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www.marinelink.com 97Static load testing is an essential part of many engineering, building and man-ufacturing businesses ? and the ship-ping, marine and offshore industry is no exception. Water Þ lled weights (also known as ballast bags) provide a ß exible method for load testing. Test weights must be sufÞ ciently heavy to ascertain the maximum load of an object, but they should also be reusable and safe to de-ploy in a test environment. Where there is easy access to a plentiful supply of water, water- Þ lled weights can provide a quick, efÞ cient means to undertake such testing. When empty the bags weigh a small fraction of the Þ lled weight (typi- cally less than 1% of their capacity) ? and can be packed into transit crates, making them easy to deploy and pack down again for storage between jobs. In use they can be partially Þ lled for any exacting requirements, or used in com-bination to achieve larger test capacities. Once Þ lled with water, these bags will generally weigh anywhere from 1,000 Kg to 50,000 Kg. Larger sizes are pos- sible, but beyond 50t the handling ben-eÞ ts start to diminish. Objects can be tested in various ways: for example, test weights might be attached to the center of a steel arch to ascertain load capacity before being (vertically) afÞ xed to one end to test tensile strength. Understand-ing how components, parts or materials behave under extreme loads in different positions can help engineers create safer and more powerful systems.Although capable of being used al-most anywhere, water- Þ lled weights are often deployed in docks to ensure that parts can be tested without fear of causing structural damage (failed com-ponents and the weights attached to them can simply fall into the water). To ensure that materials are tested accurately, the risk of cable failure is reduced by the in-clusion of telemetry dual-load shackles and tensile load cells. There are no glob- ally-recognized standards governing this Þ eld of work, but the nearest are the 051 Guidelines as developed and published by the Lifting Equipment Engineers As- sociation (LEEA) ? a U.K. body which is gaining increased worldwide rec-ognition. Its 051 Guidelines cover the design, inspection and use of such bags as test weights within the offshore and marine industries ? and focuses in par- ticular upon subjects such as component suitability and traceability, manufactur- ing test regimes, and the desirability of having drop-tested bags of each size to prove that they are capable of withstand-ing a peak load of 6x their capacity, or working load limit. Unique Maritime Group?s Unique Sea ß ex is at the fore- front of being able to demonstrate com-pliance to these LEEA guidelines. Work- ing within the limitations of the largest test rig it could Þ nd, all of its water bags have proven themselves capable of with-standing overloads many times in excess of their working load limits ? with Type Test Certi Þ cation and Product Design Assessment CertiÞ cation from ABS by way of independent veriÞ cation of the integrity of their designs. www.uniquegroup.com Dockside Load Testing with Unique Seaß exMR #8 (90-97).indd 97MR #8 (90-97).indd 978/7/2014 10:04:47 AM8/7/2014 10:04:47 AM
