Bottom and top unheading valve studs and nuts, valve bonnet bolting, vapour line, feed inlet and nozzle flange studs, and skirt anchor bolts, made in Houston to your drawings and specifications.
A delayed coker coke drum on its skirt: 28 feet inside diameter, with a 60-inch bottom outlet under the cone and a 30-inch outlet on the top head (the straight shell is drawn shortened to 40 feet so the whole drum fits the screen). It comes apart the way a turnaround crew does it: the nozzle flange nuts spin off and the vapour, relief, feed and steam piping clears, the cutting-tool enclosure and the top unheading valve lift off, the chute spool drops, the bottom flange is unbolted and the inlet spool and unheading valve are lowered, the valve bonnets are drawn back, and the drum lifts off its anchor bolts. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the shell and cone wall and the gate and seats inside both valves.
Thirty-two 2-1/4 in. × 18-1/2 in. studs on a 67 in. bolt circle at each of two joints: the feed inlet spool to the 60-inch flange under the cone, and the bottom unheading valve to the spool (drawn to ASME B16.47 Series A Class 300, NPS 60). They heat to coking temperature and cool again on every drum cycle.
Thirty-two studs of the same size bolt the transition spool under the unheading valve, leading the cut coke into the chute.
Twenty-eight 1-3/4 in. × 12 in. studs on a 39-1/4 in. bolt circle at each of two joints: the top unheading valve to the 30-inch flange on the top head, and the cutting-tool enclosure to the valve (drawn to ASME B16.47 Series A Class 300, NPS 30).
Studs and nuts round the rectangular bonnet joints of both unheading valves, shown at 1-1/2 in. on the bottom valve and 1 in. on the top valve. Sizes and counts are typical; the valve drawing governs.
Twenty-four 1-1/2 in. × 9 in. studs on the 24-inch vapour outlet on the top head (ASME B16.5 Class 300).
Twelve 7/8 in. × 5-1/2 in. studs on the 8-inch side-entry feed nozzle on the inlet spool (ASME B16.5 Class 300).
The 8-inch relief connection and two 2-inch instrument nozzles on the top head, and the 4-inch steam and quench water connection on the inlet spool, all ASME B16.5 Class 300.
Thirty-six anchor bolts cast into the concrete deck and up through the base ring and anchor chairs, each with a washer and heavy hex nut. Shown at 2-1/2 in.; the structural design sets the size and count.
Unheading valve studs, nozzle flange bolting and anchor bolts for coke drums, to your drawing. Send us your drawings and material spec.
Request a quote832-446-3442A generic 28 ft coke drum, not any maker's or licensor's design, with the straight shell drawn shortened. The 60-inch and 30-inch flanges and their studs are drawn to ASME B16.47 Series A Class 300, and the nozzle flanges, studs and gaskets to ASME B16.5 and B16.20 Class 300; real drum and unheading valve flanges are often purpose-designed. The drum size, plate thicknesses, cone, skirt, anchor chairs, deck, both slide valves, the inlet and chute spools, the cutting-tool enclosure and the nozzle sizes and positions are illustrative typical proportions; the bonnet bolting and anchor bolt sizes and counts, and all bolting materials, are typical. Your drawings govern. We manufacture to your drawings and specifications.
Drawn to ASME B16.47 Series A (Class 300 flanges and stud bolts for the 60-inch and 30-inch joints) and ASME B16.5 with ASME B16.20 gaskets (Class 300 nozzle flanges); the bolting materials are named to ASTM A193, A194 and F1554.
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