DIN 9250 Stainless Steel Serrated Safety Washers | S/M Type | HV 350-550 Hardened
PRODUCT PARAMETERS
Description
| Key Feature | Technical Specification | Operational Benefit (Trust Driver) |
| Double-Sided Teeth | Symmetrical radial serrations on both surfaces. | Maximum friction coefficient against bolt and workpiece. |
| Conical Design | Engineered disc spring shape. | Maintains preload tension even during structural “settling.” |
| Surface Hardening | Proprietary process achieving HV 350 – 550. | Guaranteed to “bite” into Grade 8.8 and 10.9 fasteners. |
| Corrosion Protection | Passivated or electropolished stainless steel. | Zero rust performance in marine and offshore environments. |
Dimensions
Data Overview
| Size (Metric) | Inner Dia (d1) [mm] | Outer Dia (d2) [mm] | Thickness (T) [mm] | Max. Height (h) [mm] | Weight [kg/1000pcs] |
| M4 | 4.3 | 7.0 | 0.50 | 0.80 | 0.08 |
| M6 | 6.4 | 10.0 | 0.70 | 1.10 | 0.25 |
| M8 | 8.4 | 13.0 | 0.80 | 1.30 | 0.50 |
| M10 | 10.5 | 16.0 | 1.00 | 1.50 | 0.85 |
| M12 | 13.0 | 18.0 | 1.10 | 1.65 | 1.20 |
| M16 | 17.0 | 24.0 | 1.30 | 2.00 | 2.10 |
| M20 | 21.0 | 30.0 | 1.50 | 2.30 | 3.50 |
| M24 | 25.6 | 36.0 | 1.80 | 2.80 | 6.20 |
| M30 | 31.0 | 45.0 | 2.00 | 3.20 | 11.00 |
Product Features & Engineering Logic
| Material Grade | Relevant Standard | Corrosion Resistance | Best For |
| SUS304 (A2) | ISO 3506 / AISI 304 | Standard Industrial | Outdoor construction, food equipment. |
| SUS316 (A4) | ISO 3506 / AISI 316 | High (Chloride resistant) | Marine engineering, chemical processing. |
| 254SMO | UNS S31254 | Extreme (Acid/Pitting) | Offshore platforms, desalination plants. |
Applications & Quality Assurance
Applications: Wind Power Generators, Railway Fastening, Automotive Suspension, Heavy Duty Rigging.
Quality Documentation: We provide MTC (Material Test Certificate) 3.1, Hardness Test Reports, and Dimension Inspection Reports for every batch.
FAQs
Q1: Why is surface hardening required for stainless steel safety washers?
Most stainless steel fasteners are relatively soft. To ensure the serrations can effectively “bite” into the bolt head and create a mechanical lock, the washer must have a higher hardness. Our process ensures a range of HV 350-550, making it suitable for high-tensile bolts.
Q2: Can I use S-series and M-series interchangeably?
S-series (Standard) is designed for regular bolts. M-series (Medium) has a larger outer diameter to reduce surface pressure, making it ideal for elongated holes or softer clamping surfaces.
