DCD has been receiving many requests regarding our breakaway pins in permanent or semi-permanent installations. Originally designed as a single use pin, this product has found its way into various applications where general overload protection is required. However, as parts get pulled, pushed, bent, or otherwise loaded, they start to fatigue, which eventually results in a lower break strength. Designing for fatigue isn’t always complicated. This is one of the reasons we have safety factors on our equipment – to ensure excessive damage does not occur during typical usage that would cause a premature failure. Applying a safety factor to a breakaway pin doesn’t apply, though, since you want it to break at a certain load, not any higher.
To help out our customers, DCD has developed a torque table for tensile breakaway pins, intended for the tensile pins used in our 00560-010 and 00560-020 breakaway connectors. By installing your breakaway pin torqued to the values specified, you can apply a preload and avoid any cyclic loading on your pin, reducing fatigue and giving it a longer life, without affecting the break load in a longer term installation. These torques are what we recommend as a limit to prevent damage to the pin, based on our test results.
|Connector||Kit Part No.||Target Break Load
|Target Break Load
Example: A pin from the 00565-200 pin kit will break at 2000 lbs. Your application sees vibration, loading and unloading up to 1000 lbs on a regular basis. When you install the pin, torque it to 68 inch-lbs and your pin will not see any wear and tear from loads or vibration applied below 1360 lbs.
These values provide a maximum recommended torque based on our calculations and tests that will provide a preload on the pin. When under cyclic loading, the pin will not ‘feel’ loading under the preload value, thereby extending the life of the pin significantly. However, we do recommend that if you use the breakaway connector in a longer term installation, be sure to apply periodic inspections or replacement based on your operating conditions, since corrosion (due to salt water, for example) will also corrode the pins and cause premature failure of the pins over time. Also consider our stainless steel pins. For more information regarding your specific application and the suitablility of our pins, feel free to contact our engineering department.