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Several hydraulic poppet/solenoid valves that utilize Coiled Spring Pins

Diagram showing how the Coiled Spring Pin retains the check ball in the valve

Coiled Spring Pins provide combinations of strength, flexibility and diameter to meet the specific engineering objectives of your pinning applications.

Coiled Spring Pins
Application: Hydraulic Poppet / Solenoid Valve

The customer was looking for a pin to be used in a hydraulic poppet valve. The pin is used to retain a check ball from falling out of the valve as a result of preset hydraulic pressure and flow. While working with the customer early in the design stage, SPIROL’s engineering team noticed that the poppet is subject to longitudinal shock forces. After evaluating several pinning options, SPIROL recommended the optimal Coiled Spring Pin for a perpendicular installation to prevent the ball from coming loose. Unique characteristics of the Coiled Spring Pin provided the flexibility needed to absorb shock loads and enough strength to withstand forces generated.

The Coiled Spring Pin met all the performance criteria required by the customer and resulted in component and manufacturing cost savings versus the more traditional (and expensive) fastening method. Traditionally a check ball is retained in the poppet valve by using a threaded collar with a threaded fastener. Not only is this expensive (because of the threading step), it also means added assembly time versus the more modern/innovative way of using a Coiled Spring Pin by simply pressing it through a cross drilled hole to hold the check ball in place.

Hydraulic poppet valves are used to control the timing and quantity of liquid flow. As these valves are used in critical applications such as canal locks in community infrastructure and various commercial vehicles, it is very important to ensure that all components used in the valve function as desired to meet the stringent application requirements. Since SPIROL was able to work with the customer early in the design stage, they were able to recommend the appropriate hole sizes, engagement length, material type, and finish for the Coiled Spring Pin to function properly in the application, helping to keep the customer’s design project progressing within their original timeline.

Even though the pin is often one of the smallest and least expensive components in an assembly, it is critical to design in the optimal pin configuration to ensure proper operational and functional excellence at the lowest installed cost. With over 60 years of technical expertise related to joining and assembly, SPIROL is well positioned to assist with design of the pin to ensure their customers’ parts go together and stay together for the intended life of the assembly.

Our staff of engineers will review your application needs and work with your design team to recommend the best solution.  One way to start the process is to select Pinning Applications in our Optimal Application Engineering portal.

Many other applications can be reviewed in the private area of our web site.  In addition to application examples, registered users gain access to convenient online services and information not available on our public website.  To gain access, Register now.