RapidBolt
Pipeline & process flanges
ASME B16.5 and B16.47 flanged joints in hydrocarbon, steam and utility service.
Stud length follows flange class, facing and gasket thickness.
TECHNICAL REFERENCE / BY EQUIPMENT
EquipmentBolting Guide
The right grade for every joint — flanges, valves, turbines, pumps and exchangers.
Maintenance planners and buyers search by equipment, not by specification. This guide maps the bolting grades most often specified for each equipment type, so your RFQ starts in the right place.
EN 10204 3.1 / 3.21/4″–6″ / M5–M150KITTED & TAGGED
SELECT YOUR EQUIPMENT
Bolting by equipment type
Valves — bonnet, body & gland
Gate, globe, ball and check valve bonnet and body-joint studs, gland bolts and packing hardware.
Sour service bolting is typically hardness-limited per NACE MR0175 / ISO 15156.
Turbines, casings & HRSG
Turbine casing, steam chest, HRSG and high-temperature header bolting.
Grade selection is driven by the OEM specification for creep and relaxation.
Offshore, subsea & LNG
Topsides, subsea connectors, cryogenic and seawater-exposed bolted joints.
Coating friction changes torque — confirm nut factor with the coating data.
Mining — pumps, crushers & mills
Slurry pump casings, crusher and mill liners, screen decks and large-diameter structural joints.
Vibration-exposed joints often specify wedge-locking washers or tensioning.
Heat exchangers & pressure vessels
Channel covers, girth flanges, floating heads and nozzle flanges in cyclic thermal service.
Through-hardened washers support even load during controlled tightening.
QUICK SELECTION MATRIX
Service condition → stud and nut grade
| SERVICE | STUD / BOLT | NUT | |
|---|---|---|---|
| Ambient carbon/alloy service | A193 B7 | A194 2H | View |
| Low temperature (impact tested) | A320 L7 / L7M | A194 Grade 4 / 7 | View |
| Elevated temperature | A193 B16 | A194 Grade 4 / 7 | View |
| Sour service (hardness-limited) | A193 B7M / A320 L7M | A194 2HM / 7M | View |
| Austenitic stainless | A193 B8 / B8M | A194 Grade 8 / 8M | View |
| Seawater / chloride | Duplex / super duplex | Matched grade | View |
| High temp & corrosive | Inconel 625 / 718, C-276 | Matched grade | View |
General reference only, not a design specification. Your project piping specification, the equipment manufacturer’s data and the governing standards determine grade, size and tightening method.
SHUTDOWN COMING UP?
Send the bolting list. We’ll kit it by equipment tag.
Studs, heavy hex nuts, through-hardened washers and gaskets, kitted and tagged per flange or equipment item, with certification compiled before dispatch.
FAQ
Equipment bolting questions
What bolting grade is used on standard process flanges?+
ASTM A193 B7 stud bolts with A194 2H heavy hex nuts are the most common combination for carbon and alloy steel flanges in ambient-temperature hydrocarbon service. Low-temperature service often specifies A320 L7, and high-temperature service A193 B16. The project piping specification governs.
Which bolting is used for valve bonnets?+
Valve bonnet and body-joint studs commonly follow the valve's design temperature and service — B7 or B16 for many carbon steel valves, B7M or L7M where sour-service hardness limits apply, and nickel alloys in corrosive or high-temperature duty. Always follow the valve manufacturer's specification.
Can you supply complete bolting kits by equipment?+
Yes. We supply stud bolts, heavy hex nuts, through-hardened washers and gaskets kitted and tagged per flange or equipment item, from 1/4" to 6" and M5 to M150, with EN 10204 3.1 certification.
Is this guide a design specification?+
No. This guide is general reference for procurement and maintenance planning. Grade, size and tightening method must be confirmed against your project specification, the equipment manufacturer's data and the relevant standards.