The plunger metering pump includes both a valve pump and a valveless pump. The plunger metering pump is widely used in the field of petrochemical industry because of its simple structure and high temperature and high pressure. Plunger material is stainless steel, oxidized ceramic, ceramic oxide with high corrosion resistance and high wear resistance characteristics. In view of the shortcomings of ordinary piston pump under high pressure condition, Plunger-type Metering Pump a kind of valveless rotary plunger metering pump is paid more and more attention. It is widely used in high viscosity medium such as syrup, chocolate and petroleum additive. Metering addition.
Principle of plunger metering pump
The plunger metering pump draws and discharges the working medium (yellow) directly through the reciprocating motion of the plunger. Since the plunger and the seal are in contact with the media, the choice of the appropriate plunger material and sealing form to ensure that the pump in the process of running with the desired performance.
Piston metering pump is a reciprocating pump, belonging to the volume pump, Plunger-type Metering Pump the plunger by the axial rotation of the shaft drive, reciprocating motion, the suction and discharge valves are one-way valve. When the plunger is pulled, the pressure in the working chamber is reduced, the outlet valve is closed, Plunger-type Metering Pump below the inlet pressure, the inlet valve opens, the liquid enters; when the plunger is pushed, the working chamber pressure rises, the inlet valve closes, The outlet valve is open and the liquid is discharged. When the drive shaft drives the cylinder to rotate, Plunger-type Metering Pump the swash plate pulls the plunger out of the cylinder or pushes it back to complete the suction and discharge process. Plunger and cylinder bore working chamber composed of oil through the oil pan, respectively, and pump suction and discharge chamber connected. Plunger-type Metering Pump The variable mechanism is used to change the inclination of the swash plate, and the displacement of the pump can be changed by adjusting the inclination of the swash plate.
The plunger metering pump is used to accurately and quantitatively deliver liquid without solid particles to pressurized or atmospheric vessels and pipes. Plunger-type Metering Pump Different types of plunger metering pumps can be assembled according to the requirements of variable frequency motor (to receive 4-20mA current signal) or explosion-proof motor. Plunger pump head structure is simple, economical, high precision measurement, the need to select and maintain a good seal. The vertical alignment between the plunger and the seal ensures a small wear between the two.
1, into the oil process
When the cam part of the convex part of the turn, under the action of the spring force, the plunger down movement, the plunger upper space (called the pump room) to produce a vacuum, Plunger-type Metering Pump when the plunger on the end of the plunger After the oil hole is opened, the diesel oil is filled with oil in the oil passage of the oil pump, and the plunger moves to the bottom dead center and the oil is finished.
2, the oil supply process
When the camshaft to the cam part of the raised part of the roller body, the plunger spring is compressed, the plunger upward movement, fuel pressure, a part of the fuel flow through the oil hole pump oil chamber. When the top surface of the plunger covers the upper edge of the oil inlet of the sleeve, Plunger-type Metering Pump the plunger and the sleeve have a small clearance (0.0015-0.0025 mm) so that the pump chamber at the top of the plunger becomes a sealed oil chamber, Continue to rise, the pump oil quickly increase the oil pressure, Plunger-type Metering Pump the pump pressure> oil valve spring force + high pressure tubing residual pressure, push out the oil valve, high pressure diesel oil through the oil valve into the high pressure tubing, through the injector spray Into the combustion chamber.
3, oil return process
The plunger is supplied with oil, and when the chute (stop) on the plunger is connected to the oil return hole on the sleeve, the low pressure oil passage of the pump chamber is connected with the middle and radial holes of the plunger head And chute communication, plunger metering pump hydraulic pressure suddenly dropped, Plunger-type Metering Pump the valve under the action of the spring force quickly shut down to stop the oil supply. After the plunger also up, when the cam part of the convex part of the turn, under the action of the spring, the plunger and down. The next cycle starts.
