Product Summary

Longze High-Precision Stainless Steel Hex Nuts are essential corrosion-resistant fasteners designed for demanding environments. Manufactured in Yongnian, China, our nuts

are cold-forged from premium austenitic stainless steel (SS304 and SS316), offering excellent resistance to oxidation, chemicals, and saltwater. Whether for a coastal solar farm, a

food processing plant, or a pharmaceutical laboratory, Longze stainless hexagon nuts provide the sanitary finish and structural longevity required for high-end industrial applications.

• ✔ Marine-Grade Corrosion Resistance: Our SS316 (A4) nuts contain molybdenum, providing superior protection against pitting and crevice corrosion in chloride-rich and maritime environments.

•  

• ✔ Precision 6H / 2B Threading: Every nut is tapped with high-precision CNC equipment to ensure a smooth, consistent fit on both metric and imperial bolts, reducing the risk of thread galling during manual or automated assembly.

•  

• ✔ Non-Magnetic Properties: Ideal for electronics and medical equipment, our fully annealed stainless nuts maintain low magnetic permeability, ensuring no interference with sensitive sensors or imaging devices.

•  

• Standards: DIN 934 (Metric), ASME B18.2.2 (Imperial), ISO 4032.

•  

• Thread Range: M2 to M64 | #2 - 2-1/2" (UNC/UNF).

•  

• Material Grade: SS304 (A2-70), SS316 (A4-80), SS316L (Low Carbon), 904L.

•  

• Strength Class: 50, 70, 80 (700 - 800 MPa Tensile Strength).

•  

• Surface Finish: Passivated (Clean/Bright), Electropolished, Plain.

Mechanical Properties & Material Standards

• Matching the stainless grade to the environmental requirements of the project.

• Grad	Material	Tensile Strength	Yield Strength	Hardness Range	Best Application
  A2-70 (SS304)	Edelstahl	700 MPa	450 MPa	200 - 280 HV	General Outdoor / Food
  A4-80 (SS316)	Edelstahl	800 MPa	600 MPa	240 - 320 HV	Marine / Coastal
  A4-70 (SS316)	Edelstahl	700 MPa	450 MPa	200 - 280 HV	Chemical Plants
  SS316L	Low Carbon	600 MPa	400 MPa	180 - 250 HV	High-Temp / Welding

Standard Cross Arm Dimensions

• Common dimensions for metric (DIN 934) and imperial (ASME B18.2.2) stainless hex nuts.

• Size (D)	Width Across Flats (s)	Height (m)	Pitch (Metric)	Max Torque (A2-70)
  M6 / 1/4"	10 mm / 7/16"	5.0 mm	1.0 mm	8.5 Nm
  M8 / 5/16"	13 mm / 1/2"	6.5 mm	1.25 mm	21 Nm
  M10 / 3/8"	17 mm / 9/16"	8.0 mm	1.5 mm	41 Nm
  M12 / 1/2"	19 mm / 3/4"	10.0 mm	1.75 mm	71 Nm

Passivation & Surface Integrity

• Ensuring 50+ years of maintenance-free service in corrosive environments.

• Treatment	Process	Salt Spray Test	Appearance	Best Environment
  Passivation	Nitric Acid	144 - 240 Hours	Bright / Clean	General Outdoor
  Electropolishing	Electrolytic	500 - 800 Hours	Mirror-like	Medical / Marine
  PTFE Coating	Fluoropolymer	1000 - 2000 Hours	Blue / Green	Oil & Gas / Subsea
  Pickling	Acid Wash	72 - 120 Hours	Dull / Clean	Industrial

Avoid Pitfalls:

• The "Seizing" Nightmare: Stainless steel threads have a natural oxide layer that can cause "cold welding" (galling). Longze recommends using anti-seize lubricants or choosing our Wax-Coated nuts for high-speed assembly.

•  

• Magnetic "Fake" Myth: Many customers think if a magnet sticks, it's not 304. Actually, cold-working can induce slight magnetism in 304. Longze provides Spectrometer Chemical Analysis for every batch to prove 100% material authenticity.

•  

• Intergranular Corrosion: For components that will be welded, we recommend SS316L (Low Carbon) to prevent carbon precipitation at the grain boundaries, which avoids structural weakness in the heat-affected zone.

•  

Perfect Fit Assembly:

• Matching Bolts: Always pair SS304 nuts with SS304 bolts. Mixing carbon steel and stainless steel leads to Galvanic Corrosion, which will cause the joint to fail prematurely.

•  

• Washer Integration: Use our Longze DIN 125 Stainless Flat Washers to distribute the load and prevent the nut from galling the surface of the base material.

•  

Quality Control & Logistics:

•  

• ISO 9001 Certified: 5-step QC including PMI (Positive Material Identification) via spectrometer, thread Go/No-Go gauging, and hardness testing.

•  

• Sea-Worthy Packaging: Nuts are packed in plastic-lined 25kg cartons, then secured in reinforced crates to ensure no contamination or flash rust during maritime export from our Yongnian hub.

• Q: What is the difference between SS304 and SS316? A: SS316 contains 2-3% Molybdenum, making it significantly more resistant to salt and acids. If your project is within 10km of the ocean, always use SS316.

• Q: Can you provide A4-80 (High Strength) stainless nuts? A: Yes. While standard stainless is A2-70/A4-70, we utilize specialized cold-working techniques to supply A4-80 grade with 800MPa tensile strength for structural applications.