Essential Considerations 

• -identification and assessment of geological conditions
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• -consideration / modification of machine diameter
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• -bearing condition (check, maintain, replace, spare)
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• -electrical wiring (check, replace)
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• -drive motors (test, rewind, replace)
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• -hydraulic system (test, refurbish)
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• -hydraulic hoses (replace)
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• -electric motors (test, rebuild)
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• -programmable logic chips [PLCs] (check, re-program)
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• -re-builder's warranty