Manway yoke studs, drum internals bolting, safety valve and instrument flange studs, handhole studs, valve bonnet studs and hanger rod hardware are the kinds of parts we make in Houston, to your drawings and specifications.
The top of a coal-fired utility boiler: a 66 inch inside diameter steam drum hung in U-rods from the top steel, with an elliptical manway in each head, three safety valves, level instruments, vent and blowdown valves, and a superheater outlet header with its handholes and stop valve in front. The drum is welded, so it is opened the way an outage opens it: the manway yoke nuts spin off and the covers swing inward, the internals are unbolted and a scrubber basket and two cyclone separators are passed out through the manway, the safety valves and instruments come off their flanges, the handhole plugs are freed, the stop valve bonnet lifts, and last the hanger hardware is shown slackened and parted. The bolting is in colour. Press Solid view for a steel model, or Cutaway to see the cyclones, scrubbers and baffles inside the drum and a handhole fitting in section.
Two studs fixed in each inward-opening manway cover, with a yoke and nut on each outside the 12 in. × 16 in. elliptical opening. Shown at 1-1/4 in.; typical.
Four bolts hold each cyclone steam separator to its inlet duct on the girth baffle. Thirty-two cyclones are drawn; count and size are typical.
Hang the scrubber (dryer) baskets under the dry pan at the top of the drum. Nine baskets are drawn, four bolts each; typical.
Eight 1-1/4 in. × 8-3/4 in. studs on a 9 in. bolt circle hold each safety valve on its nozzle (ASME B16.5 Class 2500, NPS 3, raised face), each with two heavy hex nuts. Twelve 3/4 in. studs hold the discharge elbow on the valve outlet.
Four 7/8 in. × 5-1/2 in. studs at each steam and water connection of the level gauge and the remote level standpipe, shown as Class 2500 NPS 1.
Eight 1 in. × 7 in. studs at each end flange, shown as Class 2500 NPS 2, and six bonnet studs per valve (typical).
One stud, yoke and nut pull each elliptical handhole plug onto its seat from inside the header. Four fittings are drawn; size is typical.
Twelve bonnet studs (typical) and twelve 2 in. × 15 in. studs per end flange, shown as Class 2500 NPS 8.
Two nuts and a spherical washer set on each end of the U-rods that carry the drum from the top steel. Shown on 3 in. rod; typical.
Threaded rods from the top steel with two nuts above and a clevis pin at the header lug. Shown at 2 in.; typical.
Clip bolts through slotted holes hold the buckstay to the tie bar on the water wall, and pins link it at the corners. Typical.
Manway, safety valve, handhole and hanger bolting, made to your drawings and specifications. Send us your drawings and material spec.
Request a quote832-446-3442A generic boiler top, not any maker's or any station's design. The safety valve inlet flanges and their studs follow ASME B16.5 Class 2500 NPS 3; the stud sizes and lengths of the other flanged joints follow ASME B16.5 for the sizes shown; the manway is the 12 in. × 16 in. elliptical opening of ASME Section I. The drum is shortened (a real drum is several times longer), and its wall, heads, internals, valves, nozzles, header, handhole fittings, hangers, top steel, water wall and buckstay are illustrative typical proportions; all counts not named above, the sizes of the manway, internals, handhole, bonnet, hanger and buckstay hardware, and all bolting materials (ASTM A193 B7 or B16 studs with A194 2H, 4 or 7 nuts) are typical. Main steam stop valves on large units are usually welded in; a flanged valve is drawn to show the bolting. Your drawings govern. We manufacture to your drawings and specifications.
Flanges, studs and nuts on the safety valve inlets are drawn to ASME B16.5 Class 2500; the other flanged joints use ASME B16.5 stud sizes and lengths; the manway is the 12 in. × 16 in. elliptical opening of ASME Section I. Everything else is typical.
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