STAINLESS STEEL RECTANGULAR SECTION SPRING WASHERS DIN 127

Rectangular Section Spring Washers DIN 127 — DIN 127 is the classic split lock washer - a single helical coil, cut through at one point, rectangular in cross-section. As the bolt or nut is tightened, the coil compresses flat and stores spring energy, while the sheared, slightly raised ends of the cut bite into the bearing faces on either side, giving the joint some resistance to back-rotation under vibration. It is a familiar, low-cost anti-loosening measure across general mechanical and engineering assembly, and it remains a reasonable choice for everyday fixings that see moderate vibration but are not safety-critical. Where it falls short is in higher-reliability or heavily dynamic applications: the spring force and edge bite it provides are real but modest, and for joints where loosening would be a safety issue, a more positive method - nylon insert nuts, tab washers, or a conical spring washer to DIN 6796 - is generally the better specification. DIN 127 comes in Form A and Form B variants and is closely related to the square-section DIN 7980, which delivers a higher spring rate for the same nominal size at the cost of a slightly bulkier profile; the choice between the two usually comes down to how much anti-loosening performance the joint actually needs. Material and grade matter more here than on a plain flat washer, because a spring washer's whole function depends on the material's spring temper: carbon spring steel gives the best fatigue and spring performance for demanding mechanical service, while A2 (304-equivalent) stainless trades a little spring performance for corrosion resistance in general outdoor or washdown environments, and A4 (316-equivalent) is worth the extra cost only where the assembly is genuinely exposed to chlorides or aggressive chemicals, since stainless spring washers are inherently a compromise against the very best carbon spring steel performance. Selecting correctly means matching the bore to the bolt diameter and choosing Form A or B per the drawing, then weighing whether this level of locking is sufficient or whether the joint calls for something more positive.

FAQs
Are DIN 127 spring washers a reliable anti-vibration solution?
They provide some resistance to loosening through spring tension and edge bite, but are not considered a high-reliability locking method for critical or heavily vibrating assemblies, where more positive methods are often preferred.

How does DIN 127 differ from DIN 7980?
DIN 127 has a rectangular cross-section, while DIN 7980 uses a square cross-section, giving greater material volume and a higher spring rate for the same nominal size.

Can a DIN 127 washer be reused after disassembly?
Repeated compression cycles gradually reduce a spring washer's stored energy through fatigue and set, so for a joint that is regularly stripped and rebuilt, fitting a fresh washer each time is the safer practice.