BS EN 17069-1-2019 pdf free download.Railway applications – Systems and procedures for change of track gauge Part 1: Automatic Variable Gauge Systems
5.2 Functional requirement
The design of the earthing system shall comply with EN 50153.
The requirements regarding electrical resistance as set out in EN 13260 shall be applied. If necessary,specific electrical installation can be mounted.
Vehicles fitted with variable-gauge systems shall fulfil EN 15273-1 and EN 15273-2.
6 Automatic Variable-Gauge Systems
6.1 General
The functionality of the system shall be defined at the design stage, together with its main features (e.g. how forces are received and transferred) in order to set an appropriate assessment methodology.
6.2 Functional requirements
6.2.1 Running gear
Vehicles fitted with variable-gauge running gear should be capable of being operated with no restrictions due to the special features of their running gear.
Vehicles equipped with variable-gauge running gear shall be able to negotiate curves with a radius of 150 m when coupled into a train.
Individual wagons shall be able to negotiate curves with a radius of 75 m. Wagons intended to be operated between the 1 435 mm and 1 520 mm track gauge systems shall be able to negotiate curves with a radius of 60 m either when empty or loaded.
In order to identify the variable-gauge running gear, rules for marking, as set out in EN 15877-1, shall be applied to all types of vehicles and nominal track gauges.
NOTE The referred standard was originally intended for wagons only.
For the design of the variable-gauge system, the following points shall be considered:
— suitable combinations shall be chosen in order to avoid frictional corrosion on sliding surfaces between axle body and wheel hub. Protection against corrosion and dirt of the locking system and bearing surfaces for axial movement of wheels shall be taken into account;
— vehicles shall be designed to be lifted without dismounting their running gear;
— it should be possible to fit and remove wheelsets with the equipment for lifting and exchange that is normally used for standard wheelsets;
— reprofiling of wheels should not require any equipment other than that for standard wheelsets;
— checks on wheelset geometry shall be possible and integrity should be possible by using existing equipment for measuring and testing.
6.2.2 Axle
Depending on the technology, two main types of axles can be distinguished: rotating axles and nonrotating axles with freely rotating wheels.
Validation of axles shall be documented in a validation plan according to EN 15827:
— Rotating axles:
• methods for calculation as set out in EN 13103-1 shall be applied according to the design of the system. Requirements from EN 13261 shall also be considered;
NOTE In these cases, the validation plan identifies that EN 13103-1 and EN 13261 are fulfilled and no further assessment is necessary.
• when design is out of the scope of EN 13103-1, the calculation should follow as far as possible the methods and load systems provided for in this document. Requirements from EN 13261 shall be considered when applicable.
— Non-rotating axles with freely rotating wheels:
• non-rotating axles with freely rotating wheels are not subject to rotating bending stresses. In addition, the number of cycles and the range of dynamic forces that non-rotating axles shall withstand are much lower. They shall, therefore, be considered as a part of the running gear frame to be calculated and approved according to EN 13749.
6.2.3 Wheel
Wheels shall comply with EN 13979-1 and EN 13262. When these standards do not apply due to the use of other type of technology, they should be considered at least as a guide. A validation process according to 6.3.1 shall be applied in any case.
NOTE When wheels comply with EN 13979-1 and EN 13262, the validation process is defined in EN 13979-1.
Any tread profile may be used, but the dynamic behaviour shall always be in accordance with EN 14363.BS EN 17069-1 pdf download.