High iron seamless rail is how to solve the problem of the thermal contraction account?
The rail temperature force is used on the railway line to lock the track with strong line resistance, which limits the free expansion of the rail. In our country, we use high strength bolts, gusset fasteners or elastic fasteners to restrict the rail. In order to reduce the temperature force of the rail, the line should be locked when the rail is at the right temperature. The local maximum rail temperature is used to lock the rail temperature with the lowest rail temperature above the average height.
The thermal expansion and contraction of the rail of the jointless track with long rail links adopts a temperature force transfer structure, which transfers the thermal force produced by the expansion and contraction to the side track instead of accumulating on the seamless rails.
The seamless line is divided into a fixed area, expansion area, buffer, the buffer can be reserved for the large number of rail joints for expansion, expansion area adjacent to the buffer, if the buffer rail gap due to seasonal changes is not enough, the rail to replace the different length in the expansion area to adjust the rail gap.
There is a direct relationship between changes due to temperature stress in CWR under the size and temperature of rail, so we locked rail must be correct, reasonable selection of locked rail temperature, to ensure the CWR winter break, summer is not caused by track swelling, endanger traffic safety.Seamless rail to solve the heat up, cold contraction, light by a small number of cracks is not enough, and now solve the heat up, cold contraction, there are two ways. One is the long rail itself to bear all the temperature stress, the long rail is locked on the sleeper, so that it does not shrink due to temperature changes. This method applies to areas where the temperature varies slightly throughout the year, for example in southern china. In some temperature difference regions should take another approach, namely the long rail itself does not bear the temperature stress, and stress or regular bleeding stress to automatic bleeding, make the long rail with temperature rise and free shrinkage, at the time of laying also try to choose the best temperature of laying the rail expansion value in the minimum range, so that regardless of temperature rising or falling, the rail expansion always control in the smallest range.
