Rail grinding extends the railway service life

Why rail grinding is needed ? and normally which parts of the rail need to be ground?
Rail grinding is a necessary maintenance activity performed on railway tracks to ensure safe and efficient operations. It involves the of specialized grinding machines to remove irregularities, defects, and wear from the railhead.
There are several reasons why rail grinding is needed:
1. Corrective Grinding: Over time, the railhead can develop irregularities such as surface cracks, corrugations, and spalling due to heavy traffic loads, temperature variations, and other factors. These irregularities can lead to increased noise, vibration, and wear on the train wheels. Grinding helps to correct these defects, reducing noise levels and improving passenger comfort.
2. Fatigue Life Extension: Regular grinding can extend the fatigue life of the rail by removing surface cracks and preventing their propagation. This helps to prevent rail breaks, which can cause derailments and other safety hazards.
3. Rail Profile Restoration: Continuous use of the tracks can result in a loss of the desired rail profile, creating an uneven running surface. Grinding restores the original rail profile, ensuring smooth and stable train movements.
4. Wheel/Rail Contact Optimization: Grinding can adjust the wheel/rail interface to ensure proper contact between the two surfaces.
A well-maintained profile reduces friction, wear, and rolling resistance, resulting in energy savings and improved train performance.
The parts of the rail that are commonly ground include:
1. Railhead: The top surface of the rail, which comes in contact with the train wheels
2. Gauge Face: The inner side of the railhead, which faces inward towards the track center
3. Field Side: The outer side of the railhead, which faces outward towards the track perimeter
The last picture is some grinding machine which can help it, for more information, please contact with me further.