HZ Series
- Overview
- Features & Benefits
- Specifications
- Other Info
Overview
Dickow’s HZ Series are multi-stage centrifugal pumps designed for handling liquids in industrial and municipal water supply, for handling condensates, boiler feed water, fuels and for various other applications. Impellers are centred inside diffusers of multi-flow channel design converting part of the generated speed in the impeller into pressure. The guide vanes on the back side of the diffusers lead the pumped liquid to the impeller eye of the following stage.
The performance range covers capacities up to 500 m³/h and differential heads up to 380m with a maximum operating temperature of 180°C.
HZA models have an end suction design developed for operating conditions with low NPSHA-values. The wear resistant SiC-sleeve bearing on the suction side reduces the maintenance costs because there is no second mechanical seal required.
HZAR models, of similar design to HZA, have an oil lubricated bearing bracket, type HZAR. The oil bath is protected against the atmosphere by a labyrinth seal. Oil level is controlled by a constant level oiler and an additional sight glass. The bearings are rated for 25000 operating hours.
With several shaft sealing systems available, HZ Series pumps are suitable for handling almost all kinds of liquids which are free of abrasive solids and of suitable viscosity.
The closed impellers are hydraulically balanced by wear rings and balance holes in the impeller hubs. The ball bearings are only carrying the residual thrust loads. Further balancing devices are not required. In applications involving the handling of volatile liquids such as condensate, hydrocarbons or liquified petroleum gases, the problems of cavitation can be reduced by using HZA pumps fitted with impellers with an enlarged eye in the first stage. HZ-pumps with a vertical inlet have slightly higher NPSH-values.
The seal chamber of the pumps is designed to accept all common mechanical seal brands and types. With the sleeve bearing provided on suction side, no second shaft sealing – typical design for multistage pumps – is required.
