DIN 127 Spring Washers

DIN127‑1987, superseded but still widely used in engineering practice.
Type A: standard type (flat‑faced); Type B: heavy‑duty type (square‑faced).
Approximate equivalent in Chinese standard: GB/T 93.
Material Requirements (per DIN 267‑26)

1. Carbon spring steel (most common)

• Grade: FSt (spring steel), complying with DIN 17221 / DIN 17222.

• Common domestic equivalents: 65Mn, C67, C70, 70# steel.

• Heat treatment: quenching and tempering.

2. Stainless steel

• Grades: A2 (AISI 304), A4 (AISI 316) for corrosion‑resistant applications.

• Heat treatment: work‑hardened (no quenching‑tempering for stainless spring washers).

Quality & Mechanical Requirements

1. Hardness

• Carbon steel: HRC 44‑50

• Stainless steel (A2/A4): HV 420‑500

2. Surface condition

• No cracks, burrs, sharp edges, scale or material defects.

• Surface finish: zinc‑plated, phosphate‑coated or passivated for stainless steel.

• No hydrogen embrittlement risk for plated carbon steel; suitable baking treatment required.

3. Spring performance

• The washer shall maintain elastic resilience under compression load.

• After being compressed to solid height, the washer shall not show permanent deformation or fracture.

4. Dimensional tolerance

• Dimensions, thickness, outer diameter, inner diameter and chamfer comply with DIN 127.

• Tolerances for dimensions are specified in the standard.

5. Marking & inspection

• Batch inspection covers hardness, visual check, dimension verification and compression test.

• The washer shall not have cracks or material inclusions.

Notes

• DIN127 has been withdrawn; modern replacement standard is ISO 10673.

• Type A: standard spring washer; Type B: heavy‑load spring washer.