Twin-screw pumps 2VV, 2VG

Twin-screw pumps of 2VV and 2VG and electric pump units on their base are intended for pumping nonreactive liquids within a wide range of capacities.

Pumps being parts of the electric pump units are related to the items of general purpose (ION) aspect I (repairable ones) as per GOST 27.003 90, and are manufactured in climatic version U, location category 2 as per GOST 15150-69. At the Customer's request it is possible to manufacture pumps in another climatic version. In design work the safety requirements as per OST26-06-2028-96and also the norms and rules of Rostechnadzor (Russian Technical Supervision) as per PB08-624-03, PB09-540-03, PB09-563-03 have been taken into account.

Pumps are admitted for servicing in dangerously explosive zones V-1а, V-1b, V-1g, according to PUE (Electric Installation Code) with the mediums having explosion hazard category IIA, IIV as per GOST R 51330.11-99, inflammability group – Т1, Т2, Т3, Т4 as per GOST R 51330.5-99.

Pump unit consists of twin-screw pump and electric motor mounted on a common foundation frame. Connection between motor and pump is made through the sleeve coupling.

Pump – is a positive displacement, horizontal machine. Two synchronously revolving rotors having special thread are arranged in the bores of the pump shell. Replaceable shell is inserted into the pump casing. Rotation from the driving rotor is transmitted to the driven one via the timing gears. Rotors are supported by bearings taken outside from the hydraulic part of the pump.

The casing of the pump made in heating version (2VG) has a chamber intended for heating (cooling) of the casing by heat medium.

At the butt ends the working chamber is closed by bearing bodies, and the shafts are sealed by end-face seals or by stuffing material.

At the Customer's request the units may be completed by soft start device, frequency converter, control & protection systems.

• in technological processes of oil refinery in petrochemical plants for a pumping of mazut, tar, vacuum gasoil
• for pumping/transfer of oil products by sea and railway transport terminals
• for ensuring technological and auxiliary processes connected with pumping of oil products by industrial enterprises
• pumping of water, polluted by oil products, from drainage capacities at the oil refining enterprises and transportation of oil products

2VV:

• possibility of repair with replacement of repair packing and saving of parameters
• equalized liquid flow without pulsation and mixing and able to save its structure
• pumping liquids with the wide viscosity range
• good suction capacity = up to 5 m and more, depending on pumped liquid viscosity
  

2VV:

• heating jacket
• equalized liquid flow without pulsation and mixing and able to save its structure
• pumping liquids with the wide viscosity range
• liquid temperature up to 150...200°С
• single or double mechanical seals
• material selection (carbon or stainless steel) enable handling various liquids such as oil, petroleum, fuel oil, and also chemically active liquids
• good suction capacity = up to 5 m and more, depending on pumped liquid viscosity
• safety valve for protection from high pressure is optional

For example А2 2VV 10/16-6/6,3B U2, TU 3632-064-05747979-99, where:

• А2 – design code of the pump: А1 – welded casing, replaceble shell and single end-face seal; А2 – cast casing and single end-face seal; А4 – welded casing, replaceable shell and single end-face seal; А7 – welded casing, replaceable shell and stuffing box seal
• 2VV 10/16 – pump designation as per GOST 20572-88
• 6 – capacity of the pump when coupled with the motor at pumped liquid viscosity of 1*10 6 m²/s (1°E), m³/h
• 6,3 – pressure of the pump when coupled with the motor at pumped liquid viscosity of 1*10 6 m²/s (1°E), kgf/сm²
• B – material of pump flow passage: А – steel, К – chrome-nickel steel, B – bronze
• U – climatic version
• 2 – location category