What is rail wear ? How to measure it ?

1. What is Rail wear?

(1) Side wear

Side wear occurs on the outer strand of the small radius curve and is one of the main types of damage on the curve. When the train runs on the curve, the friction and sliding of the wheel rail is the root cause of the side rail grinding. When the train passes a small radius curve, there will usually be two points of contact between the wheel and the rail, and the side grinding occurs most. The size of the side grinding can be expressed by the product of the guiding force and the impact angle, that is, the wear factor. Improve the conditions of the train passing curve, such as the use of wear-type wheel treads, the use of radial bogies, etc. will reduce the rate of side grinding.

From the perspective of engineering, the material of the rail should be improved, and wear-resistant rails should be used. For example, the high-hard-earth rail has a wear resistance of about 2 times that of a common rail and a quenching rail of more than 1 time.

Strengthen the maintenance and repair, set the appropriate gauge, the outer rail super high and the rail bottom slope, increase the flexibility of the line, apply oil on the side of the rail, etc., can reduce the side wear effect.

(2) Wave wear

Wave wear refers to the wave-like uneven wear on the top surface of the rail, which is essentially a wave-shaped crush. Wave grinding will cause high wheel-rail dynamics, accelerate damage to rolling stock and rail components, and increase maintenance and repair costs. In addition, the train's severe vibration will make passengers uncomfortable. In severe cases, it will also threaten driving safety. origin of. Some freight lines in China have experienced serious waves. Its development speed is faster than side grinding, which is the main reason for the change of rail.

The wave grinding mainly occurs on heavy-duty transportation lines, especially on coal transportation and transportation lines. It also occurs in different degrees on high-speed high-speed passenger lines, and is also common in urban subways. There are many factors affecting the development of rail wave grinding, which involve many aspects such as rail material, line and machine conditions. The dynamic effect is the external cause of the formation of the rail wave, and the material properties of the rail are the internal factors of the wave grinding. In fact, it is quite difficult to summarize all the causes of rail wave grinding by analyzing only one aspect. It is necessary to use vehicles and tracks as a system to study the formation of various vibrations and conduct multi-faceted and multidisciplinary research on the whole. In order to grasp the full picture of the cause of the wave.

Polishing rails is now the most effective way to eliminate wave grinding. In addition, there are some measures to slow down the development of wave grinding: use continuous welding to eliminate rail joints and improve track smoothness; improve the material of rails with high-strength wear-resistant rails, improve the quality of heat treatment process, eliminate residual stress of rails; improve track quality Improve the elasticity of the track and make the longitudinal and transverse elasticity continuous and uniform; keep the curve direction straight, the ultra-high setting is reasonable, the outer rail working side is oiled; the wheel-rail system should have sufficient resistance.

2. How to measure rail wear?

Lianjie mechanical&electrical co.,ltd has one kind digital rail wear gauge  to measure rail wear include lateral wear and vertical wear. Easy to operate with high accuracy. 

3.Special advantages of Lianjie digital rail wear gauge 

1. Digital type with direct readings: LCD display screen, clear and readable; No calculations required,gives direct reading ; When reading, hold down the HOLD button to fix the measurement value and facilitate reading.

2. High measuring accuracy: The measurement accuracy is 0.01m

3. Easy to use, measure the vertical and lateral rail wear at the same time: position the rail wear gauge on the outer side of the rail .

Push the vertical and lateral rail wear gauge so that the measuring probe is in contact with the upper surface and inner side of the rail respectively.Then the vertical and lateral wear of the rail can be read.

4. metric /imperial unit

5.Support customize:we could customize all kinds wear gauge according to different rail profiles and different measure points.

6.Fast calibrate:One-key zero clearing function, can be quickly calibrated before each use to reach the factory measurement accuracy.

7.Magnetic fixed part: strong magnetic fixed part to attach to the rail.

8.Rail fillet as measuring base to ensure measure data more accuracy: Rail fillet is more clear than rail bottom,no dust. It could ensure the measure result reliability.

9.Portable Handle ：This product is designed with a handle that is easy to hold, which greatly improves the portability of the product. It can avoid touching the ruler body directly, cause the ruler body to be stained and corroded, improve the product service life.

10. Good stability and high strength of the material

The ruler body is made of 3cr13 stainless steel. After the heat treatment, it has higher strength and hardness, not easy to deformation, it has a good stability.

11. We can customize the matching inspection tools