The new stator material named Alldur was specially developed for use in sewage treatment plants and for pumping abrasive wastewater. The elastomer’s new chemical composition and production methods can increase service life by up to three times. Alldur stators are now available in all Allweiler brand progressing cavity pumps.
Colfax Fluid Handling’s Allweiler plant in Bottrop, Germany, manufactures approximately 8,500 progressing cavity pumps for sewage treatment plants every year. For more than 50 years, the Bottrop plant has been one of Germany’s leading producers of PC pumps, a design that is optimized for use in wastewater treatment. The Allweiler brand is one of the few manufacturers that produces nearly every part of its progressing cavity pumps at its own plants in Germany. Stators are particularly important and must be carefully matched to the pumped liquid. According to Elvis Kovačević, manager responsible for progressing cavity pumps: “We choose from twenty combinations of elastomers so the customer gets one of the most economical solutions possible.” The new “Alldur” stator can stay in service for up to three times longer than other stators.
The composition of “Alldur” is adapted to provide maximum resistance to mechanical influences. “Wear is incredibly low, even when the pump moves highly contaminated wastewater with a high proportion of solids for long periods of time,” according to Alfred Paul, director of development. The new stator is also highly elastic and exhibits high tensile strength. It has high tear-growth resistance and can be used across a wide temperature range.