Investigation into the feasibility and application of composite materials in conveyor support structures for use in underground coal mines

摘要

Composite materials are well-renown for their strength to weight ratios and are widely used in many industries where high strength and low weight is required. Although steel is the traditional material of choice in the mining industry, and particularly for conveyor support structures, the strength and weight advantages offered by composite materials has prompted this investigation into the feasibility of using composite materials in underground mining conveyor support structures.The first phase of the project centred on establishing and applying selection criteria for the materials and processes which could be used in such a structure. Key concerns include fire performance, electrical conductivity, cost, availability and manufacturability. Based on these considerations, the project identified a phenolic-glass laminate manufactured using the RTM method (for moulded components) or the pultrusion process (for tube sections) as a possible basis for a composite conveyor support structure.The second phase of the project developed a set of design criteria for the use ofcomposite materials in conveyor support structures and a series of preliminary designs based on current conveyor configurations. After analysing each preliminary design against key design criteria, in particular cost, weight, assembly time, susceptibility to damage and torsional loading, the Linestand Suspended - Beam configuration was selected as the preferred option.The third phase of the project used the findings of the preliminary design analysis and the key design criteria to develop a prototype final design. The prototype design is based on a hybrid style of frame. The majority of the structure is constructed from a custom pultruded beam connected with a composite connection piece, while theinterface between the rollers and the frame utilises a steel bracket to reduce the risk of damage to the composite frame. The final design is 12kg lighter than the currentsmaller steel design of similar function.The project has demonstrated the feasibility of using composite materials in conveyor support structures and the weight savings that may be achieved.