We produce cast iron railway brake block and composite railway
Cast iron brake block:
There’re two types of cast iron brake block, normal type and high
phosphorous cast iron brake shoe. The difference lies in the
content of the phosphorus. The P content in normal type is
0.7-1.0%, while in high phosphorous cast iron brake block, the P
content is above 10%.
The wear resistance of high phosphorus cast iron brake is 1 times
bigger than normal type. Practice shows that the life span of
high-phosphorus brake block is 2.5 times of the normal type.
High phosphorus brake block is also characterized by little spark.
The friction coefficient increases with the increasing of
phosphorus content, so the friction coefficient of high phosphorus
brake brake is greater than the normal type.
However, the high phosphorus content will increase the brittleness,
so when the phosphorus content is above 1%, there may be crack, so
it requires a backing plate for high phosphorous brake block.
Cast iron brake block has been in use on railway vehicles for more
than a century in history. The main advantages of cast iron brake
1. a small friction coefficient affected by the environment and
more stable, so it is "all-weather" operational;
2. good thermal conductivity, low thermal damage to the wheels;
3. The coarsening of the wheel surface can obtain more adhesion,
which can reduce the mechanical abrasion of the wheel;
4. Durable, low prices.
But the friction coefficient of ordinary gray cast iron brake shoe
is small, and with the increase of friction velocity, friction
coefficient decreased rapidly especially when it is in high-speed
So ordinary cast iron brake shoes are generally used for low-speed
operation of passenger trains.
For cast iron brake used in high speed train, we can improve the
performance by increase the content of phosphorus or add some alloy
In fact, it is the high phosphorus cast iron brake block that is
widely used now, to avoid the crack, a backing plate is used to
Composite brake block:
The composite brake block is more widely used currently.
It is the following advantages:
1. Friction property can be adjust according to requirement.
2. Good wear resistance and long life span.
3. Saving of the cast iron material
4. Small wear to the wheel which can prolong the lifespan of the
5. Light weight, normally it is only 1/2-1/3 of the cast iron brake
6. To avoid iron stain and abrasion due to brake injection spark
caused fires, and to mitigate the adverse effects on electrical
7. The friction coefficient is relatively stable and can ensure
sufficient braking force.
8. Due to the friction coefficient can be sufficiently improved,
the use of composite brake block and small diameter brake cylinder
can save compressed air, thus can shorten refillable time when it
needs continuous braking in high slope areas, so that the security
of running in ramp area is improved.
The materials of composite brake block is asbestos free, it
contains resins, elastomers, friction modifiers and mineral fibers
reinforcing its structure. It contains no lead, zinc or any other
toxic materials, it is environmental friendly, and causes no bad
smell in friction.
The wear of the composite material is very low. The advantage of
this material is a stable coefficient of friction in variable
atmospheric conditions and high thermal resistance.
The composite brake block is particularly beneficial in those
situations where cast iron brake block would cause a safety hazard.
Spark free brake blocks are essential in oil refineries, chemical
works and ordinance factories. The composite brake block has much
to offer in the braking of passenger rail, minimizing braking
shocks by its smooth action and permitting higher load factor.