The Benefits of 420 Chrome Stainless Steel Coiled Spring Pins

In applications requiring a combination of high strength, superior fatigue life, and corrosion resistance, 420 martensitic chrome stainless steel offers a host of technical benefits and provides an overall robust cost-effective solution.


An automotive molder was molding and assembling an Oil Level Dipstick consisting of a blade and finger ring. Their objective was to be able to quickly and efficiently assemble 5,000 units per month. To do so, the company desired to establish a production cell that could accomplish this in one week. The cell also needed to be flexible enough to allow them to assemble several other low-volume items in the remaining weeks of each month.
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Coiled Pin and Model PM manual pin inserter

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Alignment fixture for ease of assembly

A standard-duty SPIROL® Coiled Spring Pin was selected to permanently fasten the two components together. SPIROL’s Application Engineers worked with the molder to determine that five SPIROL Model PM Manual Pin Inserters equipped with spring-loaded alignment pin fixtures would accomplish their goal. Each SPIROL Model PM machine can be easily and quickly converted from one pin size to the next by swapping pin chucks and alignment fixtures. Various assembly sizes are accommodated by raising and lowering the mechanism head without the need for tools.

The Model PM machines provided the molder with the ability to deliver quality assemblies and the flexibility to meet the work cell’s production goals.

Our staff of engineers will review your application needs and work with your design team to recommend the best solution.

Need help finding the right solution?

SPIROL offers complimentary Application Engineering support. We will assist on new designs as well as help resolve issues, and recommend cost savings on existing designs.