VNO 25-1200 - The hydraulic part for pumps VNO

Hydraulic part to pumps of VNO type is intended to pump stratal liquid by pumping units with upper drive out of the oil wells with internal diameter of the casing not less than 121,7 mm as per GOST 633—80.

The stratal liquid — mixture of oil, associated water and oil-well gas has the following parameters:

• maximum kinematic viscosity - 1х10-4 m2/s
• maximum content of associated water - 99%
• content of free gas at the pump intake, not more than — 50% by volume
• maximum concentration of solids — 0,8 gr/l
• microhardness of particles not more than 55HRC
• maximum temperature —110° С

Hydraulic part of the pumps of VNO type is a part of the submersible unit for oil recovery. The said unit - is a submersible unit with electric equipment (control station and electric drive), located on the surface.

The hydraulic part consisting of screw-shell pair is lowered separately into the shell: firstly the shell is lowered on the oil well tubing by which the stratal liquid is drived up, then the screw is let down on the rods.

• By oil-extracting companies for production of water-oil mixes from low-viscosity up to hardly flowing, with very high content of sand and gas, at high tightness of operating parts and low production and repair expenses

Advantages of semi-submersible screw pumps applied for oil production:

In comparison with SHGN plunger pumps:

• simple design and compact design of their drives
• no need in foundation
• simple installation and service
• wide range of pumped liquids with various physical and chemical features (high viscosity and gas ratio)
• no reciprocating motion of screw, constant load on the rods, equalized liquid flow, lower power consumption and rated drive power, minimum emulsifying effect on the wellbore fluid

In comparison with UEVN submersible screw pumps:

• simple design of the pump (there are no jointed connections, gas lift valves, radial and axial bearings)
• surface drive motor; no need in cable, hydro protection of the electric motor; motor control and service become simpler)
• operation in wells with low flow rate where is no need for heat removal from submersible electric motor

In comparison with ETSN submersible centrifugal pumps

• wide range of pumped liquids with various physical and chemical features (high viscosity and gas ratio)
• surface drive motor; no need in cable, hydro protection of the electric motor; motor control and service become simpler)
• operation in wells with low flow rate where is no need for heat removal from submersible electric motor

For example VNOМ 20.15 , where :

• VNO – progressing cavity single-entry submersible pump with surface drive and single-threaded screw
• М - letter М denotes multiple - thread operative parts
• 20 – rounded-off minimum capacity of the pump, m3/day, at predetermined head, while pumping oil with a kinematic viscosity ν = 21x10-6 m2/s = 3° E at a rotational frequency of the screw 3,83 s-1 (230 rpm)
• 1500 – head of the pump, m