The submersible sewage pump is a pump-motor integration working in a submersible way. Compared with common horizontal pumps or vertical sewage pumps, the submersible sewage pump has the following noticeable advantages:
Compact and space-effective: The submersible sewage pump works in a submersible way, so it can be mounted in the sewage sump directly, unnecessary for building a dedicated pump room to mount pumps and motors, thus saving a lot of expenses for land and capital construction.
Easy for installation and maintenance: A small-size submersible sewage pump can be installed freely while a large-size one is provided with an automatic coupling device generally for automatic installation, thus quite easy for installation and maintenance.
Available for long-time continuous operation: As for a submersible sewage pump, its pump and motor are coaxial, with a short shaft and a light rotary assembly, so that the load (radial) on the bearing is relatively small, thus its life is much longer than that of common pumps.
Free of such problems as cavitation pitting and pouring of diversion water. In particular, the latter facilitates operators a lot.
Low vibration noise, small motor temperature rise and being environment-friendly.
It's because of the above advantages that the submersible sewage pump has been catching more and more attention and applied in an increasingly bigger scope: transporting from clear water in the past simply too different kinds of domestic sewage, industrial effluent, drainage of construction sites, liquid feedstuff and others at present. It plays a vital role in all walks of life, like municipal works, industry, hospitals, buildings hotels and water conservancy construction.
However, every coin has two sides. As for the submersible sewage pump, the most critical question is its reliability: because it's used in a submersible way; some of media it transports are liquid mixtures containing solid materials; the pump is very close to the motor; and the pump adopts a vertical arrangement so that the weight of the rotary assembly has the same direction as the water pressure borne by the impeller. All of those issues result in higher requirements for the submersible sewage pump than common sewage pumps in such aspects as seal, motor bearing capacity, bearing arrangement and selection.
To improve the submersible sewage pump's life, at present most manufacturers, both at home and abroad, are seeking ways for the pump's protection system, that is, the system can alarm and stop the pump for repair automatically in case of such faults as leakage, overload and overtemperature. We think it's rather necessary to set a protection system for the submersible sewage pump because the system can protect the electric pump for safe operation effectively.
However, that's not the crux of the matter. The protection system is just a remedy after the pump goes wrong, which is a passive measure. The crux shall be focused on the cause to solve the pump's problems thoroughly in such aspects as seal and overload. That's an active way. Therefore, we applied the auxiliary impeller fluid power seal technology and the pump's overload-free design technology to the submersible sewage pump, thus improving the pump's seal reliability and bearing capacity substantially and extending its service life.