The heavy cylinder constant innovation in the social practice

Heavy cylinder is the main part of the engine, it will become an organic whole repeatedly each cylinder and crankcase, is to install piston, crankshaft and other parts and accessories bearing skeleton. Basic on modern cars are using water-cooled multi-cylinder engine, for multi-cylinder engine, cylinder arrangement determines the engine installation dimensions and structure characteristics of the engine also has effect on the stiffness and strength of the body, and relates to the overall layout of car. Market research shows that water cooling engine cylinder block and the upper crankcase often cast, known as the cylinder block - — Crankcase, may also be referred to as the cylinder block. General use grey cast iron cylinder block, cylinder block upper cylindrical cavity called the cylinder, the lower part for supporting the crankcase, crankshaft inside cavity space of the movement of the crankshaft. There are many reinforcement inside the cylinder block casting, cooling water jacket and oil duct, etc. Heavy cylinder should have sufficient strength and stiffness, according to the cylinder block and oil pan in the plane of the installation position is different, usually the cylinder block is divided into the following three forms. ( ) General type cylinder block is characterized by installing plane and crankshaft oil pan center at the same level. The advantage of the cylinder block is the body height is small, light weight, compact structure, easy processing, crankshaft tear open outfit is convenient; But its drawback is that poor stiffness and strength, ) Gantry cylinder block is characterized by the oil pan installed plane is lower than the rotation of the crank shaft center. It has the advantage of the strength and stiffness are good, can bear larger mechanical load; But the downside is poor manufacturability, heavy structure, processing more difficult. ( ) Tunnel type cylinder block this kind of crankshaft main bearing hole of the cylinder block as the integral, using rolling bearing, main bearing hole is bigger, the crankshaft from the cylinder block at the back of the load. Its advantage is compact structure, good rigidity and intensity, but its drawback is that require high machining accuracy, poor manufacturability, crankshaft, dismantling inconvenient. The working conditions of heavy cylinder is very bad. It to burn in the process of rapid change of pressure and temperature and intense friction of piston movement. Therefore, it should have the following properties: (1) there is enough strength and stiffness, small deformation, ensure correct location of the movement parts, operating normally, vibration noise is small. (2) has the good cooling performance, the cooling water jacket around the perimeter of the cylinder, so that the cooling water heat can be taken away. (3) wear-resisting, in order to assure the service life of cylinder block has enough. The upper cylinder block is tied for the cylinder tube, now with a jacket. The bottom of the cylinder block is the crankcase, crankshaft, used to install the outside also can be installed the generator, engine mounts and other accessories. Most of cylinder block cast iron or cast aluminum alloy, aluminum alloy cylinder cost is higher, but light weight, good cooling performance, get more and more widely used. Is body is constitute the skeleton of engine, engine agencies and the installation of each system, installed inside and outside the engine parts and accessories, all the major under various loads. Therefore, the body must have enough strength and stiffness. The body group is mainly composed of cylinder block, crankcase, cylinder head and cylinder pad and other parts.