ISO/TC 269/SC 2/WG 1 - Railway braking

This document defines terms for brakes and braking in rolling stock.

This document defines the quality classes of compressed air produced by air generation and treatment units (AGTUs) and/or used in pneumatic apparatus and systems of rail vehicles. This document is applicable to compressed AGTUs and also to all pneumatic equipment and systems of rail vehicles.

This document specifies the methodologies for calculation of braking performance for railway rolling stock. This document describes the general algorithms/formulae using instantaneous value inputs to perform calculations of brake equipment and braking performance, in terms of stopping/slowing distances, braking power and energy for all types of rolling stock, either as vehicles or units. The calculations can be performed at any stage of the assessment process (design, manufacture, testing, verification, investigation, etc.) of railway rolling stock. This document does not set out specific acceptance criteria (pass/fail). This document is not intended to be used as a design guide for the selection of brake systems and does not specify performance requirements. This document does not provide a method to calculate the extension of stopping distances when the level of demanded adhesion exceeds the available adhesion (wheel slide activity). This document contains examples of the calculation of brake forces for different brake equipment types and examples of the calculation of stopping distance for vehicles or units.

This document specifies methodologies for calculation of braking performance for railway rolling stock and is applicable to all countries. This document describes the general algorithms/formulae using mean value inputs to perform calculations of brake equipment and braking performance in terms of stopping/slowing distances, stationary braking, power and energy for all types of rolling stock, either as single vehicles or train formations, with respect to the braking distance. The calculations can be used at any stage of the assessment process (design, manufacture, testing, verification, investigation, etc.) of railway rolling stock. This document does not set out the specific acceptance criteria (pass/fail). This document is not intended to be used as a design guide for selection of brake systems and does not specify performance requirements. This document does not provide a method to calculate the extension of stopping distances when the level of available adhesion is exceeded (wheel slide activity). This document contains examples of the calculation of brake forces for different brake equipment types and calculation of stopping distance and stationary braking relevant to a single vehicle or a train.

This document provides additional information to assist the understanding and the use of ISO 20138-1. The calculations in this document follow the same principles but they are slightly different. This document contains country specific calculation approaches currently in use and represents the state of knowledge including for calculating: — stopping and slowing distances; — equivalent response time; — brake performance; — brake ratio.