scope:

This specification sets out the performance requirements for processes for the cold expansion of fishbolt holes using the split sleeve method.

PURPOSE

To ensure that the methods, tooling and consumables used for the cold expansion of fish-bolt holes using the split sleeve process generate the required level of compressive residual stress around the periphery of the bolt hole and will not give rise to spurious echoes when examined ultrasonically. In addition, to ensure that the risk of rail splitting during the cold expansion process is minimal and that the risks to staff as a direct result of the use of the process are negligible.