. Metering pump is a kind of special volume pump that can meet the needs of various strict technological processes. The flow rate can be adjusted steplessly within the range of 0- 100%, and it is used to transport liquids (especially corrosive liquids).
Metering pump is a kind of fluid conveying machinery, and its outstanding feature is that it can maintain a constant flow regardless of the discharge pressure. The metering pump can complete the functions of conveying, metering and adjusting at the same time, which simplifies the production process. Using multiple metering pumps, several media can be input into the process flow in an accurate proportion for mixing. Because of its own outstanding, metering pump has been widely used in petrochemical, pharmaceutical, food and other industrial fields.
classify
1. According to the overcurrent section
(1) plunger and piston (2) mechanical diaphragm (3) hydraulic diaphragm
2. According to the driving mode
⑵ Motor drive ⑵ Electromagnetic drive.
[14] according to the working mode
(1) Reciprocating type (2) Rotary type (3) Gear type
4, according to the characteristics of the pump
(1) Extra large base (2) Large base (3) Medium base (4) Small base (5) Microcomputer base.
Other classification methods: electric control type, pneumatic control type, thermal insulation type, heating type, high viscosity type, etc.
major feature
Structure of pump
The pump consists of three parts: motor, transmission box and cylinder.
The parts of the transmission box are composed of worm gear mechanism, stroke adjustment mechanism and crank-connecting rod mechanism; The high adjusting stroke is realized by rotating the adjusting handwheel, so as to change the eccentricity of the moving shaft and achieve the purpose of changing the stroke of the plunger (piston).
Cylinder body parts are composed of pump head, suction valve group, discharge valve group, plunger and packing seal.
principle of operation
The motor drives the worm through the coupling and decelerates through the worm wheel, so that the spindle and the eccentric wheel do rotary motion, and the eccentric wheel drives the sliding adjustment seat of the arcuate connecting rod to do reciprocating motion. When the plunger moves to the back dead center, a vacuum gradually forms in the pump cavity, and the suction valve opens to suck in liquid; When the plunger moves to the front dead center, the suction valve is closed and the discharge valve is opened. When the plunger moves further, the liquid is discharged. When the pump works back and forth, it forms a continuous, quantitative and pressurized discharge liquid.
flow control
The flow adjustment of the pump depends on turning the adjusting handwheel to drive the adjusting screw to rotate, so as to change the distance between the arcuate connecting rods and the moving stroke of the plunger (piston) in the pump cavity to determine the flow. Adjusting the handwheel scale determines the plunger stroke, and the accuracy is 95%.
Characteristics of pump
1. The pump has excellent performance, in which the diaphragm metering pump has absolutely no leakage, high safety performance, accurate metering and conveying, adjustable flow from zero to the maximum rating, and optional pressure from normal pressure to the maximum allowable range.
Intuitive adjustment, stable operation, no noise, small size, light weight, convenient maintenance and parallel use.
3. The pump has many varieties and full performance, and is suitable for conveying from -30 degrees to 450 degrees. The viscosity is 0-800mm/s, the maximum discharge pressure is 64Mpa, the flow range is 0.1-20,000 L/h, and the metering accuracy is 1%.
According to the technological requirements, the pump can adjust the flow manually and with frequency conversion, and can also realize remote control and computer automatic control.