Piston Rings
Every piston is fitted with piston rings. The piston rings must seal off the
combustion chamber and the working space from the crankcase and strip
the oil from the cylinder walls, thereby regulating oil consumption. They
must also dissipate the heat absorbed by the piston during combustion to
the cooled barrel. This is one of the most critical component in the
combustion engine as the compression and the forces generated in the
combustion are linked to the performance of the Ring Sealing Efficiency.
There is a continuous development and design up gradation in the
improving efficiency, performance and life of this precision part.
Piston
The piston is a moving part of the combustion chamber. It is responsible for
converting the energy released during the combustion process into
mechanical work. The piston also performs a number of other important
tasks:It seals the combustion chamber, guides the connecting rod,
dissipates the heat generated in the combustion chamber, supports gas
exchange , supports mixture preparation, carries the sealing elements
(piston rings).
The piston is exposed to various forces.
• Piston Force When the engine is running, it moves up and down constantly in the cylinder. At each reversing point it is braked sharply and then accelerated again.This generates mass inertia forces which act on the piston. Together with the forces generated from the gas pressure, they form the piston force. lateral force or normal force : This piston force is transmitted to connecting rod and the crankshaft. However, the connecting rod is only precisely vertical at the upper and lower reversing points (known as dead centre). The inclination of the connecting rod pushes the piston to the side, i.e. against the cylinder wall. The extent of this lateral force changes direction several times during an operating cycle. It is determined by the piston force and the angle of the piston crown in relation to the connecting rod axis. The lateral force can be derived from the parallelogram of forces.
• Piston Force When the engine is running, it moves up and down constantly in the cylinder. At each reversing point it is braked sharply and then accelerated again.This generates mass inertia forces which act on the piston. Together with the forces generated from the gas pressure, they form the piston force. lateral force or normal force : This piston force is transmitted to connecting rod and the crankshaft. However, the connecting rod is only precisely vertical at the upper and lower reversing points (known as dead centre). The inclination of the connecting rod pushes the piston to the side, i.e. against the cylinder wall. The extent of this lateral force changes direction several times during an operating cycle. It is determined by the piston force and the angle of the piston crown in relation to the connecting rod axis. The lateral force can be derived from the parallelogram of forces.
Cylinders Liners
The cylinders of a combustion engine from the working space and
combustion chamber. The cylinders are also charged with the task of
guideline pistons as they move up and down and directing the heat
generated during the combustion process to the cooling system. The
cylinder wall is wetted with oil to ensure sufficient lubrication to pistons and
piston rings moving up and down inside the cylinder.
Appropriate materials are selected to safeguard good heat transfer to the
engine block or coolant. Depending on their design, cylinders can be made
from different alloys of grey cast iron and may be Air Cooled, Air Cooled,
Full or Semi Finish.
Gaskets
Gaskets are highly technical and complex engine components. They are
used in many different forms and material compositions in modern
combustion engines and assemblies (gearboxes, axles, etc.).
The primary task of gaskets gases is to seal off the various media in the
engine (including gases, water and oil) from both one another and the
outside world . However, gaskets also function as power transmission links.
Modern high-performance sealing systems we very reliable. Engine
designers and component manufacturers have spent a great deal of time
and effort developing product solutions. which can be relied upon for sale
operation even under critical boundary conditions. Accordingly, modern
sealing systems are able to withstand aggressive media, high pressures and
equally high temperatures throughout the lifetime of car.
Bearings & Bushes
Function Plain bearings support and guide moving components inside the
engine. Their primary purpose is to facilitate the virtually wear-free rotation
of these components.
Function Plain bearings support and guide moving components inside the
engine. Their primary purpose is to facilitate the virtually wear components.
Plain bearings comprise one or two bearing shells which are locked firmly in
place in the bearing seat. The bearing shells wrap around the rotating shaft
at the bearing journals. Engine oil is pushed into the plain bearing through
a bore hole. During normal operation of the engine, the shaft virtually
guides above the film of oil without touching the bearing shell.
Plain bearings absorb the axial and radial forces, redirecting them to the
bearing housing. Plain bearings are used both for rotating shafts
Connecting Rods
The connecting rod converts the linear up and down movement of the
piston into the circular motion of the crankshaft and is therefore subject to
tension, compression, bending and buckling.
The connecting rod is mounted on the crank pin of the crankshaft with a
plain bearing. The connecting rod bearing cap is bolted to the big end. In
most cases the connecting rod has oil duct in body to supply the gudgeon
pin with lubricant.
To obtain minimal weight and high strength, connecting rods are made
from different materials: Microalloyed steels; Sintered metals, High-grade
aluminium, CFRP and titanium (for high-performance engines)
Forged connecting rods exhibit a better strength-to-weight ratio and lower
costs than sintered connecting rods. Mass-produced connecting rods are
forged, cast or sintered.
