Page 76 - 捷運技術 第43期

70 蘇培坤 捷運鋼軌鋼輪系統車輛之減噪車輪及相關技術介紹

Introduction of Noise-reduction Wheels and Related Technology

Applied to MRT Trains

Peir-Kuen Su
Abstract

The Circular line, currently under construction, will be a rapid transit system with steel
wheel trains running on steel rails with small radius curves. The route will pass through heavily
populated urban areas, so noise will surely pose an environmental problem in the near future

when the line opens for service and countermeasures should be put forward early in the planning
stage so as to reduce complaints from the general public. In particular, a new noise control
standard enacted by the EPA on January 21, 2010 stipulates that not only original average noise
(Leq) limits but also an Lmax noise limit that should be followed simultaneously. For an MRT

system with traditional steel wheel trains running on steel rails, the main sources of noise are the
construction structure, wheel-rail, motor, gear box, power pack, air compressors, air conditioning
equipment, etc. For trains running at speeds form 50km/hr to 120km/hr, the main noise source
arises from wheel-rail contact that generates vibrations from wheels, tracks, sleepers, and rail

fasteners, especially high frequency squeal sounds that arise in narrow curve areas. It is difficult
for conventional steel wheel designs to meet new noise control standards. Therefore, when
thinking about noise reduction, manufacturers must take both track and vehicle equipment into
consideration. Potential designs include damped rail, trackside lubricator, floating slab track,

damped wheel, vibration absorber, and other technologies. Being short of experience in wheel
noise reduction design, a group from DORTS visited wheel manufacturers and rapid transit
systems in Japan, Germany and Italy in September 2010 to further know about noise reduction
design and the effectiveness of damped wheels. They also made a detour to attend the Innotrans

exhibition held in Berlin to look at noise absorption and reduction technologies, and collect
relevant information. This article gives an overall introduction of the trip with the hope of
helping readers to better understand noise reduction design technology.

Keywords: damped wheel, vibration absorber