Basic concept of precision gear pump.

precision gear pump is a rotary pump that relies on the change and movement of the working volume formed between the pump cylinder and the meshing gears to convey liquid or to pressurize it. When the gears rotate, the volume of the space on the disengaged side of the gears changes from small to large to form a vacuum, and the volume of the space on the engaged side of the gears changes from large to small to squeeze the liquid into the pipeline. The suction chamber and the discharge chamber are separated by the meshing line of two gears. The pressure at the discharge of the gear pump depends entirely on the size of the resistance at the pump outlet.

Drive unit.

The precision gear pump is driven by an independent motor, which effectively blocks upstream pressure pulsations and flow fluctuations. The pressure pulsation at the outlet of the gear pump can be controlled to within 1%. The use of a gear pump in the extrusion line can increase the flow output speed and reduce the shearing and residence time of the material in the extruder.

When the precision gear pump works, the main wheel rotates with the motor and drives the driven wheel to follow the rotation. When the meshed teeth on the side of the suction chamber gradually separate, the volume of the suction chamber increases and the pressure decreases, the liquid in the suction tube is sucked into the pump; the suction liquid is pushed to the discharge chamber by the gear in two ways in the gear groove. After the liquid enters the discharge chamber, as the teeth of the two gears keep meshing, the liquid is squeezed and enters the discharge pipe from the discharge chamber. The main gear and the driven gear keep rotating, and the pump can continuously suck in and discharge the liquid.

Structural features of precision gear pump

(1) Simple structure and low price.

(2) Low working requirement and wide application.

(3) The end cover and the various interdental grooves of the gears form a number of fixed sealed working chambers, which can only be used as a quantitative pump.

Classification of precision gear pump.

External gear pump: the most widely used kind of gear pump, general gear pump usually refers to the external gear pump. There are mainly active gears, driven gears, pump body, pump cover and safety valve. Pump body, pump cover and gears constitute the sealing space is the gear pump studio. The shafts of the two gears are installed in the bearing holes on the two pump covers, and the active gear shaft extends out of the pump body and is driven by the motor to rotate. External gear pump is simple in structure, light in weight, low in cost, reliable in work and wide in application.

Internal gear pump: It consists of a pair of internal gears meshing with each other, the crescent-shaped part in between them and the pump casing. The role of the crescent-shaped piece is to separate the suction chamber and the discharge chamber. When the active gear rotates, a local vacuum is formed at the place where the gears are disengaged, and the liquid is sucked into the pump to fill the inhalation chamber between the teeth, and then enters the discharge chamber in two ways along the inner and outer sides of the crescent-shaped parts. At the place where the gears enter into engagement, the liquid existing between the teeth is squeezed and sent into the discharge pipe.

As far as the core component gears are concerned, the main components are the common law gear pump and the circular arc gear pump. Public law line gear pump conveying impurities in the media than the circular arc gear pump is more durable, while the circular arc gear pump structure is special, conveying clean media, low noise, long life, each has its own advantages.

The working characteristics of precision gear pump.

Advantages: simple and compact structure, small volume, light weight, good workmanship, cheap, strong self-priming force, insensitive to oil pollution, large speed range, resistant to shock load, easy maintenance, reliable work.

Disadvantages: unbalanced radial force, large flow pulsation, high noise, low efficiency, poor interchangeability of parts, not easy to repair after wear, can not be used as a variable pump.