Screw pump

Screw pump. It is a type of hydraulic pump considered positive displacement, which differs from the usual ones, better known as centrifugal pumps . This pump uses an eccentric helical screw that moves inside a sleeve and fluid flows between the screw and sleeve.


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  • 1 Activity you carry out
  • 2 one-screw pumps (progressive cavity)
    • 1 Double screw pumps
    • 2 Triple screw pumps
  • 3 one-screw pumps (variable capacity)
    • 1 Double screw pumps
    • 2 Triple screw pumps
  • 4 Sources

Activity that performs

It is specifically indicated for pumping viscous fluids, with high solids content, that do not need to be removed or that foam when shaken. As the screw pump displaces the liquid, it does not undergo sudden movements, and can even pump whole grapes. One of the uses it has is to pump sludge from the different stages of the treatment plants, and it can even pump dehydrated sludge from filter press with 22-25% dryness. These types of pumps are widely used in the oil industry worldwide, for pumping highly viscous crudes with appreciable solids contents. New developments of these pumps allow multiphase pumping.

In these types of pumps they can operate with fixed flows at their discharge, even when they pump against a variable pressure network. Converting them into excellent pumping equipment to be used in oil collection networks. In the case of centrifugal pumps. The flow delivered depends on the pressure at its discharge. The liquid is transported by means of an eccentric helical screw that moves inside a sleeve (stator). The insert core of the pump is easy to replace. The driven screws are driven hydraulically.

Screw pump

Single screw pumps (progressive cavity)

The primary components are the rotor and stator. The rotor is a single external propeller and the stator is an internal propeller.

Double screw pumps

These pumps transport their contents axially, uniformly and continuously. During the rotation of the drive screws no turbulence is generated.

Twin screw pump

Triple screw pumps

The triple screw pump generates watertight chambers in the pump core, due to the special profiling of its flanks. Details of running pumps screw pumps a screw with fixed volume capacity:

  1. Connection for accessories.
  2. Stator.
  3. Solid construction bolts.
  4. Two cleaning ports.
  5. Suction housing flange.
  6. Axissolid impeller.
  7. Ball bearings.
  8. Discharge flange.
  9. Rotor.
  10. Suction shell.
  11. Drain plugs.
  12. Connection bar.
  13. Drive shaft.
  14. Shaft seal.

Single screw pumps (variable capacity)

A capacity regulating piston (1) with horizontal movement actuates the sliding valve (2). This modifies the size of the exhaust port (3), thus regulating the transport volume capacity .

  1. Capacity regulating piston.
  2. Sliding valve.
  3. Exhaust hole.
  4. Screw pump outlet.
  5. Screw.
  6. Screw pump inlet.

Double screw pumps

The profile of the screws is such that the drive is completely unloaded, actuated by the driver who carries out the displacement work, acting at the same time as a rotor and displacer. The driven screw performs the mission of separating the intake and discharge cavities, but without dislodging the liquid .

Triple screw pumps

These pumps require the screws to have a cycloidal profile. In a three-screw helical pump, the central one is the conductor and the two lateral ones are the driven ones.


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