Spring Washer

Spring Washer — Split Ring Lock Washer | DIN 127 / GB/T 93 | Anti-Loosening Solution

Spring washers (also known as split ring washers or helical spring lock washers) are elastic fastening components designed to prevent bolt and nut loosening under vibration and dynamic loads. Manufactured to DIN 127 and GB/T 93 standards, our spring washers feature a split ring design with an angled cut that creates spring tension when compressed. Available in sizes from M3 to M36 in carbon steel and stainless steel with multiple coating options, spring washers provide reliable locking performance in machinery, automotive, and industrial equipment applications.

Material & Specifications

Size Range	M3 to M36 / #4 to 1-1/2″
Standard	DIN 127 (Standard), DIN 128 (Curved), GB/T 93, GB/T 7244, JIS B 1251, ASME B18.21.1
Material	Carbon Steel (spring steel 65Mn, 60Si2Mn), 304 Stainless Steel (A2), 316 Stainless Steel (A4)
Surface / Coating	Hot-Dip Galvanized (HDG), Electroplated Zinc Blue/White, Color Zinc/Yellow, Dacromet, Multi-Element Alloy Co-Permeation, Black Oxide/Phosphate
Hardness	HRC 40-50 (carbon spring steel), HRC 30-45 (stainless steel)
Types	Standard Split Ring, Heavy Series (DIN 127 Type B), Light Series

Surface Treatment & Zinc Coating Quality

At BoltNutsPlus, we understand that surface treatment is critical to fastener longevity and performance. Our washers undergo rigorous coating processes to ensure maximum corrosion resistance and durability. We offer five premium coating options, each tested to international standards:

• Hot-Dip Galvanizing (HDG) — Thick zinc layer (50-120μm) providing superior long-term corrosion protection for outdoor, marine, and industrial environments. Compliant with ISO 1461 / ASTM A153 standards. Salt spray resistance: 500-1,000+ hours. HDG washers are ideal for structural steel assemblies exposed to harsh weather.
• Electroplated Zinc Blue-White (Zn Blue/White) — Bright, clean silver-blue appearance with 5-15μm zinc layer. Cr3+ passivation technology, fully RoHS compliant. Ideal for indoor machinery, electronics, and general-purpose applications requiring aesthetic appeal and moderate corrosion resistance.
• Color Zinc / Yellow Zinc (Iridescent Passivation) — Multi-colored iridescent passivation film offering enhanced corrosion resistance (100-200 hours salt spray) with a distinctive golden finish. Widely preferred in automotive, agricultural equipment, and construction machinery sectors for its balanced protection and visual appeal.
• Dacromet Coating — Advanced water-based zinc-chromium coating technology with NO hydrogen embrittlement risk. Provides 1,000+ hours salt spray resistance, making it the preferred choice for high-strength fasteners in extreme environments. Environmentally friendly (no heavy metal discharge), RoHS/ELV compliant, ideal for automotive and wind energy applications.
• Multi-Element Alloy Co-Permeation — Zinc-aluminum-rare earth alloy layer offering 2-3x the corrosion resistance of traditional galvanizing. Features self-healing properties at scratch points, ensuring long-term protection even in damaged areas. Ideal for critical infrastructure, power transmission towers, coastal projects, and marine installations.

Key Features

• Split ring design with angled cut creates consistent spring tension to resist loosening from vibration
• Elastic recovery maintains preload after thermal cycling and material relaxation in bolted joints
• Sharp edges on the split ends bite into both the nut and bearing surface for mechanical anti-rotation
• High-quality spring steel (65Mn/60Si2Mn) with optimal hardness balance between elasticity and toughness
• Available in heavy series for demanding applications and light series for general-purpose use
• Compatible with all standard hex bolts, hex nuts, and studs across metric and imperial systems

Applications

• Automotive engines, transmissions, chassis, and suspension assemblies — vibration-rich environments
• Industrial machinery, compressors, pumps, and vibrating equipment mounting
• Railway track fastenings and rolling stock assemblies requiring anti-loosening performance
• Agricultural equipment, harvesters, and tillage machinery exposed to constant vibration
• Construction equipment, excavators, and heavy-duty earth-moving machinery
• Electric motors, generators, and rotating equipment subject to cyclic loading

Why Choose BoltNutsPlus?

• ISO 9001:2015 Certified Manufacturing — consistent quality you can trust on every batch
• 15+ Years of Export Experience — serving 40+ countries across 6 continents
• Full Traceability — material certificates (EN 10204 3.1) and comprehensive test reports included
• Custom Packaging & OEM/ODM — your brand identity, your specifications, our precision manufacturing
• Third-Party SGS / Bureau Veritas Inspection Available upon request
• 24-Hour Quote Response — same-day reply for urgent requirements; standard 24-hour turnaround