German PEDRO ROQUET pump PEDRO ROQUET model PEDRO ROQUET price

PEDRO ROQUET 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 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 to draw 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 discharge chamber are separated by the meshing line of the two gears. The pressure at the discharge port of the gear pump depends entirely on the magnitude of the resistance at the pump outlet.

PEDRO ROQUET pump structural features

1) Simple structure and low cost; 2) Low operational requirements and wide application; 3) The end covers and the spaces between the gear teeth form many fixed sealed working chambers, so it can only be used as a positive displacement pump. The gears adopt the double circular-arc sine curve tooth profile, an advanced technology from the nineteen-nineties. Compared with involute gears, its most prominent advantage is that there is no relative sliding on the tooth flank during meshing, resulting in no wear on the tooth surface, smooth operation, no fluid trapping, low noise, long service life, and high efficiency. This pump breaks away from the constraints of traditional design, bringing gear pump design, production, and use into a new field. The pump is equipped with a differential pressure safety valve for overload protection. The full return pressure of the safety valve is 1.5 times the rated discharge pressure of the pump. It can also be adjusted according to actual needs within the allowable discharge pressure range. However, this safety valve cannot be used as a pressure reducing valve for long-term operation; a pressure reducing valve can be installed separately if needed. The shaft end seal of the pump is designed in two forms: one is mechanical seal, and the other is packing seal, which can be determined according to specific usage conditions and user requirements.

PEDRO ROQUET pump working principle

The concept of a gear pump is very simple. Its most basic form consists of two gears of the same size meshing and rotating against each other within a closely fitted housing. The interior of this housing resembles a "8" shape, with two gears installed inside. The outer diameter of the gears and both sides fit closely with the housing. Material from the extruder enters between the two gears at the suction inlet and fills 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 called positive displacement devices. Like a piston in a cylinder, when one tooth enters the fluid space of another tooth, because the liquid is incompressible, the liquid and the tooth cannot occupy the same space at the same time, so the liquid is mechanically squeezed out. Due to the continuous meshing of the teeth, this phenomenon occurs continuously, thus providing a continuous discharge volume at the pump outlet. The discharged volume is the same for each revolution of the pump. As the drive shaft rotates uninterrupted, the pump discharges fluid uninterrupted. The flow rate of the pump is directly related to the pump speed. In reality, there is a very small amount of fluid loss within the pump, because this fluid is used to lubricate the bearings and both sides of the gears, and the pump body can never fit without gaps, so it is impossible for the fluid to be discharged from the outlet 100%. Therefore, a small amount of fluid loss is inevitable, which prevents the pump's operating efficiency from reaching 100%. However, the pump can still operate well, and for most extruded materials, an efficiency of 93% to 98% can still be achieved. This pump is not significantly affected by fluids whose viscosity or density changes during the process. If there is a damper, such as a filter screen or a restrictor placed on the discharge side, the pump will push the fluid through them. If this damper changes during operation, i.e., if the filter screen becomes dirty or clogged, or if the back pressure of the restrictor increases, the pump will still maintain a constant flow rate until the mechanical limit of the weakest component in the device is reached (usually a torque limiter is 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 a high speed, but when the fluid is a high-viscosity polymer melt, this limit increases significantly. It is very important to fill the space between the two teeth on the suction inlet side with high-viscosity fluid. If this space is not fully 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 will provide a series of products, i.e., different specifications and displacements (the amount discharged per revolution). These pumps will be matched with specific application processes to optimize system capacity and price.

PEDRO ROQUET pump troubleshooting

1) Fault phenomenon: Pump fails to discharge material. Fault causes: a, reverse rotation direction; b, suction or discharge valve closed; c, no material at inlet or pressure too low; d, viscosity too high, pump cannot bite material. Countermeasures: a, confirm rotation direction; b, confirm whether valves are closed; c, check valves and pressure gauge; d, check liquid viscosity to see if flow appears proportional to speed when running at low speed; if there is flow, then inflow is insufficient. 2) Fault phenomenon: Insufficient pump flow. Fault causes: a, suction or discharge valve closed; b, low inlet pressure; c, blocked outlet pipeline; d, packing box leakage; e, speed too low. Countermeasures: a, confirm whether valves are closed; b, check whether valves are open; c, confirm whether discharge volume is normal; d, tighten; if massive leakage affects production, stop operation and dismantle for inspection; e, check actual pump shaft speed. 3) Fault phenomenon: Abnormal noise. Fault causes: a, large eccentricity of coupling or poor lubrication; b, motor failure; c, gearbox abnormality; d, poor installation at shaft seal; e, shaft deformation or wear. Countermeasures: a, align or fill with grease; b, check motor; c, check bearings and gears; d, check shaft seal; e, stop and dismantle for inspection. 4) Fault phenomenon: Excessive current. Fault causes: a, excessive outlet pressure; b, melt viscosity too high; c, poor assembly of shaft seal; d, shaft or bearing wear; e, motor failure. Countermeasures: a, check downstream equipment and pipelines; b, test viscosity; c, check shaft seal and adjust appropriately; d, check after stopping, manually turn to see if it is too heavy; e, check motor. 5) Fault phenomenon: Pump stops suddenly. Fault causes: a, power outage; b, motor overload protection; c, coupling damage; d, excessive outlet pressure, interlock reaction; e, abnormal biting inside pump; f, shaft and bearing adhesion/seizure. Countermeasures: a, check power supply; b, check motor; c, open safety cover and check by manual turning; d, check instrument interlock system; e, after stopping, confirm by manual turning in forward and reverse directions; f, confirm by manual turning. 6) Fault phenomenon: Seal oil leakage. Causes: a, shaft seal not adjusted properly; b, sealing ring worn resulting in large gap; c, dynamic and static ring friction surfaces of mechanical seal damaged; d, spring relaxation. Countermeasures: a, readjust; b, tighten gland bolts appropriately or replace sealing ring; c, replace dynamic and static rings or regrind; d, replace spring.

Weidou Intelligent Technology specializes in selling German PEDRO ROQUET gear pumps, PEDRO ROQUET gear pumps, PEDRO ROQUET diaphragm pumps, PEDRO ROQUET centrifugal pumps, PEDRO ROQUET piston pumps, PEDRO ROQUET vacuum pumps, PEDRO ROQUET screw pumps, PEDRO ROQUET submersible pumps, PEDRO ROQUET peristaltic pumps, PEDRO ROQUET lubrication pumps, PEDRO ROQUET vane pumps, PEDRO ROQUET metering pumps, PEDRO ROQUET hand pumps, PEDRO ROQUET drum pumps, PEDRO ROQUET lobe pumps, PEDRO ROQUET booster pumps, PEDRO ROQUET liquid pumps, PEDRO ROQUET air pumps. Original imports from Germany. Welcome customers to inquire and order.