Many people use chains for securing or connecting objects, but most do not understand the properties of the chains they are using. They just know they are strong and usually do the job. However, in a job where you're using a chain to secure a large mass, it's imperative to know that the chain will hold up. Tensile load is the force that is pulling on a chain. A simple, scientific experiment will figure a chain's ultimate tensile strength -- the amount of weight the chain will bear before breaking. This can also be a fun and informative way to introduce kids to science by using small diameter chains.
Things You'll Need
- Weights of varying masses
- Metal bucket
- Two metal hooks (must be stronger than the chain)
- Protective goggles
- Workman gloves
Find a suitable area to carry out your experiment. If you are using a small gauge (measured in inches or millimeters) chain, your garage will be suitable. But testing for the ultimate tensile strength of larger chains should only be conducted in laboratories or other commercial areas where the proper safety precautions can be observed.
Connect one of the metal hooks to a metal or wood beam that will bear the weight of the masses you will add. The beam should be horizontal to and high enough above the ground to accommodate the length of chain you will test and the metal bucket.
Connect the chain to the metal hook. You can either test the length of chain that will be used in the intended application, or you can test a smaller length of chain for experimental purposes.
Weigh the metal bucket and hook before attaching it to the chain. Notate on a piece of paper how much each weighs. Be sure to keep a running log of all your measurements.
Add variable masses to the bucket until the chain breaks. The masses can be any object that has a given weight. For the purposes of home testing, weights from a gym or lead shot are useful.
Add all the weight (bucket, hook, added masses) together. This will give you the maximum load any given chain can bear.
Tips & Warnings
- This experiment is repeatable with any type of material such as string and wire.
- Although standard weight (ounces and pounds) can be used, proper scientific experiments are conducted using the metric system (grams, kilograms).
- Testing chains that bear heavy loads require extra safety precautions such as body armor or testing using machines. When broken, these chains can act unpredictably and cause major damage to your person or property.
- Photo Credit chain image by Pefkos from Fotolia.com
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