Subsea & Offshore fasteners & bolting.
Corrosion-resistant studs, nuts and bolting for subsea trees, manifolds, risers and offshore rigs.
Subsea and offshore bolting sits in seawater for years and has to come apart when the job calls for it: tree and manifold flange studs, riser flange bolts, BOP bonnet bolts, and tommy-bar nuts for make-up by diver or ROV. We manufacture them to your drawings and specifications in alloy steel, duplex, super duplex and nickel alloys, with full material certification.
See where the bolts go.
Subsea Production Tree
Tree cap, choke bonnet, valve bonnet, wing and outlet flange and connector body studs and nuts, plus jumper flange studs and tommy-bar nuts, actuator mounting screws, control module base bolts, ROV panel screws, frame bolts, guide funnel bolts and nuts, anode bolts and lifting pad-eye pins.
Fixed Offshore Platform
Riser clamp and riser-top flange studs and nuts, plus J-tube and caisson clamp studs, boat landing shock-cell bolts, barge bumper clamp studs, stair and handrail bolts, grating clips and bolts, wellhead and tree flange studs, conductor guide frame and hatch bolts, equipment skid hold-down bolts, crane slewing-ring bolts and flare boom splice and base bolts.
Subsea BOP Stack & Riser
Flex joint flange, annular head, connector, body flange and outlet and line flange studs and nuts, plus riser flange bolts and nuts, buoyancy clamp bolts and nuts, ram bonnet bolts, line clamp bolts, frame bolts and guide funnel bolts and nuts.
Jackup Rig Jacking System
Hold-down clamp studs and nuts, jacking gearbox mounting bolts, motor and brake mounting bolts, pinion bearing cap bolts, leg guide wear plate screws, rack chock retainer bolts, rack chock screw jacks, jack house structural bolts, access cover bolts, skid cylinder pins and keepers, crane slew ring bolts and nuts, pedestal flange bolts, raw water tower and hose rack bolts and helideck and stair tower bolts.
Subsea Manifold
Hub clamp, valve flange, valve bonnet and gear operator studs and nuts, plus clamp drive screws and trunnion nuts, clamp hinge pins, protection roof bolts, mudmat bolts, ROV panel cap screws, anode bolts and lifting shackle pins.
Offshore Crane
Slew bearing to pedestal and slew bearing to house studs and nuts, plus slew drive mounting bolts, hoist winch foot bolts, luffing winch foot bolts, cab mounting bolts, boom foot pins, A-frame pins and pin keeper plate bolts.
Grades subsea & offshore runs on.
ASTM A320 Grade L7
The low-temperature twin of B7 — same 4140 Cr-Mo steel, same 125 ksi strength, but impact tested at −150 °F for cryogenic and cold-climate service.
ASTM A193 / ASME SA-193ASTM A193 Grade B7
The workhorse alloy-steel bolting grade for flanges, valves and pressure equipment — 125 ksi tensile, quenched and tempered 4140.
ASTM A1082 bolting · ASTM A276 / A479 bar · ASTM A182 F53Super Duplex 2507 Stainless (UNS S32750)
25 Cr super duplex with a PREN above 40 — 116 ksi tensile and 80 ksi yield for the most aggressive seawater, sour and chloride bolting.
ASTM A1082 bolting · ASTM A276 / A479 bar · ASTM A182 F51 / F60Duplex 2205 Stainless (UNS S31803 / S32205)
Twice the yield strength of 316 with far better chloride stress-corrosion resistance — the standard duplex for offshore, seawater and sour-service bolting.
ASTM B637 bar · AMS 5662 / 5663 · API 6A CRAInconel 718 (UNS N07718)
The premier high-strength nickel superalloy — 185 ksi tensile and 150 ksi yield from cryogenic temperatures to 1200 °F, with corrosion and sour-gas resistance to match.
ASTM B446 bar · ASTM F468 / F467 fastenersInconel 625 (UNS N06625)
The corrosion all-rounder — 120 ksi in the annealed condition, resistant to seawater, sour gas, acids and oxidation to 1800 °F, and the F468 nickel fastener grade Ni 625.
ASTM F468 / F467 fasteners · ASTM B865 barMonel K-500 (UNS N05500)
Monel 400 corrosion resistance with more than twice the strength — 130 ksi tensile, 90 ksi yield and 24 to 37 HRC — for pump shafts, subsea fasteners and oil-tool components.
Jobs we’ve made in these grades.
