Drawing-Based / Per Sample / Non-standard Special Head Bolts, Step Bolts, Long Shank Bolts

Specializing in complex fastener challenges. With 15 years of cold forging and CNC expertise, we transform your engineering drawings into high-precision reality. Whether it's unique head shapes, special threads, or exotic materials, EternalFast delivers reliability.

• Extreme Scale & Heavy-Duty: Specializing in large-diameter Heavy-Duty Bolts (up to 3 1/2” / M90+) and Extra-Long Studs (up to 1000mm+) for infrastructure and heavy machinery.
• OEM/ODM, Technical Consulting, Prototype to Mass Production
• Manufacturing Process: Integrated Multi-station Cold Forging for high-volume grain structure alignment, followed by CNC Secondary Machining for complex geometries (e.g., cross-drilled holes, eccentric heads).Shoulder & Shank Precision: Tolerance control up to g6/h7 for shoulder diameters to ensure perfect fit in rotational or sliding applications.
• Concentricity: Stringent control of head-to-shank and thread-to-shank concentricity within 0.05mm TIR (Total Indicator Reading).
• Under-head Fillet: Optimized radius design to reduce stress concentration, enhancing fatigue resistance under high-vibration environments.
• Thread Run-out: Precision-ground thread rolling dies to ensure minimal run-out and smooth engagement for automated assembly.

For high-value custom fasteners, we provide premium protection to ensure zero-defect delivery:
Precision Protection

• We use Individual Plastic Netting or Bubble Bags for step bolts to prevent any scratches or collision damage to critical diameters.

Inner Packing

• Available in small reinforced white boxes or polybags with customized private labeling and barcode support.

Master Cartons

• Double-wall corrugated export cartons (Max weight: 25kg/55lbs per box) to withstand long-distance sea freight.

Palletization

• ISPM 15 compliant fumigation-free wooden pallets or plastic pallets, secured with heavy-duty stretch wrap and PET strapping.

Prototypes/Urgent Orders

• Express delivery via DHL, FedEx, or UPS for 3-5 day global arrival.

Our commitment to precision is backed by rigorous inspection protocols and international standards:
Dimensional Integrity

• A Full Inspection Report is provided with every shipment, ensuring 100% compliance with your technical drawings (±0.01mm tolerance verification).

Material Traceability

Each batch includes an EN 10204 3.1 Material Test Report (MTR) , detailing the chemical composition and mechanical properties.

Advanced Inspection

For automated assembly lines, we offer 100% Optical Sorting to eliminate any dimensional outliers or surface defects.

Certified Excellence ： ISO 9001:2015 certified manufacturing facility.

• RoHS & REACH compliant finishes.
• PPAP Level 3 documentation available for automotive industry partners.