Protection of the tracks

The sleeper anchor

Sleeper anchors are made from spring steel and therefore offer a friction-based connection. They are removable and reusable after a long service life, since they are made of high quality material. The sleeper anchor can, depending on the track situation, be fitted either in the track axis, or on the sleeper ends. So-called safety caps are mainly used on the sleeper ends to increase the lateral sliding resistance.
The installation and removal of the sleeper anchor is quick and easy at any position of the sleeper and can be done without removing a lot of ballast beside and below the sleeper.
During rework or compressing and lining, the sleeper anchor can simply be released, and after tamping fastened down again. The releasing and tightening is done by means of a power wrench or a manual spanner.
The increase of the lateral displacement resistance takes effect immediately after the installation of the sleeper anchor.
The sleeper anchor gives sufficient safety (against twisted track) even at critical places on continuously welded track.

by Thorsten Schaeffer
Regular arrangement of sleeper anchors
© Thorsten Schaeffer
Installed sleeper anchor in detail
Verbauter Schwellenanker im Detail
© Thorsten Schaeffer

The safety cap

The installation and removal of safety caps at the end of the sleeper is quick and easy and can be done without removing a lot of ballast beside and below the sleeper. There are safety caps for each type of sleeper (wood, concrete and steel sleepers). They differ in the shape and the installation instructions, since not all are fitted at the same position on the sleeper end. During rework or compressing work and lining, the safety cap can simply be released and fastened down again after tamping. The releasing and tightening is done by means of a manual wrench.

The increase of the lateral displacement resistance works immediately after the installation of the safety cap. The safety cap is not like the sleeper anchor in the middle of the sleeper but is always fitted on the sleeper end on the inner side of the curve.

Both safety measures (sleeper anchor/safety cap) may be fitted, among other places:

  • In turnouts.
  • In track curves.
  • If the permissible speed in curves has been increased.
  • In transition from bridges to embankment.
  • In areas where there is mining subsidence.
by Thorsten Schaeffer
Sleeper anchor on end of sleeper
© Thorsten Schaeffer

You can find suitable specialist literature to the topic here:

The Basic Principles of Mechanised Track Maintenance

The Basic Principles of Mechanised Track Maintenance

This book is dedicated to the many people involved in the day to day planning and performance of track maintenance activities. Providing a practical approach to everyday challenges in mechanised track maintenance, it is not just intended as a theoretical approach to the track system. 
Railways aim at transporting people and freight safely, rapidly, regularly, comfortably and on time from one place to another. This book is directed to track infrastructure departments contributing to the above objective by ensuring the track infrastructure’s reliability, availability, maintainability and safety – denoted by the acronym RAMS. Regular, effective and affordable track maintenance enable RAMS to be achieved.

Best Practice in Track Maintenance, Vol 1 - Infrastructure Management

Infrastructure Management Volume 1 looks at aspects of infrastructure management with particular reference to the single European railway area. Based on best-practice examples from Central Europe, measures for the targeted retrofitting and improvement of the infrastructure maintenance of the existing network are presented. In many cases, infrastructure operators are faced with a generational change, which accelerates the process. Modern information and communication technology can simplify the comprehension and presentation of complex contexts. Modified approaches to asset management and life-cycle management enable implementation of the "transparent permanent way" or the "railway 4.0".