Riser flange bolts and nuts, ram bonnet bolts, API 6BX flange and connector studs, annular head studs and choke and kill line bolting, made in Houston to your drawings and specifications.
An 18-3/4 inch, 15,000 psi subsea blowout preventer stack on its wellhead connector, with the lower marine riser package (LMRP) on top and the first two joints of the marine drilling riser above that. It comes apart from the top down, the way it is stripped on the rig and in the shop. The buoyancy clamps come off and the modules part; at each riser flange the nuts spin off and the joint lifts, pulling its choke, kill, booster and hydraulic line stabs out. The LMRP lifts off the stack mandrel, then the flex joint, the annular head and the annular come off in turn, nuts first. The frame unbolts, the choke and kill lines and their failsafe valves come off the ram bodies, the bonnet bolts back out and the bonnets open with their rams, and the ram preventers part at their flanges down to the wellhead connector and guide funnel. The bolting we make is in colour. Press Solid view for a steel model, or Cutaway to see the bore, the ram cavities, the operators and the annular packing element in section.
Six large bolts at each riser flange, each dropping through the upper flange into a nut held under the lower one, between the choke, kill, booster and hydraulic line stabs. A set for every joint in the string.
Four bolts and nuts close each split thrust clamp round the riser pipe, above and below every pair of buoyancy modules.
Twenty-four 2-1/4 in. tap-end studs on a 36.44 in. bolt circle in the annular preventer's studded top (18-3/4 in. 10,000 psi, API 6A type 6BX), a nut on each, over a BX-164 ring gasket.
A ring of heavy studs and nuts holding the head on the annular preventer's body; off for every packing element change.
Twenty 3 in. tap-end studs on a 40 in. bolt circle in the studded 18-3/4 in. 15,000 psi top of each hydraulic connector: the LMRP connector under the annular, and the wellhead connector under the lowest ram preventer.
Eight large bolts per bonnet, ten bonnets on five ram cavities. Backed out at every ram change so the bonnet can open.
Twenty 3 in. studs at each 18-3/4 in. 15,000 psi 6BX joint, over a BX-164 ring gasket: 26-3/4 in. long with two heavy hex nuts where both sides are flanged, tap-end with one nut into a studded top.
Eight 1-1/8 in. studs on a 9.06 in. bolt circle at each 3-1/16 in. 15,000 psi 6BX flange, over a BX-154 ring gasket: tap-end studs in the ram body outlets, and 7-1/2 in. studs with two nuts where each valve meets its line.
Four bolts per two-piece clamp holding the choke and kill lines to the ram bodies and the LMRP connector.
Bolts at the beam splices and arm ends that tie the two halves of the stack frame together round the preventers.
A ring of bolts and nuts fixing the guide funnel under the wellhead connector.
Riser flange bolts, bonnet bolts and BOP flange studs and nuts, to your drawing and material spec. Send us your drawings and material spec.
Request a quote832-446-3442A generic 18-3/4 in. 15,000 psi subsea stack, not any maker's design. The body, connector and outlet flanges, their studs and their BX ring gaskets follow the API 6A type 6BX tables (18-3/4 in. 15,000 and 10,000 psi, 3-1/16 in. 15,000 psi). The riser pipe, riser flange and line sizes and the double ram preventer's height and length are published figures, used as typical. Everything else is typical: six bolts per riser flange and their size, eight bolts per ram bonnet, the annular head studs, the 10,000 psi flex joint flange, and the clamp, frame and funnel bolting. The riser joints are drawn as short 10 ft pup joints (full joints run 75 or 90 ft), and all body, connector, annular, flex joint, valve, frame, pod and buoyancy shapes are illustrative typical proportions. Your drawings govern. We manufacture to your drawings and specifications.
Drawn to API 6A (type 6BX flanges, studs and BX ring gaskets, the end connections API 16A drill-through equipment uses), with riser and ram preventer sizes from published data sheets for API 16F riser and API 16A ram preventers.
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