Spring lock washer

1. Raw Material Preparation & Coil Feeding

The process begins with a large coil of wire with a diameter corresponding to the cross-sectional thickness (W dimension in the standard) of the final washer. This coil is mounted on a pay-off reel and fed through a straightening machine to ensure a smooth, kink-free flow into the stamping press.

2. Stamping and Forming (Cold Heading)

This is the primary shaping operation, typically performed on a high-speed progressive die housed in a mechanical punch press.

● Step 1: Blanking: The straightened wire is fed into the progressive die. The first station punches out a flat, ring-shaped blank with a specific inner and outer diameter (ID and OD as per standard tables).

● Step 2: Curving and Slitting: The blank is transferred to the next station. Here, a forming punch forces the blank into a die, curving it into its characteristic single-coil helical shape. Simultaneously, the ends are sheared to create the precise gap (E dimension). This gap is critical for the washer's spring action, allowing it to compress and exert force.

● Step 3: Ejection: The fully formed, but soft, "green" washer is ejected from the die.

Finish: Hot dip galvanize per ASTM A153 or mechanical galvanize per ASTM B695, Class 50, type 11 clear coat.

Washers to meet ANSI/ASME B18.21.1