Sandite

Sandite is a substance used on railways in the UK, Ireland,US, the Netherlands and Belgium to combat leaves on the line, which can cause train wheels to slip and become damaged with flat spots. Sandite consists of a mixture of sand, aluminium and a unique type of adhesive.

Leaf build up on the railhead can also cause signalling issues and 'disappearing trains' on the rail control systems (because of the electrically insulating effect of the leaves, which can prevent operation of track circuits).

British Rail conducted research, in 1976, to determine the suitability of Sandite for use as an adhesion improver.

Sandite is usually applied by a special train which first clears fallen leaves from the rails using high-pressure water, then sprays the sandite onto the rail surface. In order to assist the staff on the Sandite train in locating the sites concerned, in England and Wales black on yellow lineside markers were installed:

From 1992, lineside marker boards were installed on the Scottish Region, based on alternative white octagonal boards to denote the commencement and finish points, with no warning sign.

In The Netherlands, Sandite is applied by the first passenger trains of the day, with special maintenance trains available too.

Multiple units used for this have included:

English Welsh & Scottish Railways and Weedfree Limited provide locos, drivers and equipment operators for the Autumn treatment circuit.

Direct Rail Services provide locomotives for loco-hauled stock.

Northern Ireland Railways currently uses a withdrawn NIR Class 80 multiple unit as their sandite train.

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Wikipedia