· High performance plunger, special imported packing and sealing components with a long service life and excellent sealing performance; · Inlet and outlet high-precision check valves can effectively guarantee metering accuracy and fluidity; · Generally, the plunger diameter is: D=ф2-ф150mm; · A simple structure, convenient maintenance and high cost effectiveness; · Integrated worm gear, used as a variable speed transmission mechanism, features low noise and high efficiency; · Adoption of a patented integrated sleeve adjustable eccentric transmission mechanism, simple and reliable, and stroke can be steplessly adjusted in the range of 0%-100%, the metering accuracy is ±0.5% (10%-100% adjustment range); · Oil-immersion lubrication ensures reliable use of the transmission mechanism for a long term; · Capacity control modes are diversified, including manual, electrical, pneumatic and frequency conversion adjustment; · An electric actuator is supplied to realize automatic remote control; · Two pump heads or multiple heads (12 at most) can be connected in parallel; a pump with two or more heads can be used to transport a same fluid to reduce pulses or transport different fluids as a proportioning pump; · Due to absence of a safety relief device, it is suggested to install a safety valve on the outlet pipeline of a pump.