Structural fasteners & ASTM bolting

Bolt and nut for non-preloaded structural connections. Separate washers where required by the project; regular sizes and project-specific production.

High-strength assemblies intended for preloading: HR, HV and HRC systems, with components and installation matched to the project.

From grade to assembly configuration: Heavy Hex bolts and Twist-Off assemblies, with dedicated A325 and A490 grades.

A325 is handled as a grade within ASTM F3125/F3125M, with nut, washer and finish requirements captured in the enquiry.

A490 bolting: coating, components and documentation are assessed against the applicable specification rather than inherited from A325.

Very-high-strength bolt, nut and washer assemblies, handled through a specification distinct from F3125.

Fixed-spline assemblies: identify the bolt, nut, washer arrangement and installation requirements together.

Nuts for structural and mechanical enquiries, including Grade DH where specified by the project.

Hardened washers for specified assemblies, with type, dimensions and finish maintained as separate parameters.

Bolts, studs and other externally threaded fasteners, through a route separate from F3125 structural bolts.

Bolts and studs for flanges, valves and pressure equipment: specify grade, class, dimensions and service conditions.

Nuts associated with bolting enquiries for high pressure and/or temperature service. Pairing depends on grade and service requirements.

Bolts and studs in L7 and L7M, separate from A193 and linked to applicable nut and testing requirements.

A325, A490, DIN 6914/6915/6916 and BS 4395: references for existing project specifications, without automatic equivalence claims.