The flow-rate, viscosity and efficiency advantages of screw pumps make them a viable alternative to centrifugal pumps.
by Josh Pepper & Michael Moore
May 4, 2017
  • Ability to handle a wide range of flows, pressures, liquid types and viscosities
  • Constant flow, even in the presence of varying system backpressures due to viscosity changes
  • High volumetric and overall operating efficiencies, resulting in reduced operational costs
  • Controllable output via variable capacities
  • Low internal velocities
  • Self-priming operation and good suction characteristics
  • High tolerance for entrained air and other gases—a prime consideration in oil production
  • Low mechanical vibration lengthens service life
  • Intrinsically smooth and quiet operation
  • Extremely low pulsation reduces stress and prolongs life of associated fluid-transfer components (piping, hoses, etc.)

Realizing the operational advantages that can be achieved when using screw pumps in oil and gas fluid-transfer applications, some companies have developed products to meet these needs.

One screw pump product line offers twin screw with timing gear (WTG) and triple screw models for oil and gas fluid-transfer activities. The twin screw WTG pumps have been designed with external bearings and a timing-gear transmission, which produces double-suction, self-priming operation with no metal-to-metal contact between the pump’s internal components.

This design helps the twin screw WTG pump achieve the highest flow rates of any rotary PD pump, even at varying backpressures and viscosity levels.

Triple Screw PumpsImage 2. These triple screw pumps are made to handle clean lubricating fluids without solid content across a wide range of viscosities, temperatures and pressures. This method of operation delivers smooth, constant product flow with low noise and high levels of energy efficiency.

The deliverable flow rate of a PD screw pump increases as the fluid’s viscosity increases. These design characteristics also make screw pumps suitable for all types of transfer applications, including low- or high-viscosity, lubricating or non-lubricating, neutral or aggressive, and clean or contaminated fluids.

The triple screw pumps are made to handle clean lubricating fluids without solid content across a wide range of viscosities, temperatures and pressures. They are designed with a male drive spindle, two female secondary spindles and a case that contains the screws, which allows the fluid to move smoothly and continuously in an axial direction from suction to discharge. This method of operation delivers smooth, constant product flow with low noise and high levels of energy efficiency.

Familiarity can provide comfort in a world that seems to be changing much too rapidly. It can be easy to see why operators in the various segments of oil and gas production—upstream, midstream and downstream—have come to rely so heavily on centrifugal pumps for their fluid-transfer needs. It is a technology that has proven over many years to satisfy their demands in optimizing a very complicated production and supply chain.

Screw pumps can be an efficient, reliable and versatile alternative to centrifugal pumps in critical oil and gas fluid-handling applications.

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