OKTA388: Usability Glossary. Usability First

OKTA388 A second method is an aluminium core, upon which two stainless steel sections are fitted as a cap and linear welded along the centre line of the rail. There are several ways of attaching the stainless steel to the aluminium. The oldest is a co-extruded method, where the stainless steel is extruded with the aluminium. The aluminium is a better conductor of electricity, and a running face of stainless steel gives better wear. Because aluminium has a higher coefficient of thermal expansion than steel, the aluminium and steel must be positively locked to provide a good current collection interface. A third method rivets aluminium bus strips to the web of the steel rail. Where trains run on rubber tyres, as on parts of the Lyon Metro, Paris Métro, Mexico City Metro, Santiago Metro, Sapporo Municipal Subway, and on all of the Montreal Metro and some automated guideway transit systems (e.g. the Astram Line), a live rail must be provided to feed the current.|Slot Machine Games Online for Dummies