Flexible Performance

The regenerative turbine pump is a rotodynamic pump that combines the high discharge pressure of a positive displacement (PD) pump with the flexibility of a centrifugal pump. They excel at transferring fluids with high pressure, low flow and low viscosity while handling entrained vapors or fluids at or near their boiling point. These fluid conditions generally hamper the performance and reliability of most pump technologies, but regenerative turbine pumps maintain their efficiency in any pumping and fluid conditions, eliminating the damaging impact of cavitation and pulsation.

Regenerative turbine pumps are known as turbine pumps, peripheral pumps, centrifugal regenerative pumps, regenerative pumps and many other names.

New to regenerative turbine pumps, go interactive now with our online tool. See what’s happening inside an Ebsray RC40 Regenerative Turbine Pump with exploded and cutaway views.

Regenerative Turbine Pump Interactive Tool

How Do Regenerative Turbine Pumps Work?

Though considered rotodynamic pumps, the operation of regenerative turbine pumps more closely resembles that of a PD pump. They operate using an impeller that is a rotating, non-contacting, freewheeling disc that has many small buckets or cells (typically about 60) on its periphery. When liquid enters the suction port of the turbine pump it is picked up by the impeller and instantly accelerated around in the narrow hydraulic channel (casing volute) surrounding the cells.

The spiraling – or ‘winding-up’ – of the liquid many times (at sonic speeds) within the one revolution incrementally builds energy/pressure. This ‘winding-up’ of the numerous small liquid cells creates the differential pressure capability of the pump – hence the name regenerative turbine pump.

Regenerative Turbine Pumps “How it Works” Animation

Design Benefits of Ebsray Regenerative Turbine Pumps

For more than 75 years, Ebsray has built a reputation as the leading developer and supplier of industry-standard regenerative turbine pumps. The secret to the success of Ebsray Regenerative Turbine Pumps is the innovative impeller design, which optimizes hydraulic performance resulting in high differential pressures even at low flow rates, a critical consideration for LPG applications. The pumps feature a compact design with few rotating and wearing components, which eases maintenance and repair demands. Other design benefits include:

  • UL/CE/ATEX compliant
  • Diminishes the damaging effects of cavitation by smoothing the fluid through gentle collapse of vapor bubbles
  • Excellent self-priming and vapor-handling abilities
  • Operates without vibration and noise in all pumping situations
  • Smooth, pulsation-free discharge of fluid that is gentle on the whole pump system
  • Maximum allowable working pressure to 34 bar (493 psi) for handling liquids with high vapor pressures
  • Repairs can be performed in the field
  • Can handle viscosities of 0.1-50 cSt
  • Low net positive suction head required (NPSHr) for difficult suction conditions with low net positive suction head available (NPSHa)
  • Small, compact footprint when compared to competing technologies
  • Single-stage pump engineered to perform reliably and safely at motor speed
  • Wide performance range within various conditions allows for system flexibility
  • Increased flow rates and faster loading/unloading times when compared to other pump technologies

Regenerative Turbine Pump Applications

  • LPG
  • Propane
  • Butane
  • Autogas
  • Ammonia
  • Cylinder Filling
  • Aerosol Propellant
  • Vaporizer Feed
  • Boiler Feed

Ebsray Regenerative Turbine Pumps Vs. Competitive Regenerative Turbine Pumps

When compared to competitive regenerative turbine pump brands and models, Ebsray Regenerative Turbine Pumps stand out by providing numerous inherent advantages that result in a smooth, quiet operation and long pump life. Among these advantages is the ability to generate flow rates up to 600 L/min, which dwarfs the competition that can only produce 100 L/min. Ebsray pumps are also more efficient and cost-effective since they require a smaller motor size to perform the same duty. Additional benefits include:

  • Operates without a Best Efficiency Point (BEP) for PD-pump performance curve flexibility
  • Durable design for continuous-duty operation
  • The mechanical seal is the only wear component
  • Less complex to operate, maintain, repair and rebuild, with easy seal and impeller access
  • Less operational costs due to a smaller motor than competitive brands
  • Easy installation with no additional adjustments to maintain performance
  • Motor interchangeability for flexibility in motor options

Examples of Regenerative Turbine Pumps Vs. Competitive Technology

graphic_centrifugal-pump

Centrifugal Pumps

Unlike regenerative turbine pumps, the centrifugal pumps used in LPG handling are not self-priming unless they are submersible; however, the main shortcoming of them when handling LPG is that they are prone to experiencing vapor lock. Another area of weakness for centrifugal pumps is the NPSHr. Traditional centrifugal pumps, either single or multi-stage, have relatively high NPSH requirements. When dealing with liquids at a boiling point, NPSHa is normally very low, which leads to cavitation and premature failure of the pump with damage to impellers, mechanical seals and bushings or bearings.

side-channel

Side-Channel Pumps

While side-channel pumps are self-priming, the main disadvantages of these pumps are in terms of size, maintenance complexity and relatively high capital cost. Specifically, side-channel pumps, when used in LPG-handling applications, may require 4 to 8 stages to work effectively. This many stages increases design complexity, which makes them difficult to maintain. Side-channel pumps also require a large installation footprint in order to accommodate both the pump and its motor.

sliding-vane-graphic

Sliding Vane Pumps

While more effective than centrifugal and side-channel pumps, sliding vane pumps can’t quite meet the same performance standards as a technology such as regenerative turbine pumps when handling LPG.