Bolts Manufacturer & Custom Automotive Bolt Supplier
CNXD is a China-based bolts manufacturer and fasteners manufacturer supplying standard and custom bolts to automotive manufacturers, OEM suppliers, fastener distributors, and aftermarket buyers worldwide. From hex bolts to application-specific wheel, chassis, and engine fasteners, every batch is produced with documented traceability.
A Bolts Factory Built for OEM-Grade Consistency
Sourcing bolts overseas carries real risk: inconsistent tolerances, missing test reports, and suppliers who cannot explain a batch failure. CNXD was built to remove that risk. As a specialized bolts factory, every process — from cold heading to surface treatment — runs inside our own 33,000 m² facility, so nothing is outsourced and nothing is untraceable.
- 18+ automated production lines under one roof, from cold heading to final inspection
- In-house CAD/CAM engineering team for drawing-based, non-standard bolt development
- 50+ precision inspection devices with CMM accuracy to ±0.005 mm
- IATF 16949 certified, with full PPAP Level III and FMEA documentation on request
Bolt Types We Manufacture
As a full-range bolts manufacturer, CNXD produces standard fasteners to DIN, GB, JIS, ANSI, and BS specifications, alongside application-specific and fully custom bolts developed from your own drawings or samples.
Hex Bolts
DIN933 hex bolts for automotive, machinery, and general fastening applications.
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Flange Bolts
Flange bolts for automotive chassis, engines, machinery, and load-bearing connections.
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Allen Bolts
Allen bolts for compact spaces, precision assembly, and high-strength fastening.
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Stud Bolts
Standard and custom stud bolts for automotive and industrial fastening applications.
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Weld Bolts
Weld bolts designed for permanent fastening in automotive, sheet metal, and structural assemblies.
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T Boltss
T bolts for positioning, clamping, profile systems, machinery, and custom fastening applications.
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Shoulder Bolts
Precision shoulder bolts for guiding, pivoting, spacing, and mechanical positioning applications.
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Cylinder Head Bolts
High-strength cylinder head bolts for engine and powertrain assemblies.
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Lug Bolts
Automotive seat lug bolts for secure restraint-system mounting and vehicle safety assemblies.
View Product →Bolt Sizes, Threads & Standards
Standard bolt diameters range from Φ3–30 mm and lengths from 6–300 mm, while selected stud and flange bolt sizes extend up to M72 / 3/16″–4″. Both Metric and Inch systems are supported, including Metric coarse, UNC, Unified, left-hand and right-hand threads, and full- or half-thread designs.
| Attribute | Standard / Aftermarket Bolts | Custom OEM Bolts |
|---|---|---|
| Applicable Standards | DIN, GB, JIS, ANSI, BS catalog sizes | Customer 2D drawing, 3D file, sample, or OE/OEM part number |
| Tolerance Control | ±0.05 mm typical aftermarket tolerance | ±0.01 mm at tooling stage; CMM inspection to ±0.005 mm |
| Minimum Order Quantity | From 100 pcs (in-stock), 1,000 pcs (non-stock standard) | Typically from 1,000 pcs; flexible MOQ for long-term partners |
| Sample / Development Time | Ships from stock or short lead time | 25–30 days including tooling; rapid prototyping in 7–10 days |
| Documentation | Material certificate, dimensional report | Full PPAP Level III, FMEA, salt spray and tensile reports |
Materials, Strength Grades & Testing
As a stainless steel fasteners manufacturer and alloy steel specialist, CNXD selects material and grade based on load, temperature, and environment — not a one-size catalog default.
| Material Family | Typical Grades | Tensile / Hardness | Best Suited For |
|---|---|---|---|
| Carbon & Alloy Steel | 4.8, 8.8, 10.9, 12.9; 40Cr, 35CrMo | Up to 800+ MPa; 20–60 HRC | Chassis, suspension, general automotive |
| Stainless Steel | 304, 316, A2-70, Duplex | Corrosion-focused, moderate strength | Outdoor, humid, and mildly corrosive environments |
| Titanium & Nickel Alloys | Custom-developed high-performance alloys | Rated to 600°C service temperature | EV, oil & gas, wind energy applications |
Every batch is verified through CMM dimensional inspection, thread go/no-go gauging, dual Rockwell and Vickers hardness testing, tensile testing to 800+ MPa, torque verification up to 2000 Nm, metallographic grain analysis, and salt spray testing rated at 500+ hours.
Corrosion Protection & Surface Finishes
Available finishes include zinc plating (blue, colored, or white passivation), black oxide, phosphating, hot-dip galvanizing, Dacromet, zinc diffusion, zinc-nickel alloy, chrome plating, nickel plating, anodizing, and custom coatings. Surface treatment can raise surface hardness by 20–40% and extend service life by 30% or more, with select combinations achieving 500+ hours of salt spray resistance.
For chemical processing, outdoor, or marine-adjacent environments, we typically recommend 304/316 stainless, duplex stainless, titanium, or nickel alloys paired with Dacromet or zinc-nickel coating for long-term corrosion resistance.
Where Our Bolts Are Used
CNXD supplies automotive, energy, heavy machinery, and construction customers across wheel, chassis, engine, and general industrial applications.
Wheel & Hub Systems
Wheel and hub bolts for passenger cars, commercial vehicles, and trucks.
Chassis & Suspension
Camber bolts, flange bolts, and high-strength fasteners for chassis and suspension systems.
Engine & Powertrain
Cylinder head and connecting rod bolts for engine and powertrain assemblies.
Machinery & Industrial Equipment
Hex bolts, socket head bolts, studs, and custom bolts for heavy equipment and energy applications.
From Drawing to Mass Production
As a custom fasteners manufacturer, CNXD develops non-standard bolts from a 2D drawing, 3D file, physical sample, or OE/OEM part number. Our engineering team supports feasibility review, CAD design, and tooling development before any commitment to mass production.
Drawing & Feasibility Review
Submit technical drawings, OE/OEM part numbers, or a reference sample along with material, grade, and finish requirements.
Rapid Prototyping
Fast-turn prototypes confirm fit and function before full tooling investment.
Tooling & Sample Production
Full mold development and initial production of approval samples for sign-off.
Mass Production
Batch production with 100% inspection or statistical sampling, plus full traceability documentation.
Customizable specifications include head style (hex, flange, socket, T-head, round, pan), diameter, length, shoulder length, thread length and pitch, material, strength grade, surface treatment, thread direction, and packaging. CNXD develops 200+ custom molds annually across automotive and industrial programs.
IATF 16949 Quality System & Full Traceability
Every batch is backed by material certificates, heat/lot numbers, dimensional reports, salt spray and tensile reports, hardness reports, and PPAP Level III documentation where required. CNXD is IATF 16949 certified and supports complete OEM documentation requirements.
Frequently Asked Questions
What information should I provide for a custom bolt quotation?
Please provide a technical drawing or specification, OE/OEM part number if available, a sample or reference part, vehicle or application details, and your required material, strength grade, and surface treatment.
Can CNXD develop a bolt from only a physical sample or OE number?
Yes. As a custom fasteners manufacturer, CNXD can develop bolts from physical samples, OE/OEM numbers, 2D drawings, 3D files, or application requirements alone.
Are custom logos and packaging available?
Yes. CNXD supports logo customization along with customized or co-branded packaging for OEM and distributor orders.
How is an OEM bolt batch traced if a quality issue occurs?
Each batch can be traced through production records, inspection data, PPAP documentation, and heat/lot information, giving you full visibility from raw material to shipment.
Does CNXD support both metric and inch bolt specifications?
Yes. CNXD supports both Metric and Inch systems, including UNC and other supported thread configurations, across diameters from Φ3–30 mm and lengths from 6–300 mm.
What is the minimum order quantity for standard and custom bolts?
In-stock aftermarket bolts start from 100 pieces. Non-stock standard bolts and most custom bolts typically start from around 1,000 pieces, with flexible MOQ available for long-term partners.
Ready to Source Bolts From a Certified Manufacturer?
Whether you need standard stock bolts, application-specific hardware, or a fully custom OEM program, our engineering team responds with a feasibility review and quotation.
Email: sales@cnxdauto.com | WhatsApp: +86 158 0587 8672 | Website: www.cnxdauto.com
Looking for a Reliable Bolts Manufacturer?
CNXD specializes in standard and custom automotive bolts, including hex bolts, flange bolts, cylinder head bolts, stud bolts, and other precision fasteners for OEM and industrial applications.
Our 33,000㎡ automated factory, 50+ testing devices, and IATF 16949 quality system guarantee durability, accuracy, and fast turnaround.
Share your project details — we’ll prepare a tailored quote and technical advice.
