Marine diesel engine accessories introduction to cylinder start status

Special measures to prevent serious cylinder damage. In the diesel fuel oil shutdown state, the high pressure oil pump of the diesel engine has fuel, cycle and ring, but the injector and high pressure oil pipe can not achieve, cycle and ring. The temperature of the fuel oil retained inside is only tens of degrees, which is completely unable to reach the viscosity of fuel oil spray atomization. When starting, these oils should all be injected into the cylinder, and the hot oil behind has a heat transfer and cooling problem in the early stage of the high-pressure tubing and injector, which will lead to a very poor state at the time of starting.

Such a state of DK28 diesel engine parts is not very important for the diesel engine with large cylinder diameter, but for the machine with 160mm cylinder diameter, due to the low temperature and pressure at the compression end point, the thermal state of the cylinder at the initial start is very poor, resulting in the fuel injected into the cylinder that cannot be atomized normally being heated and coking. When the exhaust will stick on the open exhaust valve stem, resulting in the air valve is not tightly closed, and the gas valve burns and leaks after normal ignition; The extreme and limited situation will cause the valve to collide with the piston, or the valve will be out of sync with the ejector rod, resulting in the valve bridge slipping out of the original positioning, the valve bridge will be pushed to the spring seat, resulting in flying out, and the valve will eventually fall into the cylinder; This will also lead to a serious deviation in the force of the positioning rod of the valve bridge, resulting in bending and breaking of the positioning rod; Cause serious damage.

The pole and end of the cylinder that are seriously damaged are due to the poor thermal state of the cylinder and poor combustion, which basically does not happen when the load is large. That is to say, under normal working conditions, the thermal state of the cylinder is good, and the combustion is good, such problems will not occur. In addition, this operation also reduces the pollution of the supercharger nozzle ring and turbine blades.