Our ASTM 310s Hex Bolts deliver unmatched heat resistance where ordinary fasteners warp or corrode.
The cold-forged heads provide 600 MPa tensile strength,crucial for boiler tie rods or pyrolysis reactors. You'll get 3x the service life of 304 bolts in oxidizing environments. Every batch comes with EN 10204 3.1 certs validating chemistry and strength.
We offer two finishes: Bright annealed for a smooth, clean look and pickled (ASTM A380) to remove any heat scale from manufacturing.
Our threading is done with precision: UNC threads ,ensuring a tight fit with nuts. We also provide custom lengths tolerance, using cold heading machines that avoid weakening the metal. Every bolt gets a 100% magnetic particle test (ASTM E709) to check for surface cracks before shipping.
As a Chinese manufacturer supplying European and American industrial furnace makers. Our raw material undergoes vacuum arc remelting (VAR) , tested via our in-house OES machine.
We keep 180-300 tons in stock warehouse, covering sizes from ½" to 2½" and lengths 2" to 16". Inventory updates daily on our website, a leave within 6 days-handy for meeting your customers' tight project timelines.
Orders over 30 tons get a 6% discount, plus free pickling and 18% of sea freight.
Here's our guarantee: If any ASTM 310s Hex Bolt fails to meet ASTM A193 mechanical standards at high temperatures we'll replace it within 7 days and refund all shipping costs. We also lock prices for 40 days on confirmed orders, with a 2% bonus discount if you reorder within 60 days.
310S Stainless Steel (AISI 310S; DIN 1.4845)
Chemical Composition
Cr: 24.0-26.0%, Ni: 19.0-22.0%, C: ≤0.08%, Mn: ≤2.0%, Si: ≤1.5%, P: ≤0.045%, S: ≤0.030%
Mechanical Properties
Tensile Strength: ≥600 MPa
Yield Strength: ≥205 MPa
Hardness: ≤217 HB (Brinell)
Elongation: ≥40%
Temperature Resistance
Continuous service: up to 1150°C (oxidizing environments); short-term: up to 1200°C
Corrosion Resistance
Excellent oxidation resistance at high temperatures; resistant to sulfurous gases, nitric acid, and moderate chloride environments
Magnetic Property
Non-magnetic (annealed condition)
Metric Size (M)
Thread Pitch (mm)
Hex Head Width (mm)
Hex Head Height (mm)
Length Range (mm)
Imperial Equivalent
Thread Type (Imperial)
UNC (5/16"-18), UNF (5/16"-24)
UNC (3/8"-16), UNF (3/8"-24)
UNC (1/2"-13), UNF (1/2"-20)
UNC (5/8"-11), UNF (5/8"-18)
UNC (3/4"-10), UNF (3/4"-16)
Standard Compliance
Key Applications
ISO 4017, DIN 933, ASTM A193
High-temperature industrial furnaces and kilns
Petrochemical reactors and heat exchangers
Power plant boilers and exhaust systems
Aerospace and automotive high-heat components
Incinerators and sulfur processing equipment
Frequently Asked Questions
Q: Can you share some of your customer references or case studies?
A: Sure, we can share case studies of customers in your industry (e.g., oil & gas, construction) while protecting their privacy.
Q: What is your policy for product returns or replacements?
A: If products have quality issues caused by us, we'll arrange replacements or refunds within 30 days of receipt.
Q: Can you provide a certificate of origin (CO) for customs clearance?
A: Yes, we can provide CO, as well as other documents like commercial invoices and packing lists required for customs.
