Marine diesel engine accessories introduction Engine cylinder head
The engine cylinder head is one of the most critical parts in the engine, its precision requirements are high, the processing process is complex, the quality of the processing directly affects the overall performance and quality of the engine, therefore, the processing of the engine cylinder head is particularly important.
The cylinder head is mounted on top of the cylinder block, sealing the cylinder from the top and forming the combustion chamber. It is often in contact with high temperature and high pressure gas, so it bears a large thermal load and mechanical load. A cooling water jacket is made inside the cylinder head of the water-cooled engine, and the cooling water hole at the lower end of the cylinder head is communicated with the cooling water hole of the cylinder body. Circulating water is used to cool high-temperature parts such as the combustion chamber.
The cylinder head is also equipped with inlet and exhaust valve seats, valve guide holes for installing inlet and exhaust valves, as well as intake channels and exhaust channels. The cylinder head of a gasoline engine is machined with a hole for installing the spark plug, while the cylinder head of a diesel engine is machined with a hole for installing the fuel injector. The cylinder head of the overhead camshaft engine is also machined with a camshaft bearing hole for mounting the camshaft.
The cylinder head is generally cast with gray cast iron or alloy cast iron, and the thermal conductivity of aluminum alloy is good, which is conducive to improving the compression ratio.
The cylinder head is a component of the combustion chamber, the shape of the combustion chamber has a great impact on the work of the engine, because of the different combustion methods of gasoline engines and diesel engines, the parts of the combustion chamber on the cylinder head are different. The combustion chamber of gasoline engines is mainly on the cylinder head, while the combustion chamber of diesel engines is mainly in the pit on the top of the piston.