Stainless Steel CNC Turning Fasteners – 304 / 316 (1.4301 / 1.4404)
Product Highlights
‑ Custom CNC‑turned stainless‑steel fasteners manufactured from grade 304 (1.4301) and 316 (1.4404) austenitic stainless steel, complying with ASTM F593 fastener specifications, covering standard and non‑standard bolts, studs, screws, pins, custom threaded components. ‑ 304 delivers excellent general‑purpose atmospheric and fresh‑water corrosion‑resistance; molybdenum‑alloyed 316 provides superior pitting & chloride‑stress‑corrosion‑cracking resistance for coastal, marine and moderate‑chemical service environments. ‑ Precise multi‑axis CNC turning process, strict thread tolerance control, good surface quality; avoids burrs and sharp edges for reliable assembly performance. ‑ Good ductility and toughness over wide temperature range; suitable for static and moderate‑vibration fastening applications; good weldability for on‑site assembly operations. ‑ Fully custom‑manufactured strictly according to customer CAD drawings; support special head shapes, custom thread pitches, undercuts, shoulder bolts and irregular fastener geometries. ‑ In‑house batch inspection capability; third‑party witness inspection (SGS, TUV, BV) is acceptable. ‑ Long‑term service life for food‑pharmaceutical machinery, marine equipment, general industrial machinery, architectural hardware and chemical‑plant corrosion‑resistant fastening assemblies.
Product Overview
This series of stainless‑steel CNC turning fasteners are custom‑machined threaded fastening components. Raw material adopts premium solid 304 / 316 stainless steel bar stock. Workpieces are processed by multi‑axis CNC turning, thread forming, deburring, passivation and surface anti‑rust treatment.
Grade 304 (1.4301) is cost‑effective for inland, atmospheric and fresh‑water environments. Grade 316 (1.4404) adds molybdenum element to improve resistance to salt‑spray, brine and weak‑chemical media. Product portfolio includes hex‑head bolts, socket cap screws, threaded studs, locating pins, shoulder bolts and various non‑standard special fasteners. Widely applied for equipment assembly requiring anti‑rust and corrosion‑resistant fastening performance.
Material Grade Characteristics – 304 / 316 (1.4301 / 1.4404)
‑ 304 (UNS S30400, EN 1.4301):Classic 18‑8 austenitic stainless steel. Good resistance to atmosphere, fresh water and weak organic media; good formability, machinability and weldability for general‑purpose fastening components. ‑ 316 (UNS S31600, EN 1.4404):Molybdenum‑bearing austenitic stainless steel. Markedly improved pitting and crevice corrosion resistance versus 304, suitable for chloride‑containing, coastal and mild‑chemical working conditions. ‑ Both grades retain good toughness from cryogenic up to continuous service temperature around 450 °C. ‑ Can achieve higher strength via cold‑working for higher‑class fastener requirements. ‑ Passivation treatment further enhances surface anti‑corrosion performance for finished fastener parts. ‑ Designed for fastening assemblies demanding corrosion resistance and reliable mechanical fastening performance.
Chemical Composition (Weight %)
表格
| Grade | EN Standard No. | C ≤ | Si ≤ | Mn ≤ | P ≤ | S ≤ | Cr | Ni | Mo | Fe |
|---|---|---|---|---|---|---|---|---|---|---|
| 304 | 1.4301 | 0.08 | 1.00 | 2.00 | 0.045 | 0.030 | 18.0‑20.0 | 8.0‑10.5 | — | Balance |
| 316 | 1.4404 | 0.08 | 1.00 | 2.00 | 0.045 | 0.030 | 16.0‑18.5 | 10.0‑14.0 | 2.0‑3.0 | Balance |
Mechanical Properties (Annealed Bar Base Material)
表格
| Property | 304 (1.4301) | 316 (1.4404) |
|---|---|---|
| Delivery Condition | Annealed / Cold Worked, Stress‑Relieved, Deburred | Annealed / Cold Worked, Stress‑Relieved, Deburred |
| Minimum Tensile Strength | ≥515 MPa | ≥515 MPa |
| Minimum 0.2% Yield Strength | ≥205 MPa | ≥205 MPa |
| Minimum Elongation (50mm gauge) | ≥40 % | ≥40 % |
| Maximum Brinell Hardness | ≤201 HB | ≤217 HB |
Related Material Grades
- Austenitic Stainless Steel Fastener Grades: 304L, 316L, 321
- Duplex Stainless Steel: 2205, 2507
- Nickel‑Base Alloy: Inconel 625, Hastelloy C276
- Monel Series: Monel 400, Monel K500
- Carbon & Alloy Steel Fastener Material: 4140, 4340
Key Advantages
- Corrosion‑Resistant Grade Selection 304 for general‑purpose inland & atmospheric service; 316 for salt‑spray, coastal and chloride‑rich environments; flexible grade choice balances performance and project cost.
- High‑Precision CNC Turning & Thread Quality Multi‑axis CNC turning ensures tight dimensional and thread tolerance; clean deburred surfaces for smooth assembly and consistent pre‑load performance.
- Wide Custom‑Fastener Capacity Produce standard and non‑standard special fasteners: shoulder bolts, custom‑pitch threads, special‑head shapes and custom‑length studs strictly from customer CAD data.
- Broad Temperature‑Range Mechanical Stability Maintain good toughness at low‑temperature and moderate‑temperature operating conditions; suitable for equipment exposed to large ambient‑temperature fluctuation.
- Complete Fastener‑Grade Quality Control Thread‑gauge inspection, dimensional check, PMI material verification; passivation surface treatment, can support salt‑spray test validation upon request.
Typical Applications
- Food & pharmaceutical processing equipment corrosion‑resistant bolt, stud and pin assemblies
- Marine and coastal‑region machinery, offshore auxiliary‑equipment fastening components
- General industrial machinery, automation‑equipment stainless‑steel threaded fasteners
- Architectural hardware, outdoor equipment and public‑facility anti‑rust fastening parts
- Chemical light‑industry equipment under mild‑chloride and weak‑corrosion working‑conditions
- Desalination and water‑treatment plant mechanical connection fastener parts
Processing Service
We provide integrated bar cutting, CNC turning, threading and full‑finish fastener‑manufacturing services, produce finished fastener parts strictly according to customer CAD/PDF drawings: ‑ Stainless‑steel bar blanking and cutting, stress‑relief treatment ‑ Multi‑axis CNC turning for head profiles, shanks, shoulders and custom features ‑ Thread turning / rolling, deburring and sharp‑edge removal ‑ Passivation, electropolishing and anti‑rust surface‑treatment ‑ Thread‑gauge checking, full‑dimension sorting and batch marking
We supply custom CNC‑turned stainless‑steel fasteners for machinery, food‑pharmaceutical, marine and chemical‑industry clients worldwide.
Quality Assurance
- PMI spectrometer full‑spectrum chemical‑composition analysis per raw‑material batch
- Thread‑gauge verification for thread accuracy; CMM / micrometer dimensional‑tolerance inspection
- Hardness test for material and strength‑class validation
- Visual inspection for burr, crack and surface‑defect detection
- Salt‑spray corrosion‑resistance test available on customer request
Mill Test Certificate EN 10204 3.1 can be provided together with shipment documents before delivery. Third‑party inspection witness is available upon request.
Packing & Delivery
Packing ‑ Inner packaging: Separated by anti‑rust paper, packed into waterproof polybag to avoid scratch and oxidation ‑ Outer packaging: Reinforced export cardboard box or fumigated wooden case for long‑distance sea and land transportation ‑ Custom special packaging available on customer request for bulk fastener‑order shipments
Lead Time Normally 15‑30 working days after receipt of advance payment. Exact delivery time depends on fastener complexity, order quantity, thread‑tolerance requirements and third‑party inspection schedule.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.