rod is a vital component of any internal combustion engine. This is the
component which carries the power from the piston to the crank-shaft
and thus giving movement to the engine.
The basic principle
of connecting rod assembly is the same for all engines except for
the fact that in two-wheelers, at one end, crank pin is used which is
connected to the crank-shaft.
The connecting rod is attached to
the crank-shaft by crank pin and the other end of the connecting rod is
connected to the piston with the piston pin. The connecting rod takes
the power thrust from the reciprocating piston and carries it to the
crank pin which in turn transmits the power / motion to the crank-shaft
in the form of rotary motion which makes the vehicle move. It is utmost
important that the connecting rod should be of correct weight and size
so that there is no vibration in the connecting rod while transmission
of power. Also the dimensional parameters and the heat treatment
parameters should be strictly maintained to ensure trouble free running
of the engine.
Pin is a high precision item, having
round cylindrical shape. It can be
of hole or solid type, but must have a high surface finish, to serve as
running surface for needle bearings. The surface must be free from nick
marks and must be hard, to bear the normal wear and tear of the
vehicle. It is firmly connected to the connecting rod and as such the
geometry of the outer diameter as well as side faces plays a vital role
in fitment and running. It is a vital part of kinematics of the
transmission of a two / three wheeler assembly, where a direct transfer
of power, without slip, is sought from the Piston to the wheel / gear
box. A similar situation prevails in single cylinder engines for
agriculture, industrial and other uses.
and mostly in American nomenclature known as wrist pins, are an
integral part of all types of internal combustion engines, Otto or
diesel types, 2 strokes and 4 types. Gudgeon pin is a component to
fasten the piston and the connecting rod severally and securely, but at
the same time permitting enough play for the free angular movement of
the connecting rod according to the requirements of kinematics of the
They are very essential for the carefree running
of the engine and it depends upon the quality of the gudgeon pin
whether an engine will live upto its designed life period of operation.
The power generated by the combustion of inflamed gases is harnessed by
the piston and transmitted further to the crank shaft via piston rod, in
which the gudgeon pin plays a vital pivotal role.
Most of the
gudgeon pins are hollow cylinders made out of special alloy steels
having highly polished and hard outer surface to bear the wear and tear
due to the to and fro motion of the piston shaft.
are used in scooters, motorcycles, mopeds, cars, lorries, trucks,
locomotives, tractors, marine engines, refrigeration compressors etc.