RAYCHIN LIMITED

Hex Bolts – Partial Thread (DIN 931 / ISO 4014)

Alloy 330 hex bolts with partial thread manufactured to DIN 931, ISO 4014, and ASME B18.2.1 standards. Features a hex head with a partially threaded shank, providing unthreaded length for shear strength and alignment. Ideal for high-temperature applications up to 1150°C in furnace components, heat exchangers, and structural assemblies. Precision rolled threads for superior strength and high-temperature performance. Available in sizes from M6 to M48 (metric) and 1/4" to 2" (inch) in various lengths. Supplied in solution annealed condition per ASTM B511.

Hex Bolts – Full Thread (DIN 933 / ISO 4017)

Alloy 330 hex bolts with full thread manufactured to DIN 933, ISO 4017, and ASME B18.2.1 standards. Features a hex head with threads extending the entire shank length, providing maximum thread engagement. Ideal for applications where the full length of the bolt must be threaded or where grip length adjustment is required. Precision rolled UNC, UNF, and metric threads for superior fatigue resistance. Available in sizes from M6 to M48 (metric) and 1/4" to 2" (inch) in various lengths. Supplied in solution annealed condition per ASTM B511.

Heavy Hex Bolts (DIN 6914 / ASME B18.2.1)

Alloy 330 heavy hex bolts manufactured to DIN 6914, ASME B18.2.1 (heavy hex series), and ASTM A325/A490 dimensional standards. Features a larger head configuration providing increased bearing area for high-temperature flange connections and pressure vessel applications. Essential for high-temperature bolting assemblies in furnace components and heat exchangers. The heavier head distributes load more effectively and resists dilation at elevated temperatures. Available in sizes from M12 to M48 (metric) and 1/2" to 2" (inch). Supplied with matching Alloy 330 heavy hex nuts.

Flange Bolts (DIN 6921 / ISO 4162)

Alloy 330 flange bolts manufactured to DIN 6921, ISO 4162, and ASME B18.2.3.3M standards. Features an integrated flange under the head that provides a larger bearing surface, eliminating the need for separate washers. The flange distributes clamping load evenly and provides vibration resistance. Ideal for high-temperature applications up to 1150°C in gas turbine and industrial equipment. Available with serrated flange for anti-rotation. Precision rolled threads for superior fatigue life.

Alloy 330 Bolts – API & NACE Compliant

Alloy 330 bolts certified to NACE MR0175 / ISO 15156 for sour service applications in oil and gas industry. Suitable for wellhead equipment, valve assemblies, subsea connections, and refinery applications exposed to H₂S environments at elevated temperatures. Available in all configurations with 100% NDT available including PMI, UT, and MPI. Full traceability and material certifications per ASTM B511.

Custom & Specialty Alloy 330 Bolts

Need a special head style, unusual thread configuration, or custom length for your high-temperature application? RAYCHIN engineers work with you to produce custom Alloy 330 bolts to your drawing. Options include T-head bolts, eye bolts, U-bolts, anchor bolts, and bolts with drilled heads for safety wiring. Expert heat treatment (solution annealed at 1038-1121°C) ensures optimum high-temperature performance. Manufactured to NAS, AN, MS, ANSI, ASTM, ASME, SAE, API, NACE, ISO, DIN, KS standards.

Metallurgical competence

Engineers on staff with deep expertise in nickel-based superalloys. We ensure proper solution annealing (1038-1121°C) for optimal high-temperature strength across all Alloy 330 bolts. Every heat is verified by in-house PMI testing to confirm chemistry. With 34-37% nickel and silicon addition, our bolts provide exceptional resistance to carburization, oxidation, and thermal cycling up to 1150°C.

Global approvals & traceability

Our quality system is ISO 9001:2015 and AS9100D certified; we also comply with NAS, AN, MS, ANSI, ASTM, ASME, SAE, API, NACE, ISO, DIN and KS. Full material traceability from melt to final packaging (EN 10204 3.1/3.2). Third-party inspections (ABS, DNV, Lloyds) available. All Alloy 330 bolts meet applicable ASTM B511, ASME SB511, AMS 5716, and all relevant bolt standards.

Precision head forming & thread rolling

In-house CNC cold heading, hot forging, and precision thread rolling capabilities ensure consistent head dimensions and thread geometry. Precision rolled threads provide superior fatigue life and dimensional accuracy. Accurate hex heads for positive wrench engagement. 100% thread and dimensional inspection available. Controlled underhead fillet for improved fatigue resistance in thermal cycling applications.

Custom solutions

Need a special head style, unusual thread configuration, or custom length for your high-temperature application? Our engineering team works with you to produce custom Alloy 330 bolts to your drawing. We provide specialized surface treatments and processing per customer requirements.