The world of positive displacement pumps is very large and steadily growing. As a positive displacement pump supplier in GA, I’m often asked about the various types of pumps that are available.
A positive displacement pump supplier in GA has to be familiar with a large variety of high-pressure pump technologies in order to design a system that will emulsify or homogenize fluids. High pressure is defined as anywhere from 300 psi to 10,000 psi. Once you get into this pressure territory, you are outside your typical material transfer pumps. A small sampling of low-pressure pumps would include:
- Centrifugal pumps;
- Lobe pumps;
- Pneumatic Diaphragm pumps;
- Solenoid Piston pumps.
Practical experience leads to choosing the right pump or how to design a system around such a pump.
High-Pressure Positive Displacement Pumps in GA
Once you start emerging into the world of high pressure – above say 300 psi – your options are limited and things like fluid viscosity begin to play a more significant role.
Rotary Gear Pumps: At 300 or 500 psi you can use rotary gear and pumps by manufacturers like Viking Pump. These pumps use 2 rotating gears set inside a housing with fairly tight tolerances between the gear outer edges and the housing inner wall. The tighter the tolerance between these surfaces, the more pressure the pump can theoretically handle.
These pumps typically have a difficult time pumping water-like viscosities even though their pump curves are based on water. These pumps perform better with higher viscosity fluids because there’s less chance the fluid will slip outside that gap between the gear edge and inner housing wall.
The slip is fairly significant and something to think about because with that slip comes a lot of noise. The pumps hammer and bang when struggling against these high pressures and low viscosities. If you are pumping water-like viscosities at these pressures, these might not be the best pumps for you.
The nice thing about these pumps, however, is that they typically come in sanitary or hygienic designs good for pharma and personal care.
Progressive Cavity Pumps: Progressive Cavity (PC) pumps are another option at this pressure region of 300-500 psi. These pumps use a long spiral-shaped auger that rotates inside an elastomeric stator and moves fluid progressively along the auger. Slip can occur in a similar manner at the space between the rotating auger and the stator.
The good news with these pumps is that there is no real gap between the rotating and stationary components because the metal rotor can essentially make contact with the elastomeric stator. Now slip occurs due to compression of the elastomeric element. These pumps handle water-like viscosities much better than the rotary gear type, but suffer flow losses due to intake efficiency drops when the viscosity is high.
Reciprocating Triplex Plunger Pumps: These pumps work in a completely different manner altogether by actually trapping material between a set of checking valves where it’s nearly impossible for fluid to migrate or slip back. The problem here is that these pumps cannot handle higher viscosity fluids much above 3000-4000 cps. However, they are easily cleanable, but do not bear those certificates. Improvements can be made to handle higher viscosity by using a feed pump to pressurize the inlet. These pumps can accommodate really high pressures now in the 10,000-psi range.
All told, it’s not as simple as Googling positive displacement pumps to find what you want. You’ll get 973,000 results ranging from storefronts for mini vane pumps to obscure images of homemade pumping systems.
With the Internet’s overabundance of information, it’s time to seek a connection with a trusted positive displacement pump supplier in GA. We want to be yours – call our office today and our experts will be happy to assist you.