SHORT RAIL BOND
13,5 mm / M10 copper bush
SNCF ptnb. 7.952.0900
RAIL BOND
THREAD
M10
DRILLING
DIAMETER :
13,5 mm
THICKNESS
OF RAIL WEB :
mini. 15 mm
BUSH MATERIAL
TIN-PLATED
COPPER

With the same objective of achieving connection reliability, the short rail bond has been developed on request of the French National Railways Company, S.N.C.F.
This rail bond operates on the same way as the standard rail bond, with SNCF ptnb. 7.952.0882 since 1993, and hydraulic setting tool is the same (PH3iN).


The connection is doubled by two short rail bonds fitted in a same hole on both sides of the rail.
The detection of broken rail is also preserved. Rails bonds are completely independent from one to each other, which enables intervention on one of the cables while maintening, in most cases, installation's availability.
Why having developed short rail bond, for two main applications :

1- Redundancy effect :
  • This type of rail bond improves availability of installations for track-circuit and return traction currents.
  • The detection of broken rail is preserved.
  • The redundancy is secured with twin rail bonds completely independent from one to each other.
  • Short rail bonds can be set where and instead of a connection made with a standard rail bond.
2- Mono-connection :
  • The number of rail drillings is reduced.
  • The implementation of the polarity transfer is easier.
  • The detection of broken rail is clearly improved of :
    • 100% if 2 cables,
    • 50 % if 3 cables.

TECHNICAL SPECIFICATION

  • Total electrical resistance of the short rail bond : 12 µ..
  • Electrical resistance of the contact between the rail bond and the rail : 6 µ..
  • Ability to withstand short-circuits : the rail bond has been subjected to 3 short-circuit tests at 7000 A. 0,2 s.
  • Ability to withstand thermal shocks : -30°C to +70°C.
  • Ability to withstand corrosion : tested for 300 hours in salt mist according to standard NFX41002.
  • Ability to withstand vibration : acceleration from 7 g to 16 g along 3 axes, 8 hours per axis.
  • Ability to withstand heating : heating cycle to simulate the passage of trains
    (current between 1000 and 1500 A) for 50 mn (simulation of passage of 10 trains).
  • Ability to withstand pressure (coloured water at pressure) : no leakage at 250 Bar.


Rail bonds delivered
in storage box
(10 rail bonds per box).