ÖNORM EN 15551

This document defines the requirements for buffers with 105 mm, 110 mm and 150 mm stroke for vehicles or units which use buffers and screw coupling. It covers the functionality, interfaces and testing procedures, including pass fail criteria, for buffers. It defines the different categories of buffers, the space envelope, static and dynamic characteristics and energy absorption. It defines the static and dynamic characteristics of the elastic systems. It also defines the requirements for buffers with integrated crash elements (crashworthy buffers) for tank wagons for dangerous goods. The requirements of this document also apply to buffers of locomotives and passenger coaches which are bound to meet the crashworthiness requirements of EN 15227 for normal service only. The properties for the energy absorbing function are defined in EN 15227 and the requirements specified in Clause 7 for tank wagons for dangerous goods are not applicable to the buffers of these locomotives and passenger coaches. Diagonal buffers are excluded from this document. For the crashworthy buffers of locomotives, driving trailer or passenger coaches according to EN 15227, and tank wagons for dangerous goods or buffers which form part of a combined system consisting of a special buffer and a deformation element, interchangeability with freight wagon buffers is not required, and therefore the requirements of 5.3 (Buffer dimensions) do not apply, those of 5.4 (Mechanical characteristics of buffers) and 5.6 (Marking) apply with restrictions. Provisions going beyond the scope of this document may be agreed in the Technical Specification. The Technical Specification is not a mandatory document.