37 HYDRAULIC, ELECTRIC AND MECHANICAL REPAIR SERVICES; THE SERVICE OF REBUILDING MINING EQUIPMENT; THE SERVICES OF INSTALLATION, CONSTRUCTION, ERECTION, ALTERATION AND MAINTENANCE OF MATERIAL HANDLING AND PROCESSING SYSTEMS AND MECHANICAL APPARATUS; METAL FOUNDRY SERVICE TO THE ORDER AND/OR SPECIFICATION OF OTHERS; MACHINING, WELDING AND FABRICATING METAL TO THE ORDER AND/OR SPECIFICATION OF OTHERS