RAIL BOND
13,5 mm / M10 stainless steel
SNCF ptnb. 7.952.0882
RAIL BOND
THREAD
M10
DRILLING
DIAMETER :
13,5 mm
THICKNESS
OF RAIL WEB :
17 mm max.
BUSH MATERIAL :
STAINLESS
STEEL


This rail bond is used for connecting electric cables to rails.
It enables to conduct high currents like return of the traction current, as well as low currents like signalling currents.

This rail bond is pre-assembled in factory and consists of :
  • a cylindrical bush 13,5 mm in stainless steel, with a contact flange and tapered bore
  • a stainless steel, tapered dowel with M10 thread
  • a M10 self-locking nut with crimped 27 mm stainless steel washer (*)
  • an anti-friction washer 27 mm (*).
The SNCF rail bond is used with reinforced copper lugs large palm.
(*) Possible with 22 mm when using standard tubular copper lugs.
APPLICATION

* Drilling in the web of the rail :
The hole drilled in the rail web must be 13,5 mm (0/+0,2).
This tolerance is imperative but it is easily achievable using a reamer-drill.

* Setting of the rail bond :
This rail bond is set with a hand hydraulic tool type PH3iN.
It is used to fix the rail bond in the rail by expansion of its bush.
By means of a release valve, adjusted in factory, which limits the hydraulic pressure force, this tool calibrates the force used for setting the rail bond into the rail.

* Connections :
Fit the crimped lug with its cable onto the rail bond.
The anti-friction washer is placed between the nut and the lug (refer to above sketch).
Lug connection is made by tightening the stainless steel nut, which has been given an anti-seizure treatment. A torque wrench is used for this tightening. The torque value to apply is 40 Nm.

* Removing the rail bond :
If the rail bond is damaged by some external force, it may be taken away using a bush remover and a hammer.

TECHNICAL SPECIFICATION

  • Total electrical resistance of the rail bond : 90 µ..
  • Electrical resistance of the contact between the rail bond and the rail : 3 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 before 60 Bar.








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