The results show that the steel alloy loses significant weight over time, which is an indication of the pitting caused by cavitation. The Power-Core® impeller, by contrast, exhibits no weight loss, or wear, whatsoever.
Closter, New Jersey (PRWEB) March 31, 2013
A study released this week by Intech Power-Core finds that polymer impellers and pump components can outlast and outperform metals and composites. This experiment studied an impeller made of stainless steel and compared it to a pump impeller running in the same environment but made from Power-Core ® a proprietary cast polymer. The results were impressive showing no-weight loss due to cavitation and erosion wear in the polymer and considerable cavitation damage and erosion caused to the stainless steel counterpart. (see image 1 and Figure 1).
A pump impeller is a classic example of a moving component that can both cause cavitation—and suffer the consequences of cavitation wear. Polymers resist cavitation wear. It may be counter-intuitive, but polymers can actually do a better job than seemingly stronger metals when it comes to enduring cavitation wear. The reason is that inherent elasticity of polymers allows them to absorb the energy released by the collapsing bubbles. Yet, not all polymers should be considered a good fit for applications that suffer from cavitation wear. Keep in mind that cavitation implies a continuous exposure to liquid. And many types of polymers, such as phenolic and nylons, simply will not tolerate liquid exposure for long periods of time—not without dimensional changes or degradation in physical properties. One polymer that can tolerate the long-term exposure to many types of liquids is the cast polymer that serves as the base for Intech Power-Core®.
“While we have long theorized that Power-Core would be an outstanding choice for pump impellers, Casing Rings, hydraulic valves and other components that are subject to cavitation wear, we have lacked the data and calculations to bring them to market. We are pleased to finally have the empirical evidence to substantiate our hypothesis and be able to bring this unique solution to market,” noted Alexander Bartosch - Marketing Director at Intech. "Recently, we backed up our theories with cavitation tests that compared Power-Core® to various chromium-nickel alloy 329 Stainless steels under conditions that simulate those found in high-pressure pumps."
The results show that the steel alloy loses significant weight over time, which is an indication of the pitting caused by cavitation. The Power-Core, by contrast, exhibits no weight loss, or wear, whatsoever.
Intech Power-core Impellers are 1/7th the weight of Steel or Bronze. That means that, because of the strength to weight ratio of the Power-Core Material, Intech impellers require less energy to run and have a lower moment of inertia (less start up load), can improve bearing and mechanical seal life, and ultimately produce less vibration and shaft deflection, thus reducing the costs of replacing a bent or broken shaft or the noise of an impeller running out of alignment. And thanks to the self lubricating properties of power-core they can also run dry without damaging the pump.
Intech Impellers are cast to 100% net shapes and because of the Power-Core material properties yield a perfectly balanced part and maintain that balance over the life of the pump. They also eliminate electrolysis. Power-Core is an inert cast polymer and does not conduct electrolysis and thereby prolongs the life of metallic pump casings.
Power-Core reduces noise and vibration because of the extremely tight tolerances achieved through the proprietary Power-Core casting process. Power-Core impellers are light weight and exhibit excellent vibration dampening and noise absorbing qualities. This ultimately reduces noise and vibration in the pump better than any other material on the market.
To learn more about cavitation wear, download our application note, “A Polymer Solution To Cavitation Wear Problems.”