Cylinder Head

The cylinder head is fitted above the cylinder block and seals the cylinder from the top and forms the combustion chamber. It is often in contact with high temperature and high pressure gas. Therefore it withstands a lot of heat and mechanical load. There is water channel inside the cylinder head of water-cooled engine. The cooling water hole at the lower end of the cylinder head is communicated with the cooling water hole of the cylinder block. The circulating water is used to cool the high temperature parts such as the combustion chamber.The cylinder head is also equipped with intake and exhaust valve seats, valve guide holes for installing intake and exhaust valves, as well as inlet and exhaust channels. The cylinder head of gasoline engine is processed with a hole for installing spark plug, while the cylinder head of diesel engine is processed with a hole for installing fuel injector. The cylinder head of the overhead camshaft engine is also processed with a camshaft bearing hole for installing the camshaft.Cylinder heads are generally made of gray cast iron or alloy cast iron. Aluminum alloy has good thermal conductivity, which is conducive to improving the compression ratio. So aluminum alloy cylinder head is used more and more.The cylinder head is an integral part of the combustion chamber of which shape has a great influence on the work of the engine. Because of the different combustion modes of gasoline engine and diesel engine, the parts of the cylinder head constituting the combustion chamber are quite different. The combustion chamber of the gasoline engine is mainly in the cylinder head, while the combustion chamber of the diesel engine is mainly in the pit at the top of the piston.