RAYCHIN LIMITED

All-Metal Lock Nuts (DIN 980 / ISO 7042)

Alloy 330 all-metal lock nuts manufactured to DIN 980, ISO 7042, and ASME B18.16.6 standards. Features an integral locking mechanism through controlled thread deformation or elliptical offset, providing prevailing torque without any non-metallic inserts. Ideal for high-temperature applications up to 1150°C where nylon inserts cannot be used. The all-metal design ensures consistent locking torque even after repeated use at elevated temperatures. Available in hex and heavy hex configurations. Sizes from M3 to M48 (metric) and #4 to 1-1/2" (inch). Supplied in solution annealed condition per ASTM B511.

Nylon Insert Lock Nuts (DIN 985 / ISO 7040)

Alloy 330 nylon insert lock nuts manufactured to DIN 985, DIN 982, ISO 7040, ISO 10511, and IFI 100/107 standards. Features a non-metallic locking element (nylon ring) that deforms elastically when engaged with the mating thread, providing consistent prevailing torque without damaging the bolt threads. Ideal for applications requiring repeated assembly and disassembly up to 120°C. The nylon insert also seals against leakage along the thread path. Available in hex and heavy hex configurations. Sizes from M3 to M36 (metric) and #4 to 1-1/4" (inch). Suitable for applications where high temperatures are intermittent or where maximum service temperature is below 120°C.

Heavy Hex Lock Nuts (DIN 6915 / ASME B18.2.2)

Alloy 330 heavy hex lock nuts manufactured to ASME B18.2.2, DIN 6915, and ASTM A563 specifications with locking features. Features a larger wrenching surface for increased bearing area, combined with all-metal or nylon insert locking elements. Essential for high-temperature flange connections, furnace closures, and heavy equipment subject to vibration. Available in both all-metal (to 1150°C) and nylon insert (to 120°C) versions. Sizes from M12 to M48 (metric) and 1/2" to 1-1/2" (inch). Supplied with matching Alloy 330 bolts and studs for complete locking fastener assemblies.

Jam Lock Nuts (DIN 439 / ISO 4035 with locking)

Alloy 330 jam lock nuts manufactured to DIN 439, ISO 4035, and ASME B18.2.2 standards with locking features. Reduced height nuts designed for limited clearance applications, available with all-metal or nylon insert locking elements. Ideal for valve assemblies, instrumentation, and control systems where space is constrained but vibration resistance is required. Available in hex and heavy hex configurations. Sizes from M3 to M36 (metric) and #4 to 1-1/4" (inch). Precision machined from solution annealed Alloy 330.

Alloy 330 Lock Nuts – API & NACE Compliant

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

Custom & Specialty Alloy 330 Lock Nuts

Need a special locking configuration, unusual thread size, or custom performance requirements for your high-temperature application? RAYCHIN engineers work with you to produce custom Alloy 330 lock nuts to your drawing. Options include slotted lock nuts, castle lock nuts, coupling lock nuts, and nuts with special locking elements. 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 and locking fastener technology. We ensure proper solution annealing (1038-1121°C) for optimal high-temperature strength across all Alloy 330 lock nuts. Every heat is verified by in-house PMI testing to confirm chemistry. With 34-37% nickel and silicon addition, our lock nuts provide exceptional resistance to carburization, oxidation, and thermal cycling up to 1150°C while maintaining reliable prevailing torque.

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 lock nuts meet applicable ASTM B511, ASME SB511, AMS 5716, and lock nut standards including DIN 980, DIN 985, IFI 100/107.

Precision forming & locking element integration

In-house CNC tapping, thread forming, and precision locking element integration ensure consistent thread geometry and reliable prevailing torque. All-metal lock nuts feature precisely controlled thread deformation; nylon insert lock nuts feature securely crimped locking elements. 100% torque testing available. 100% thread inspection available.

Custom solutions

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