How to Select a Flexible Impeller Pump

What is a Flexible Impeller Pump?

Flexible Impeller Pumps are characterised by their unique construction and impressive technical specifications. These pumps, also known as Flexible Vane Pumps, feature an impeller made from high-quality rubber, complemented by vanes housed within the pump. This design feature means the pump can effortlessly handle thin and viscous fluids, and solids in suspension. The simple construction features only a few moving parts which in turn reduces downtime thanks to the simple maintenance requirements.

Advantages of Flexible Impeller Pumps:

All Tapflo Flexible Impeller Pumps can be fitted with food-grade mechanical seals and impellers for enhanced hygienic standards. Some key benefits of using Flexible Impeller Pumps are:

• Flexible Impeller Pumps are highly customisable and can be tailored to suit specific operational requirements
• Ideal for shear-sensitive viscous products and those with solids in suspension
• Reversible operation
• Self-priming capabilities
• Suitable for emptying sumps, tanks, drums, and IBCs
• Delivers pulsation-free flow for filling, dosing, and filtration applications
• While these pumps are not ATEX-rated a standard, ATEX-rated motors are available on request

Common industries & applications:

• Oenological
• Food
• Chemical
• Cosmetics
• Pharmaceutical

What are your fluid & media transfer characteristics?

To choose the appropriate Flexible Impeller Pump for your application, ask yourself the following questions:

1. What media will be pumped? Consider the chemical composition of the media you will be pumping – is it chemically neutral or corrosive, shear sensitive etc.
2. What is the viscosity of the media you intend to pump? Consider viscosity limitations, shear sensitivity etc.
3. Do you need to pump fluids containing solids?
4. Is your environment or fluid explosive?
5. Do you require CIP/SIP?
6. Do you require self-priming capabilities

Impeller Materials Available:

• NBR: Excellent resistance to Oils & fats, FDA-approved
• CR: Ideal for chemical and mechanical resistance
• EPDM: Used for hot liquids and CIP, FDA-approved, ideal for acids and alkalis
• NR: Best mechanical resistance, ideal for room temperature water-based fluids
• VMQ: Used for high temperatures with low mechanical resistance

Some of our materials offer an ATEX option on request for explosive applications and environments.

Maintenance required to keep your Flexible Impeller Pumps running:

• Visual inspections of the casing, impellers and vanes to check for signs of leaks or damage
• Ensure proper alignment of the shaft
• Ensure the shaft seals and gaskets are replaced if worn or damaged
• Grease/lubricate bearings and shafts
• Inspect electrical wirings and connections for signs of damage
• Ensure flows and pressures are accurate
• Listen for excessive noise as this could indicate a mechanical issue

Depending on the size of your pump and the fluid you are pumping, a more detailed maintenance schedule may be required.

Additional Factors to Consider:

Will your pump be stationary, or do you need it to be portable? If you require portability, Flexible Impeller Pumps can be fitted to trolleys of any size to suit your needs.

Related Articles:

• EP Self Priming Flexible Impeller Pump Guide/FAQ
• Flexible Impeller Pumps and their Benefits
• Flexible Impeller Pump for Non-Alcoholic Drinks Case Study
• Flexible Impeller Pump Skid System Case Study