AxFlow eccentric spiral pumps

A discussion covers the properties of the eccentric spiral pump, a challenge it poses, and an approach to solve it by Mono Pumps Ltd. The eccentric spiral pump is widely used to pump abrasive or viscous non-lubricating liquids. The conventional eccentric spiral pump connects the rotor to the pump shaft by a linkage and the pump shaft is sealed by a packing gland. Many media have small hard particles that abrade the stator, rotor, and linkage early on. This results in frequent maintenance, high replacement and storage costs, and unplanned downtime. An eccentric spiral pump has three wear zones, the rotor and stator, the linkage between rotor and pump shaft, and the shaft seal. The wear between the rotor and stator can be reduced by coating the rotor with a hard ceramic. The ceramic has a smoother and harder surface than chromium plated rotors and the advantage of the stubborn stainless steel parent material. This rotor surface is matched with a stator surface of an especially soft material. The wear of the linkage can be excluded by use of a flexible shaft. This so-called Flexishaft is made of highly bendable material making linkage connections superfluous. Wear parts are eliminated. By its pliability the Flexishaft changes the eccentric motion of the rotor into a centric motion. The Flexishaft does not need to be lubricated, eliminating contamination to the material being pumped. Replacement parts and maintenance costs are reduced. Instead of a packing, a special sliding packing ring in most cases affords a longer service life. The insertion of the most varied sliding packing ring manufacture is possible according to DIN.