Skills for Use of Construction Dump Trucks in Alpine Plateau Area I

1. Reducing oil supply of the dump truck radiator

Because the oxygen content in the tunnel is only about 70% of that in the plain area, the amount of oxygen entering the cylinder of diesel engine is insufficient, the fuel combustion is incomplete, the consumption is increased, and the exhaust pipe emits black smoke seriously. The main performance parameters of diesel engine vary with altitude as shown in the attached table.

In order to solve the above problems, the high-pressure fuel pump and governor of diesel engine were removed as a whole and installed on a multi-functional and omnidirectional fuel injection pump test bench. The fuel supply was adjusted to 1/10 less than the normal value in plain area. After adjusting the fuel supply, the fuel supply of high-pressure oil pump will be reduced correspondingly at any position of the throttle tie rod, so that the atomized fuel in the cylinder can be fully burned, thus reducing the black smoke emission and fuel consumption.

2. Adding auxiliary starting device of the dump truck radiator

Due to the influence of cold climate in plateau, it is very difficult to start a diesel engine. For this reason, under the condition that the number of teeth, modulus and meshing angle of the driving gear of the starter are the same, the starter with higher power is selected, and the storage battery with large capacity and maintenance-free is preferred. In this way, when starting the diesel engine, the flywheel speed is fast, the duration is long, and the diesel engine is easy to start.

In addition, in order to start the diesel engine smoothly, two sets of auxiliary start-up devices and intake preheating device and fuel heater can be added to the diesel engine. Intake preheating device can still be used when air temperature reaches - 25 C. It consists of preheating plug, solenoid valve, oil intake pipe, electronic controller, temperature sensor, indicator lamp and other components.

The working principle of the fuel heater is as follows: the battery supplies power to the fuel heater motor (DC24V, 110W), and the motor drives the fuel pump, combustion fan and atomizer to rotate. The fuel inhaled by the fuel pump is sent to the atomizer through the pipeline. After mixing the atomized fuel with the air inhaled by the combustion fan in the main combustion chamber, the fuel is ignited by a hot electric plug and fully combusts in the rear combustion chamber. The heat of combustion is transmitted to the cooling medium in the interlayer of the water jacket through the radiator on the inner wall of the water jacket. Under the action of the pump and the heat convection, the purpose of heating the cylinder block of the diesel engine is achieved.