Progressing Cavity Pumps


PROGRESSIVE CAVITY PUMPS, CHARACTERISTICS

Nova Rotors specialises in the construction of progressive cavity pumps. This type of pump is highly flexible in terms of operation and application, a factor which has enabled it to achieve considerable market success. Its unique features makes it suitable for use in a variety of different industries.
The main features of this type of pump are:

Uniform flow proportional to the speed.

  • Self-priming with a maximum suction lift capacity up to 8 mWC (low NPSHa application), depending on the size, the number of stages and pump speed.
  • Capacity to pump heterogeneous products, containing gases, solid, abrasive and fibrous materials in the liquid matrix.
  • Pumping of liquids with low or high viscosity.
  • Liquid dosing capability.
  • Low pulsation pumping with minimum tensile strain of the product being processed.
  • High pumping pressure (6 bar per stage). Pumps are available with one to eight stages, depending on the required pressure.

The progressive cavity pump is a volumetric, self-priming, rotary positive displacement device. The “conveying” parts consists of two elements, the rotor and the stator. The rotor, typically metallic, is single or multiple screw with a rounded thread, extremely large pitch, considerable length and high eccentricity in relation to the core diameter.
The stator, typically elastomeric, is embedded with a cavity in the shape of a 2 or multiple screws, double threaded, compared to the rotor, and with the same eccentricity.
The rotor, rotating within the stator, is forced to perform a hypocycloid roto-translational movement. This coupling of the two elements always creates a line of contact along the profile that guarantees the seal between them. This movement creates an airtight chamber that shifts with a helical movement, from the suction casing to the delivery casing.
The Diamond series features a patented universal pin joint that ensures top performance and unprecedented flexibility of use. The standardization throughout the entire range of products achieved with this joint has resulted in optimal spare parts management as well as simplified and economical maintenance, without sacrificing reliability and long life.

 

POSITIVE DISPLACEMENT PUMP > PROGRESSING CAVITY PUMPS IN DETAIL

Screw pump due to the small dimensions of the high, allow the pumping of the product without pulsation and keep the fluid unaltered without damage it. Accept the presence of

solid parts and can be suitable to pump fluid with viscosity up to 1.000.000 cps.

Monopump section

PROGRESSING CAVITY PUMP COMPOSITION

 


ROTOR

It is a screw shape with circular section and, rotating in to the stator, allows the pumping of the fluid. The pressure of the pump depends on the number of stages. Every stage gives a pressure of 6 bar. Nova Rotors has two types of rotors: standard and long step type that, considering the same diameter and eccentricity, doubles the capacity increasing the pump performance.

 


STATOR

It is the fixed part of vulcanized rubber, contained or less on the metal tube, shaped like a circular screw quarry where the rotor rotates.

Short step type / Passo corto

Long step type / Passo lungo

 

 

 

 

uniform rubber wall thicknesses / Statore a gomma di spessore uniforme

 

 

 

 

 

 

 


TRASMISSION AND JOINT

Support the axial force and the transmitted torque between rotor connection and drive.

 


BODY PUMP

It is the structure where the liquid is pumped from. Available with a lot of connection types .

 


MOTORISATION

These are the devices that give the movement to the pump: motor, hand variator, gear reducer, inverter.

 


COUPLING

These are the devices that give the movement to the pump: motor, hand variator, gear reducer, inverter.

Close Coupled

dn

 

 

Type J Bearing Housing

jn

 

type F Modular Bearing Unit

fn

 


SEAL:

Is the connection between the fix part and the rotating part of the pump to prevent the exit of the medium. The selection of the type is depending from the fluid to pump.