Rail Grinding Machine

Overview

A rail grinding machine is a maintenance-of-way vehicle that reconditions the running surface of the rail. In service, the rail head develops rolling-contact-fatigue cracks, corrugation, and a worn profile that increases noise and wheel wear. Grinding removes a thin layer of metal, typically a fraction of a millimetre per pass, to cut away those defects and restore a designed transverse profile. The machine is self-propelled so it can run to and from a worksite under its own power and grind continuously at a slow working speed, leaving a freshly cut rail head behind it.

The vehicle is a heavy on-track machine built on a welded Welded Steel Underframe riding on two Railway Bogie units, with a driving Operator Cab at each end so it can work in either direction. Diesel-hydraulic power runs both traction and the grinding work.

How it works

The Diesel Engine turns the Hydraulic Pump Unit units of the Hydraulic System, which supply pressurised oil to the traction drive and to every actuator on the machine. The heart of the machine is the Grinding Train: a row of Grinding Module units. Each module carries a Grinding Spindle Motor spinning an abrasive Abrasive Grinding Stone against the rail, while a Positioning Hydraulic Cylinder sets the contact angle and pressure. By combining stones at different angles across the train, the machine reproduces the full target rail-head profile in a single pass.

Grinding throws off hot metal swarf and sparks, so several support systems run alongside it. The Dust Collection System system draws swarf and dust into filters; the Water Spray System system wets the rail to cool it and quench sparks; and the Fire Suppression System system guards against lineside fires. To control the cut, the Rail Profile Measuring System scans the rail profile before and after the stones and feeds an on-board computer that adjusts module pressure and angle, while the operator supervises from the Cab Control Display in the cab.