy hex, with A563 DH nuts and F436 washers) through the column splice plates and the roof girder seats.
Cast into the foundations and up through the column base plates and the stack base ring.
HRSG drum, hanger, casing, duct and stack bolting, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic, representative heat recovery steam generator, not any maker's design and much shortened: a real unit has more casing modules and far taller tubes and stack. The safety valve, water column and instrument flanges and their studs follow ASME B16.5, and the manway opening is the 12 in. by 16 in. boiler manhole of ASME Section I. The drum, its internals, the valves, harps, casing, liner, ducts, expansion joint, stack, damper, steelwork, platform and foundations are illustrative typical proportions, and every other bolt count and size is typical, not taken from a standard. Bolting materials are typical choices. Piping, burners, catalyst and most platforms are not drawn. Your drawings govern. We manufacture to your drawings and specifications.
The safety valve, water column and instrument flanges and their studs are drawn to ASME B16.5 (Class 1500 and Class 300); the drum manway is the 12 in. by 16 in. elliptical boiler manhole of ASME Section I; structural bolts are named to ASTM F3125 Grade A325 and high-temperature bolting to ASTM A193 and A194 as typical choices; the layout follows published descriptions of top-supported horizontal HRSGs.
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