German ORSTA pump ORSTA model ORSTA price

ORSTA pumps are rotary pumps that transport liquids or increase their pressure by relying on the change and movement of the working volume formed between the pump cylinder and the meshing gears. Two enclosed spaces are formed by two gears, the pump body, and the front and rear covers. When the gears rotate, the volume of the space on the disengaging side increases from small to large, creating a vacuum that draws in the liquid, while the volume of the space on the meshing side decreases from large to small, squeezing the liquid into the pipeline. The suction chamber and the discharge chamber are separated by the meshing line of the two gears. The pressure at the outlet of a gear pump depends entirely on the magnitude of the resistance at the pump outlet.

ORSTA pump motor features

1) Compact structure, small size, and light weight: Composed of an aluminum alloy front cover, intermediate body, and rear cover, along with components such as alloy steel gears and aluminum alloy pressure plates. Two DU bearings are press-fitted into the front and rear covers respectively. DU material is an ideal bearing material for gear pumps, significantly extending the service life of the gear pump. 2) Reliable operation: The pressure plate is the main component for radial and axial pressure compensation. It reduces bearing load and automatically adjusts the axial clearance of the gear pump, thereby effectively improving the performance indicators and operational reliability of the gear pump. The GM5 and GPC4 series gear motors offer four structural configurations: single rotation direction without front bearing, dual rotation direction without front bearing, single rotation direction with front bearing, and dual rotation direction with front bearing. Gear motors with front bearings can withstand both radial and axial forces. 3) High speed and high pressure: Rotational speed ranges from 3000 to 4000 rpm, with a theoretical torque of 17N.m (N·m) to 64N.m, reaching pressures up to 20-25MPa. 4) Connection methods suitable for imported machinery and engineering equipment: Complies with SAE and national standard GB for mounting flanges, shaft extensions, and inlet/outlet port connections. Widely applicable to hydraulic systems in automobiles, tractors, engineering machinery, agricultural machinery, and other mechanical equipment.

ORSTA pump working principle

The concept of a gear pump is very simple. Its most basic form consists of two gears of identical size meshing and rotating within a closely fitted housing. The interior of this housing resembles a figure-8 shape, with the two gears installed inside. The outer diameter of the gears and their sides fit closely with the housing. Material from the extruder enters the space between the two gears at the suction inlet, filling this space. As the teeth rotate, the material moves along the housing and is finally discharged when the two teeth mesh. Gear pumps are also known as positive displacement devices. Similar to a piston in a cylinder, when one tooth enters the fluid space of another tooth, the liquid and the tooth cannot occupy the same space simultaneously because the liquid is incompressible. Consequently, the liquid is mechanically squeezed out. Due to the continuous meshing of the teeth, this phenomenon occurs continuously, providing a continuous discharge volume at the pump outlet. The discharged volume per revolution is constant. As the drive shaft rotates uninterrupted, the pump discharges fluid without interruption. The pump flow rate is directly related to the pump speed. In practice, there is a small amount of fluid loss within the pump because some fluid is used to lubricate the bearings and the sides of the gears. Furthermore, it is impossible for the pump body to have a gap-free fit, so the fluid cannot be discharged 100% from the outlet. Therefore, a small amount of fluid loss is inevitable, preventing the pump's operating efficiency from reaching 100%. However, the pump can still operate well, achieving efficiencies of 93% to 98% for most extruded materials. This type of pump is not significantly affected by changes in fluid viscosity or density during the process. If a damper, such as a filter screen or restrictor, is placed on the discharge side, the pump will push the fluid through them. If this damper changes during operation—for example, if the filter becomes dirty or clogged, or if the back pressure of the restrictor increases—the pump will maintain a constant flow rate until the mechanical limit of the weakest component in the system is reached (a torque limiter is usually installed). There is actually a limit to the rotational speed of a pump, which mainly depends on the process fluid. If oil is being transported, the pump can rotate at high speeds; however, if the fluid is a high-viscosity polymer melt, this limitation increases significantly. It is crucial to fill the space between the two teeth on the suction inlet side with high-viscosity fluid. If this space is not completely filled, the pump cannot discharge an accurate flow rate. Therefore, the PV value (pressure × flow velocity) is another limiting factor and a process variable. Due to these limitations, gear pump manufacturers offer a range of products with different specifications and displacements (volume discharged per revolution). These pumps are matched to specific application processes to optimize system capacity and price.

ORSTA pump trapped oil phenomenon

For a gear pump to operate smoothly, the contact ratio of the gear meshing must be greater than 1. Consequently, there are always two pairs of gears meshing simultaneously, trapping a portion of the oil in the enclosed cavity formed by these two pairs of gear teeth. This enclosed cavity gradually decreases in volume as the gears rotate, and then gradually increases. The reduction in the enclosed cavity volume compresses the trapped oil, generating high pressure and forcing it out through gaps. This causes the oil to heat up and imposes additional loads on the components. Conversely, an increase in the enclosed cavity volume creates a local vacuum, causing dissolved gases in the oil to separate and resulting in cavitation. These effects produce strong vibration and noise, known as the trapped oil phenomenon in gear pumps. 1) Hazards: Significant radial unbalanced forces can cause shaft bending, contact between the gear tips and the housing, accelerated bearing wear, and reduced bearing life. 2) Elimination method: The usual method to eliminate trapped oil is to machine relief grooves on the side covers. When the enclosed cavity volume decreases, it connects to the pressure oil chamber through the left relief groove; when the volume increases, it connects to the suction oil chamber through the right relief groove.

Weidou Intelligent Technology specializes in selling German ORSTA gear pumps, ORSTA gear pumps, ORSTA diaphragm pumps, ORSTA centrifugal pumps, ORSTA piston pumps, ORSTA vacuum pumps, ORSTA screw pumps, ORSTA submersible pumps, ORSTA peristaltic pumps, ORSTA lubrication pumps, ORSTA vane pumps, ORSTA metering pumps, ORSTA hand pumps, ORSTA drum pumps, ORSTA lobe pumps, ORSTA booster pumps, ORSTA liquid pumps, and ORSTA air pumps. Original imports from Germany. Welcome inquiries and orders from users.