UIC Leaflet 614: Technical Provisions for the End Sections of Tractive Units

What is UIC Leaflet 614?

UIC Leaflet 614 is a vital technical standard titled “Technical provisions relating to the design of the end sections of tractive units.” While UIC 527-2 governs the ends of passenger coaches, UIC 614 focuses specifically on Tractive Units (locomotives, power cars, and shunters).

The end of a locomotive is a complex interface where mechanical, electrical, and pneumatic systems meet. This leaflet ensures that these interfaces are positioned consistently across different manufacturers to allow for Interoperability and to guarantee Operational Safety for the personnel responsible for coupling vehicles.

The “Shunter’s Space” (Berne Rectangle)

A core requirement of UIC 614 is the protection of railway staff. The leaflet defines a specific volume of space at the front and rear of the unit that must remain free of any fixed obstructions.

• Berne Rectangle: A safety zone (typically 400mm wide and 2000mm high) located on either side of the Draw Gear. This allows a shunter to stand safely between the vehicles even when the Buffers are fully compressed.
• Handrails and Footsteps: The leaflet mandates the placement of ergonomic handrails and non-slip footsteps to ensure staff can safely climb onto the Underframe to connect brake hoses or electrical cables.

Geometric Standards for Coupling Equipment

To ensure that a locomotive from one country can successfully couple to a wagon from another, UIC 614 dictates strict tolerances for the following:

• Buffer Height and Spacing: Buffers must be placed at a standard height (940 mm to 1065 mm above rail level) to prevent “telescoping” or overriding during a collision.
• Hook and Screw Coupler: The center of the draw hook must align perfectly with the longitudinal axis of the Rolling Stock.
• Coupling Clearance: Ensuring that the locomotive’s snow plow or aerodynamic fairing does not interfere with the movement of the Screw Coupler in tight curves.

Pneumatic and Electrical Interfaces

Locomotives must provide “services” to the hauled train. UIC 614 standardizes the “cock” positions for:

• Brake Pipes: The Main Brake Pipe (5 bar) and the Main Reservoir Pipe (10 bar).
• UIC 558 Connectors: The 18-core sockets used for remote control and passenger information systems.
• Train Heating: The high-voltage connection points for electrical heating and air conditioning in passenger consists.

Comparison: UIC 614 (Locomotives) vs. UIC 527-2 (Coaches)