The engine cylinder head is installed on top of the engine block, installed on the top of the cylinder block and formed the combustion chamber. The cylinder head is an integral part of the combustion chamber. Its shape of the combustion chamber has a great influence on the operation of the engine. Due to the different combustion methods of gasoline and diesel engines, the parts of the cylinder head that make up the combustion chamber are quite different. The combustion chamber of a gasoline engine is mainly located on the cylinder head, while the combustion chamber of a diesel engine is mainly located in the pit on the top of the piston.
It is often mixed with high temperature and high-pressure gas, so it works with a large thermal load and mechanical load. A cooling water jacket is combined inside the cylinder head of the water-cooled engine, and the cooling water hole on the bottom of the cylinder head is tubed with the cooling water hole of the cylinder block to cool down the combustion chamber with circulating water.
There are also intake and exhaust valve seats, and valve guide holes in the cylinder head. There is a spark plug hole for gasoline engines and a fuel injector hole for diesel engines separately. The cylinder head of the overhead camshaft engine is also machined with a camshaft bearing hole for installing the camshaft.
The cylinder head is generally made of gray cast iron or alloy Aluminum. The aluminum alloy is good to improve the compression ratio. Therefore, in recent years, aluminum alloy cylinder heads have been implemented more and more.