Fabrication of a Steel Washer for the Automotive Industry


The serrated flat washer shown here is used in many high volume automotive applications. Composed of SAE 1050 steel, it features dimensions of 26.75mm to 27.25mm of outside diameter, 11.1mm to 11.3mm of inside diameter, and 2.95mm to 3.25mm in height.

This customer needed to quickly find an alternate source to manufacture this product, their previous supplier was not able to cleanly coin the serrations in the washer. They were utilizing a non-knuckle joint press; this method does not allow enough time for materials to flow into features such as serrations, small radius, ball or taper grooves, all of which are features ART offers. The washers looked okay but as they ran parts, the crispness of the embossment (coin) would wear off. This required constant maintenance of the tool, not allowing them to meet the volume required. Because of our advanced coining capabilities we were ability to eliminate all of these issues.

Our production utilized a 150 ton straight side stamping press for blanking, and our 600 ton knuckle joint/embossing press. We currently manufacture 10 million of these parts per year for this customer, meeting all of their requirements for quality and volume. High volume precision metal stamping for the Auto Industry is ART Metals’ sweet spot. For more information see the table below or contact us directly.

Highlights of this Precision Coin Stamping Project

Product Description

Serrations in washer grip the mating part during assembly
Applications Include: Automotive; Engine Blocks, Suspensions

Precision Coin Stamping Capabilities Applied/Processes

Coined Stamping

Rust Inhibiting

Equipment Used to Manufacture Part

600 Ton Knuckle Joint Press/Embossing Press
300 Ton Straight Side Stamping Press for Blanking

Overall Part Dimensions

O.D.: Ø 26.75mm – 27.25mm
I.D.: Ø 11.1mm – 11.3mm
Height: 2.95mm – 3.25mm

Material Used

SAE 1050 Steel

Additional Facts

Embossed with serrations on both sides of washer, plus I.D Chamfers.

In process testing/inspection performed

Size Testing
Dimensional Checks

Industry for Use

Automotive Industry


10,000,000 per Year

Delivery/Turnaround Time

12 weeks

Standards Met

Customer supplied print, 2D CAD Drawing

Product Name

Serrated Flat Washer