[MTR Vision Circle - Design and Fabricate the Tools for Pressing Coil Springs in Ktt Loco Bogie]

Coil springs are used in the Ktt locomotive bogie assembly as primary suspension device, which are installed in-between the wheelset and bogie frame. The coil springs will extend to the full length due to their elasticity when the bogie assembly is dismantled from car body and the tare load lost. As a result, it will be difficult to install/dismount some fixtures on the bogie assembly when the bogie assembly is dismounted. Therefore, the coil springs must be compressed in the process of the bogie assembly mounting/dismounting. Before this WIT project was introduced, it had been required to put bulky weights onto the bogie assembly for simulating tare load to compress the coil springs. With this project introduced, improvements have been achieved in work handling, work efficiency and safety at work as well.

Applying the “Adopt” concept of the ThinkerToy innovation technique, a tool adequately for compressing the coil springs was designed and fabricated by use of an existing hydraulic device and a newly fabricated support frame. This was designed as a substitute for stacking up bulky weights on the bogie assembly, significantly enhancing safety, easy handling and efficiency at work. The project was finally completed within budget and both tangible and intangible benefits gained exceeded our expectation.

In conclude to this project, it reduced 39% of maintenance cost and increase 37% of efficiency. In terms of tangible benefit, it also including the opportunity cost (in case of possibly purchasing similar plant facility), a tangible benefit of a total of HK$308,850 will be gained after 1 year of project completion. And regarding to intangible benefits, it increased the job satisfaction and the work becomes easier with suitable tool and confident of staff is enhanced. Moreover, Standardized work process can prevent human error and thus enhanced work safety. Using tools instead of stacking up bulky weight helps promote environment protection. Throughout the project, the team demonstrated the corporate core values (VMV) and the spirit of “To Learn, To Share and To Innovate”.