Home » DIN 137B Spring Washer (Crinkled) – A4 Stainless

DIN 137B Spring Washer (Crinkled) – A4 Stainless

DIN 137B Crinkled Spring Washer — A4 Marine Stainless Steel (SUS316), Whitened & Passivated

FULLERKREG DIN 137B crinkled spring washers are manufactured to DIN 137 Type B standard in A4 marine stainless steel (SUS316 / 1.4401 / 06Cr17Ni12Mo2) with a whitened and passivated surface finish. DIN 137 Type B is a crinkled (wavy) spring washer featuring multiple corrugations around the ring circumference, providing distributed multi-point axial spring force with a larger outer diameter than DIN 128B. A4 stainless steel contains 2–3% molybdenum, providing superior resistance to chloride corrosion, seawater, and acidic environments — the correct choice for marine, offshore, and coastal applications where A2 (SUS304) may suffer pitting corrosion.

Product Highlights

  • Standard: DIN 137 Type B (Crinkled / Wavy Spring Washer)
  • Material: A4 Marine Stainless Steel (SUS316 / 1.4401 / 06Cr17Ni12Mo2)
  • Surface Treatment: Whitened & Passivated
  • Size Range: M3 – M36
  • Profile: Type B — Crinkled / Wavy (multiple corrugations, larger OD than DIN 128B)
  • Molybdenum content: 2–3% — superior chloride & seawater resistance vs. A2
  • Function: Multi-wave axial spring force — anti-loosening, load distribution, no surface marking
  • Non-magnetic, non-sparking
  • RoHS & REACH Compliant

Dimensional Specifications — DIN 137 Type B (Crinkled), A4 Stainless

All dimensions in millimeters (mm). Per DIN 137 Type B.

Nominal Size For Bolt d1 min d2 max h min h max s (thickness)
3 M3 3.2 7.5 0.8 1.2 0.5
4 M4 4.3 9.5 1.0 1.4 0.6
5 M5 5.3 11.5 1.2 1.7 0.8
6 M6 6.4 14.0 1.5 2.1 1.0
8 M8 8.4 18.0 2.0 2.8 1.2
10 M10 10.5 22.0 2.5 3.5 1.5
12 M12 13.0 26.0 3.0 4.2 1.8
14 M14 15.0 30.0 3.5 4.9 2.0
16 M16 17.0 34.0 4.0 5.6 2.5
20 M20 21.0 42.0 5.0 7.0 3.0
24 M24 25.0 50.0 6.0 8.4 3.5
30 M30 31.0 62.0 7.5 10.5 4.0
36 M36 37.0 74.0 9.0 12.6 5.0

All dimensions in mm per DIN 137 Type B. s = material thickness; h = free height (crinkled profile height). Same outer dimensions as DIN 137A — profile differs (wavy vs. curved).

DIN 137B vs. DIN 137A — Key Differences

Feature DIN 137 Type B (Crinkled) DIN 137 Type A (Curved)
Profile Crinkled / wavy (multiple corrugations) Single curved arc (dished)
Contact points Multi-point contact Continuous curved contact
Spring action Distributed multi-wave spring force Axial spring via single curve
Outer dimensions Same as DIN 137A Same as DIN 137B
Typical use General assemblies, multi-point load distribution Higher load, larger bearing area

A4 vs. A2 Stainless Steel — Key Differences

Property A4 (SUS316) — This Product A2 (SUS304)
Molybdenum (Mo) 2.0 – 3.0% None
Chloride resistance Superior — marine grade Good — general use
Seawater resistance Excellent Limited
Acid resistance Better (Mo addition) Standard
Typical use Marine, offshore, coastal, chemical General outdoor, food, fresh water

Material & Mechanical Properties — A4 Marine Stainless Steel (SUS316)

Property Value
Material Grade A4 / SUS316 / 1.4401 / 06Cr17Ni12Mo2
Cr Content 16.0 – 18.0%
Ni Content 10.0 – 14.0%
Mo Content 2.0 – 3.0%
Surface Treatment Whitened & Passivated
Magnetic Non-magnetic (austenitic)
Operating Temperature -196°C to +300°C
Corrosion Resistance Excellent — seawater, chlorides, acids, marine environments
RoHS / REACH Compliant

Application Scenarios

  • Marine & offshore structures — seawater splash zones, boat fittings, dock hardware
  • Coastal construction — salt air environments, bridges, coastal infrastructure
  • Chemical processing equipment — resistance to acids and chloride-containing media
  • Food & beverage processing — hygienic, easy to clean, non-toxic
  • Swimming pools & water treatment — chlorinated water resistance
  • Soft material assemblies — crinkled profile distributes load without sharp edge marking
  • Thermal cycling applications — multi-wave spring action compensates for expansion/contraction

Product Photo Gallery

FULLERKREG DIN 137B Crinkled Spring Washer, A4 Marine Stainless Steel:

[ Photo 1 ] [ Photo 2 ] [ Photo 3 ] [ Photo 4 ]

Why Choose FULLERKREG?

  • 🏭 Direct manufacturer — factory in China, no middlemen
  • 📐 Strict DIN dimensional control — 100% inspection on critical dimensions
  • 🌍 Global export experience — serving distributors in Europe, North America, Southeast Asia
  • 📦 Flexible MOQ — small trial orders and large bulk shipments both welcome
  • 📋 Full documentation — material certs, RoHS declarations, test reports available
  • ⚡ Fast lead times — standard sizes in stock, ready to ship

Frequently Asked Questions

Q: What is DIN 137 Type B?
A: DIN 137 Type B is a crinkled (wavy) spring washer with multiple corrugations around the ring circumference. It generates distributed multi-point axial spring force with a larger outer diameter than DIN 128B, providing higher load capacity and better load distribution. No sharp edges — no surface marking.

Q: What is the difference between DIN 137B and DIN 137A?
A: DIN 137A is curved (single dished arc); DIN 137B is crinkled/wavy (multiple corrugations). Both share the same outer dimensions. Type B provides multi-point contact; Type A provides continuous curved contact.

Q: Why choose A4 over A2 for marine applications?
A: A4 (SUS316) contains 2–3% molybdenum which significantly improves resistance to chloride pitting and crevice corrosion. In seawater, coastal, or chloride-rich environments, A4 is the correct choice where A2 (SUS304) may suffer pitting.

Q: Do you provide material test certificates?
A: Yes. Mill certificates, chemical composition reports, and dimensional inspection reports are available upon request.

FULLERKREG Fasteners — Precision DIN Standard Fasteners, Direct from Manufacturer.
For wholesale inquiries, technical questions, or custom orders, please contact our sales team.

Sorry, this collection is empty.
Continue shopping