
GL Environment
ⅠIntroduction
The five series of mechanical diaphragm pumps HJ-W、HD、HJ-Z、HJ-D are
reciprocating compound dosing pumps designed and developed by our
company.The transport flow rate of HJ-W pump reaches 30L/H, pressure is 1.0Mpa,
HD and HJ-L pump reaches 150L/H, and the pressure is 1.0Mpa.HJ-Z pump
reaches 500L/h and the pressure is 1.2Mpa. and HJ-D pump transport flow up to
2000L / h, pressure is 1.0Mpa.These five series of pumps feature is mechanically
driven diaphragm.The diaphragm eliminates the structural form of the PTFE thin
membrane combined with the rubber and the iron core, and the corrugation increases
the diaphragm stroke.The stroke adjustment mechanism replaces the effective stroke
adjustment design of the conventional eccentric cam based on the working principle
of the variable eccentric mechanism. This design significantly reduces the pulsation of
pressure and flow, so that the flow rate is in the range of 10 to 100%, and the stability
accuracy can be controlled at ±2%.
ⅡOperating principle of the pump
The pump is composed of two parts: the transmission end part and the hydraulic
end (pump head) part.The output flow of the pump depends on the stroke speed of the
drive end, the diameter of the diaphragm (pump head) and the length of the
diaphragm stroke.When the pump is running or stopped, the stroke length can be
changed by adjusting the stroke adjustment hand wheel. According to the variable
eccentric crankshaft rotation, the adjustable eccentric crankshaft transmits the
reciprocating motion to the diaphragm through the connecting rod, causing the
diaphragm to flex and deformation.The stroke length can be adjusted by changing the
position of the variable eccentric crankshaft on the connecting rod.When the pump is
in the suction stroke, the diaphragm starts to move backwards, and the pressure in the
pump head immediately decreases; when the pump head pressure is lower than the
suction line pressure, the valve ball of the suction port check valve is pushed up
upward,the medium in the inlet line enters the pump head chamber.When the liquid
suction stroke ends, the diaphragm movement stops instantaneously, the pressure in
the pump head is equal to the pressure in the suction line, and the suction port check
valve is reset.
When the pump is in the discharge stroke, the diaphragm begins to move forward
and the pressure in the pump head rises immediately. When the pump head pressure is
higher than the discharge line pressure, the discharge port check valve ball is "pushed
open" upward, and the liquid in the pump head enters the discharge line. When the
discharge port stroke ends, the diaphragm stops moving again. The pressure in the
pump head is the same as the pressure in the discharge line, and the discharge port
check valve is reset and then the next cycle is started. During the suction stroke, the
pressure in the pump head must be higher than the material vapor pressure. If the
liquid pressure is lower than its vaporization pressure, cavitation will occur and affect
the performance of the pump.