key superior feature of this rail pad is:-
1. Reduces vibration and impact transmission from rail to
sleeper by providing resilience and impact attenuation.
2. Give adequate resistance to longitudinal and rotational
movement of rail.
3. Ensures long life- Minimum 10 years.
4. Properties are stable over a wide range of operating
temperatures during life.
5. It does not deform, abrade or move out of fastening system
under dynamic loads.
6. It is not adversely affected by ozone, ultra violet light ,
oils and related chemicals.
7. Reduces possibility of rail foot corrosion and concrete
8. Provides more resistance to longitudinal rail movement due
to creep or thermal expansion.
9. Provides electrical résistance between rail
10. Provides conforming layer between rail and sleeper to
avoid contact areas of high pressure.
The design , material of the pad and vulcanizing process need to
be given due consideration so as to obtain the fine balance
between resilience and damping , creep properties and fatigue
life of the rubber. The above mentioned salient advantages are
obtained by adopting a multi pronged approach as briefly given
a) Optimized shape factor: The
ratio of loaded area to the force free area has been optimized
after computer simulations,
b) Right ingredients: natural
rubber RMA 1X which is completely free from dust, particles of
bark of rubber trees etc. is used instead of RMA IV specified in
IR specification along with synthetic rubber.
c) Right Vulcanizing agent. : Our
vulcanizing agent does not leave any free sulphur practically
after vulcanizing, which in other cases continues the
vulcanization process in service and results in premature
d) Anti-degradants: A mix of anti
oxidant, anti ozonants , anti flex resistant chemicals are used.
This is in addition to protective agents against heat.
e) Fillers: Only reinforcing
fillers are used.
f) Coupling Agent:
These chemicals assure a chemical bond between rubber and the
reinforcing filler instead of physical bond.
g) Optimum vulcanizing Process : the rate of heating
and cooling during the process of vulcanization play an
important role in obtaining the final product. These have been
properly designed and followed to obtain the improved rail pad.