Railway rails
Rails are steel profiled rolling products in the form of strips. The last GOST R 51685-2000 for rail rails provides for four types of rails P50, P65, P65K (for curves) and P75, the quality categories provide rails:
B - high-quality heat-strengthened;
T1 and T2 - heat-strengthened;
H - non-heat-strengthened.
In the new GOST, a special rail, P65K, has been introduced for laying out curved sections of the road into the outer rail threads. The main difference lies in the outline of the head. The lateral faces of it in the upper part have a slope of 3.5: 10, which reduces the intensity of lateral wear of the rails.
The rails are subject to a number of requirements:
· Straightness in the vertical and horizontal planes must be ensured;
· Tolerances in the dimensions of the transverse profile are established;
· Chemical composition and hardness of rail steel are determined;
· Non-permissible defects in metallurgical production and non-metallic stitch inclusions are stipulated, etc.
The finished rails at the factory are subject to acceptance, continuous defectoscoping and branding. On the neck along the axis of each rail (on the same side where convex signs are rolled out) hot dip number is applied in 2 places along the length of the rail at a distance of not less than 1.0 m from its ends (the melting number of the rails of group 1 must begin with Letters P); Designation of the serial number of the rail.
Stamps applied to the neck of a hot rail should be 12 mm high and deepened into the body by 0.8 ... 1.5 mm. The distance between the signs should be 20 ... 40 mm.
As the tonnage is increased, various damages, deformations, fatigue defects, etc. accumulate in the rails.
|
The name of the upper track material |
Function |
GOST, OST, TU |
Drawing |
|
R50 rails |
Used for a railway with a freight intensity of 25 to 75 million tons per km / km per year. |
GOST R 51685-2000 |
|
|
R65 rails |
Used for railways with a freight intensity of 10 to 25 million tons per kilometer / km per year. |
GOST R 51685-2000 |
|
|
P43 rails |
Used on the routes of industrial enterprises. |
GOST R 51685-2000 |
|
