Investigation of Composite Materials for Knuckle Boom Crane

Abstract

Hoisting devices, Cranes plays a vital role in the day-to-day operations in the marine sector. Cranes on the vessel, based on the mission type, are designed for various operations, an example for the type crane which is used for lifting light to medium size loads is the Knuckle boom crane. In the recent years, one of most hottest topic in the marine world is the CO2 emissions. Due to the increasing demand of reducing the CO2 emissions from the world Environmental Regulatory Bodies and the national and international governments. Moreover, steel being the primary material used in the designs, production of steel also generates CO2emissions. Secondly, In the engineering world, for designing any component, weight reduction is one of the crucial factor involved in the designing process. The crane on a vessel also contributes to the weight of the vessel, thus reducing the weight of the machinery on board the vessel adds to various benefits in the evaluating the weight and further design of the vessel. Thus formulating the objective of this report to investigate the possibility of using composite materials for a knuckle boom crane in the marine environment and to conduct a strength assessment of the same. Composite materials by nature has complex material properties, in order to understand the material behaviour, a test case is setup with a suitable test specimen, a rectangular pipe based on the cross section of the crane is selected. Different load case scenarios where applied on the test specimens and the results of test specimen using composite materials where compared with that of steel. The results from the test specimen provided a good in-sight for selecting the fiber orientations for the crane jib, the selected crane component for further structural analysis. Different jib designs are considered for performing the linear structural analysis. For the chosen composite materials, the required loads needed for analyzing the crane jib were applied and satisfactory results were obtained with a weight reduction of approximate 80%. The use of composite materials for a crane component looks promising, provided that, in addition to the strength, other factors influencing the design which are specifically connected to the composite materials are also looked into.