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 Turn key projects for the oil/gas industry
Complex Equipments
Drilling and production tools
Containers/Caravans/Portable Cabines
Transportable gas stations
Gas Compressor Electric
Workover Unit AM 10
Progressive Cavity Pumps
Reservoirs,vessels
Metallic Structures
Sucker Rod Pumps Parts
Rubber Parts for Oil/Gas Industry
Thermo units
Manual actuators
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 PROGRESSIVE CAVITIES PUMPS
From 2000, SC CONFIND Campina manufactures and delivers pumping units with eccentric screw pumps and rubber stator. These units are
produced in partnership with KACHELE of Germany, the most important world producer of stator-rotor sets for eccentric screw pumps,
also known under the name of PCP Progressive Cavity Pumps
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 Operation Principle : the eccentric screw
pumps have two active elements :
a steel rotor and a rubber stator.
The rotor is in the shape of a one-head screw. In cross-section, the rotor profile is a circle, with the center on a cylindrical helix.
The stator is a two-head helical surface, with the front profile made up of two circles arcs of the same radius as the rotor, connected to two straight
segments.
The rotor and the stator close a lens-shaped space which is moved axially in the engagement of the rotor inside the stator : one step stator movement by each rotation.
Outlet pressure :
The pump with a single step-stator provides pressure up to 6 bar. At pressures higher than 6 bar/step-stator, the hydraulic output drops.
For the two-steps-stator pumps, it is 24 bar and for the 8 steps-stator, it is 48 bar.
For pumps with pressures over 48 bar, KACHELE has developed stators with helical metal support (jacket). In section, the contour of the metal jacket
follows the work space of the stator and the elastomer layer is of constant thickness.
For the pumps with stator with helical jacket, pressures of 9 bar/step-stator are allowed. In such conditions, CONFIND-KACHELE produce
pumps for up to 100 bar, with monolith stator.
The pump output is determined by the stator-rotor set eccentricity, diameter of the rotor's circular section diameter, step, tightness between stator and rotor,
pressure and rotation speed.
Movement of liquid flow determined by the rotor
The pump characteristics express graphically the connections between the main operating parameters.
We present below the characteristics in the stators of two types of pumps (sets of 50-4 and 60-4, respectively, with the rotor section Ø 50 and Ø 60,
with 4 steps-stator) at various speeds.
The connection flow rate-outlet pressure for several operating pressures is highlighted. The limits imposed by the electric motors are also indicated. The CONFIND
technical specifications (catalogs) present graphically or in table-form the constructional characteristics of pumping units at various rotation speeds, the flow
rate and the power absorbed by the motor for various outlet pressures.
Materials : to keep wear as low as possible even in the pressence of solid
particles in suspension and the drops in time of the flow rates insignificant even after a long period of operation , the following materials are used :
Genneraly, the rotors are made of stainless steel and their working surface is chromeplated (hardening the surfaces).
The stator elastomer is selected according to the characteristics of the liquid to be pumped. These precautions are taken by KACHELE, an expert in elastomers for the
widest range of applications. The stator elastomer is adapted to the concrete operating conditions of the pump : fluid transferred, its temperature, contents of solid
particles.
In regular production, the elastomers used allow temperatures up to approximately 70 °C . For special production, stators made of elastomers for operating
temperatures up to 170 °C can be provided. The other parts which have contact with the transferred liquid are zinc-coated in normal uses, or with a hard chrome
plating or stainless steel when used for aggressive fluids (e.g. salt water).
 Details PROGRESSIVE CAVITIES PUMPS
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