KSB Australia announces that a new generation of hot water recirculation pumps will be launched in June 2014.
To be introduced by KSB Aktiengesellschaft, Frankenthal, Germany, the new hot water recirculation pumps are designed for large industrial heating systems as well as forced circulation boilers and district heating systems.
Available in 49 different sizes to suit multiple applications, the HPK-L pump series can be operated at temperatures of up to 400°C without any additional cooling devices, and is designed for pressure classes of up to PN 40. This temperature resistance is achieved by means of a generously sized heat barrier, which separates the pump set’s hot operating section from the air-cooled mechanical seal chamber.
The horizontal, radially split single-stage volute casing pumps feature a back pull-out design. Their ratings and dimensions comply with ISO 2858; the pumps also meet the technical requirements of ISO 5199 for handling hot water, organic or synthetic heat transfer fluids.
Key features of the HPK-L series hot water recirculation pumps include fan impeller fitted at the pump shaft end generating continuous flow of air between the large cooling fins surrounding the mechanical seal chamber; service life up to 25,000 operating hours ensured by large, product-lubricated silicon carbide plain bearings fitted close to the impeller and by two angular contact ball bearings in back-to-back arrangement sealed on both sides and mounted at the ‘cold’ end of the shaft; patented venting profile, VenJet ensuring the gas contained in the fluid is separated near the mechanical seal and is collected in the venting chamber; and pump design providing space for installation of double mechanical seals in tandem arrangement without necessitating any changes to the lengths of the cooling distances in the pump.
Discharge-side casing wear rings and drilled holes in the impellers help to reduce the axial thrust as well as the loads on the bearings. The pump manufacturer will also make sure every impeller is matched to the required operating point before the pump is supplied to the customer.