NR TWI 3G091 ISSUE 1 PDF

Introduction

This Track Work Instruction covers the use of ‘Sandite’.

Sandite is a glutinous mixture of sand, clay and fine steel shot designed to stick to the head of the rail to improve the adhesion of the train wheels to the rail. This is necessary when the rail head conditions are badly affected by moisture (wet/ice) or contamination especially from leaves.

Sandite is normally applied by a special train known as the ‘Sandite’ train although there are road/rail and handheld alternatives. The ‘Sandite’ train is programmed to run in the early morning to cover those routes likely to be affected by wheel slip. However, manual application is sometimes applied by hand at locations where treatment has not been achieved from the train, or if there is a local isolated problem.

Sandite is applied at pre-determined locations that are identified by yellow marker boards with black diagonal stripes. A yellow board with three black diagonals is the advance warning of an application site; two black diagonals indicate where to start applying Sandite and a single black diagonal indicates to stop applying Sandite. If there are no marker boards, Sandite must be applied according to appropriate local instructions.