Leak Free Pumps for the Toughest Situations
The established range of self-contained, leak-free Nikkiso Canned Motor Pumps has been extended with the introduction of the HK Series, a high head, high speed version of these sealless centrifugal pumps. Available through liquids handling specialists MICHAEL SMITH ENGINEERS, the HK series provide capacities to 14.5 m3/hr, heads to 290 metres at speeds to 8400 rpm.
The canned motor pump, originally designed to meet zero leakage and maximum reliability demands of the nuclear power environment, is now widely used in general industry. In particular, they excel in applications involving aggressive, inflammable, explosive and toxic clean liquids because of the important advantages they offer over conventional centrifugal pumps.
For example, the construction of the Nikkiso pump is hermetically sealed and provides primary and secondary fluid containment i.e. the process fluid would need to breach TWO separate physical stationary barriers before any leakage from the pump / motor unit can occur. Also, as there is no external shaft on a canned motor pump, there is no need for any costly and troublesome on-site shaft alignment, unlike conventionally sealed or long-coupled mag-drive pumps where alignment between the pump shaft and motor seal is required. As the pump and motor are combined in a canned motor pump, the number of wearing parts is reduced, thereby reducing the stock of spare parts required.
HK Series pumps are supplied in a compact, yet robust, two-stage design in tandem arrangement with speed control via an external frequency inverter.
They are therefore much smaller than comparative multi-stage pumps covering the same performance envelope and tend to be much more efficient and quieter. With this increased efficiency, the HK pump is therefore not only economically priced compared to a multi-stage or side channel pump but also offers reduced operating and maintenance costs.
Other features and benefits include, an axial thrust balance system for long bearing life, minimal maintenance and low NPSH R and if required the option of ATEX flameproof canned motor versions.
Typical applications for these pumps include use in vacuum systems, reverse osmosis units or wherever leak free pumping of low volumes of expensive, aggressive, corrosive or inflammable liquids at high pressures need to be transferred with optimum safety and efficiency.
Source: Michael Smith Engineers