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Our customer is a worldwide service provider of lifting equipment for marine applications. They were engaged with design and realization of a customized A-Frame with lifting capability of 9-tons. The A-Frame needs to operate at different swing angles from -30 degrees to 45 degrees. In addition to the payload, the A-Frame needs to withstand wind loads and should be able to operate under extreme weather conditions. Due to the scarcity of time, customer decided to engage an external group with prior experience to accomplish the tasks of design and analysis.

Zeus Numerix exploited its vast experience in conceptual design, structural analysis and design verification studies to carry out the design for the given requirement. The design calculations conformed to the standards of Germanischer Lloyd (Guidelines Document for the Construction and Survey of Lifting Appliances). The theoretical stress calculations are validated using FEA. All the components were individually analyzed and the critically stressed regions were strengthened.

Left: Typical A Frame Model. Right: Stress distribution plot at -30° swing.

Customer was provided the detailed manufacturing drawings and supporting design and analysis documents. Upon successful acceptance, the design was scaled down for 6 tons and 3 tons load carrying A-Frames. The engagement model with Zeus Numerix ensured design of A Frame within stipulated time and budget.