what is an engine cylinder head ?
The top of the cylinder is covered with a separate cut piece called the cylinder head.
The Cylinder Head is bolted to the top of the Cylinder Block. It contains the combustion chamber. It consists of a Spark Plug and some Timing Valves (in I and F-head). This includes routes for the flow of coolant.
The cylinder head is usually made of gray iron or aluminum alloy. Aluminum has the advantages of lightweight and high thermal conductivity. It is inserted separately from the cylinder block so that it can be removed to clean the carbon and grinding valves.
To maintain compression in the cylinder, a flat piece of gasket is placed between the cylinder head and the cylinder block. In some cases such as in racing car engines, a separate head is not used. But making a piece of cylinder block and head is difficult and expensive and the internal parts of the engine are not as accessible. Therefore, it is made separately for the cylinder head and cylinder block so that if there is any defect, it can be easily removed.
Depending on the valve layout, the cylinder may carry a head, camshafts, rockers, and valves. Cooling ports are provided adjacent to the valve and plug seating.
From a mechanical point of view, the design detail of a detachable cylinder head is perhaps the trickiest. The following points should be noted when the data table head is created:
in the cylinder head head machining
The bore of the cylinder or liner should not be deformed by pulling the hold-down stud
The circulation of coolant in the cylinder head should be taken to the upper end as much as possible.
Advantages of aluminum alloy cylinder and head
- higher heat conductivity which is almost three times that of cost iron.
- light in weight
- Increased compression ratio without explosion due to heat conductivity.
- Improved cooling while Enfine is running.
- Higher power output and lower fuel consumption due to increased compression ratio and better cooling effect
- The engine heats up more quickly and requires a smaller radiator.
Disadvantages:-
- Engine costs more due to expensive aluminum
- This low modulus of elasticity is responsible for pushing the studs out of shape.
- Due to the high thermal expansion, greater clearance is required between the piston and the cylinder.
- Cold water more likely to rust
- Sometimes it is necessary to use cast iron valve seating and spark plug inserts
- Due to the inter-metallic corrosion between the steel stud and the aluminum alloy metal, the head may stick to the cylinder block.