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Blonde Girl Strips Her Red Underwear On The Railway
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As an alternative to the insulated joint, audio frequency track circuits can be employed using a tuned loop formed in approximately 20 m of the rail as part of the blocking circuit. Another alternative is the axle counter, which can reduce the number of track circuits and thus the number of insulated rail joints required.
Continuous welded rail
Most modern railways use continuous welded rail (CWR), sometimes referred to as ribbon rails. In this form of track, the rails are welded together by utilising flash butt welding to form one continuous rail that may be several kilometres long, or thermite welding to repair or splice together existing CWR segments. Because there are few joints, this form of track is very strong, gives a smooth ride, and needs less maintenance; trains can travel on it at higher speeds and with less friction. Welded rails are more expensive to lay than jointed tracks, but have much lower maintenance costs. The first welded track was used in Germany in 1924 and the US in 1930 and has become common on main lines since the 1950s.
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