Electricity is one of the biggest cost expenditures for injection
moulding products besides raw materials. For most injection
moulding machines, electric energy is first converted into kinetic
energy through the motor, then into hydraulic energy through the
oil pump, and then drives the various actions of injection moulding
cycle to complete the injection moulding process. As we all know,
the law of conservation of energy does not increase or decrease in
the process of changing energy from one form to another, but in
fact, energy loses in the process of conversion because of the
"useless" output energy, such as heat energy, produced in the
process of conversion. The essence of energy saving is to reduce
the "useless" output energy.
Asynchronous Motor Quantitative Pump
Traditional injection moulding machine uses asynchronous motor
(squirrel cage) to provide power. The constant speed asynchronous
motor converts electric energy into kinetic energy. The output
"useful" kinetic energy is only about 90% of the input electric
energy (when full load), while the others become thermal energy.
Therefore, the motor will bring its own fan to take away the heat
energy.
On the one hand, the induction motor drives the quantitative pump
to output constant flow; on the other hand, the flow requirements
of each action in the injection cycle, such as opening and closing
die, ejection and so on, are different, and the unnecessary flow
will flow back to the tank under the set pressure at that time. The
slower the action is, or the greater the set pressure is, the more
energy will be wasted, and the waste energy will become heat
energy, which will increase the oil temperature. Therefore,
generally speaking, the farther the action speed is from the full
speed, the longer the time is, and the greater the pressure is, the
greater the potential energy-saving range is.
