Trelleborg Industrial AVS, the international specialist in anti-vibration and suspension technology, has won a repeat contract to supply chevron springs for bogies in use on the Singapore metro system (SMRT).
The Metalastik springs were chosen by SMRT because of their reliability and performance in the DUEWAG bogies originally supplied in 1987 through Kawasaki Heavy Industries of Japan. Over this period, Trelleborg’s low-creep materials have demonstrated exceptional service life and lower maintenance costs than competitors’ designs. The present order is for over 2,000 chevrons, of which one third will be used in the motor cars and two thirds in the trailer cars of Kawasaki C751 trains.
The Trelleborg Metalastik chevrons are robust rubber/metal laminated assemblies designed to absorb high levels of shock and vibration over an extended service life. They are fitted in pairs on either side of the axle box in the primary suspension of the bogie to guide the wheelsets in the horizontal direction and carry the static and dynamic loads. Structure-borne noise transmission is reduced by the rubber elements in the units and a rubber buffer, mounted on top of each axlebox limits the vertical deflection between the frame and the wheelset.
The C751 EMUs are built to an agreed design by two manufacturers, Kawasaki Heavy Industries and Nippon Sharyo, and are amongst the newest rolling stock on the city’s mass transit network. There are six cars to a set, with a total capacity of 1920 passengers of whom 288 are seated. They have a top speed of 90kph and feature double-skinned aluminium bodies and VVVF Insulated Gate Bipolar Transistor traction control. Power on the SMRT system is supplied by a third rail, picked up by a collector shoe at the side of the bogie frame.