In the field of railway construction, GB heavy rail specifications are crucial, which are directly related to the bearing capacity and operation safety of the railway. Heavy rails, usually referring to rails with a nominal weight greater than 30 kg per meter, are a key component of the track for heavy vehicles. According to GB standards, common heavy rail specifications include 38kg/m, 43kg/m, 50kg/m, 60kg/m and 75kg/m.
| Rail Type | SIZE(mm) | theoretical weight | |||||||||
| height | bottom width | head width | waist depth | ||||||||
| Heavy rail | 38KG | 134 | 114 | 68 | 13 | 38.733 | |||||
| 43KG | 140 | 114 | 70 | 14.5 | 44.653 | ||||||
| 45KG | 145 | 126 | 67 | 14.5 | 45.546 | ||||||
| 50KG | 152 | 132 | 70 | 15.5 | 51.514 | ||||||
| 60KG | 176 | 150 | 73 | 16.5 | 60.64 | ||||||
From the parameter details, taking P50 rails as an example, it weighs 51.514kg per meter, is 152mm high, has a rail head width of 70mm, a rail bottom width of 132mm, a rail belly thickness of 15.5mm, a bolt hole diameter of 31mm, and a center distance of 66mm from the rail end to the first hole. The P60 rail weighs 60.64kg per meter, is 176mm high, has a rail head width of 73mm, a rail bottom width of 150mm, a rail belly thickness of 16.5mm, and a bolt hole diameter of 31mm, but the center distance from the rail end to the first hole is 76mm. The difference in size between rails of different specifications determines their respective applicable scenarios.
In actual applications, 60kg/m and 50kg/m rails are widely laid on the main railway lines to meet the operation needs of conventional trains. Station lines and dedicated lines are generally laid with 43kg/m rails due to the relatively low frequency and load of trains. For heavy-duty railways and particularly busy sections of railways, 75kg/m rails are the first choice due to their stronger bearing capacity because they have to bear greater train loads.
The standard length of rails is clearly specified in the GB standard, mainly 12.5m and 25.0m. Extra heavy and heavy rails mostly use 25.0m standard length rails to reduce the number of rail joints and reduce the impact of train operation. Other types of rails can flexibly use 12.5m or 25.0m standard length rails according to actual conditions. In the curved track section, in order to adapt to the curvature of the line, shortened rails are also used, such as three types that are 40, 80, and 120mm shorter than the 12.5m standard rail, and three types that are 40, 80, and 160mm shorter than the 25.0m standard rail.