The EMU bogie is a significant apparatus in the TIAA MRT System that supports the vehicle’s weight and its loading, guides the train to operate along the rail, ensures the train to pass curves and alleviates vibration and shock caused by train operation. In other words, the bogie design directly determines the stability and comfort of the EMU.
The components of the apparatus consisted of the bogie frame, bolsters and relevant devices. The bogie frame is made from welding the left and right side girders and the central beam together; the bolster is welded with the left and right bolster anchorages. After welding, the welded tracks have to be inspected then subjected to heat treatment, machining and painting operations. Then, the bogie will undergo visual and dimensional testing to confirm its size and sent to the bogie assembly factory to assemble related devices including pipe fittings, wheel sets, gear boxes, couplings, the traction motor, brake set, collector, fuse boxes, air springs, and the main suspension onto the bogie frame or bolster. After the bolster is combined with the bogie frame and with the final coating procedure, the bogie is finally completed.
The completed bogie needs to be subjected to visual and dimensional testing including inspecting the distance between the base level of the bogie frame and axel box, the distance between rail surface and the components with the lowest position (gear unit bottom), wheelbase measurement, height difference between the gear end and the motor side of the coupling, visual inspection of devices (traction motor, flange lubricator, odometer, speed sensor), checking whether each bolt is locked and labeled, whether compressed air piping and fastening installations are loosened, whether wire and cable fastenings are loosened, coating (appearance, thickness), functionality testing (air leakage, brake unit function, collector) and serial number verification of each apparatus. After passing the criteria, the apparatus will then be qualified to send to the vehicle assembly factory for assembly with the main body and proceed on with the subsequent assembly and testing operations.