Submersible wastewater pumps are an integral part of efficiently transporting sewage from one station to another in urban areas, with the sewage eventually ending up at a STP (Sewage Treatment plant) ready for processing.
These workhorses are out of sight and out of mind and situated all over towns and suburbs at regular intervals to accommodate mains sewage collection. There can be many hundreds to thousands of submersible pumps that a large council or water authority can have the responsibility for. Anyone that has been in the industry for any length of time will know that it is not all smooth sailing with pumps. Sometimes, when things go wrong, it can result in a less than spectacular and unwanted overflow event that no one either needs or wants to experience. Typically, these overflow events result in a biologically hazardous, unsightly and pungent situation. This must be cleaned up as quickly as possible to prevent any contamination of sensitive biological habitations such as seas, rivers and creeks; not to mention private properties and public areas that are also very politically sensitive.
These events will not only cause hazardous environments to become a reality, they can also be costly to fix, which is why it is important to have a system in place that not only knows when such an incident has occurred, but may also be able to be prevented from happening in the first place.
It is quite normal that the sewage well column level has to be kept over the height of the pump to effect cooling of the pump sets and to stop cavitation so at no time, can you actually hear or even see the pumps.
There are two main reasons why submersible pump sets breakdown. One is bearing and seal failure and the other is ragging or choking events; with the latter being extremely common.
• Bearings faults normally take place over a long period of time, but it is also dependent on the number of peak events where pumps ingest foreign materials.
• Ragging and choking events are possible at any time. All it takes is for someone to flush something down a toilet. The list of articles that can be found inside these pump sets after these events, if it wasn’t so serious can be quite comical. The standard articles apart from the norm are towels, underwear, sleeping attire, partially full plastic bags through to false teeth and from our last account; a full can of tuna was even found.
If you ask any service technician looking after their fleet of pumps, all of them without exception will have stories about what they have found in the pump sets. All these articles can lead to serious damage and even stall the pumps. That is why we have created a system to monitor submersible pump systems.
How is it possible to get conditional data of the pumpsets condition?
Permanent on-line vibration monitoring; in addition to other methods currently used that determine a pumps status, for example flow quality. A high IP rated accelerometer, either mounted internally or externally to the pump set and connected to our on-line diagnostic vibration monitor could well have exceptional results in collecting crucial data for adding into your systems network. Data collection is valuable and important for monitoring and trending the system. Some pumps are even fitted with reversing modules, to try to eject the foreign objects that affect your system.
By utilising the vibration system, a maintenance technician can view these events and the corresponding results to see whether the pumps path has been cleared or not, making it a useful tool for pump monitoring.
There is a software that will enable the user to utilise the information more efficiently. It can be viewed on a PC, a phone or tablet allowing a technician to visualise and track the operating condition of all pumps, even when something out of the ordinary occurs.
The program can be instructed to send an alarm either as an SMS or an email to the people that need to know that an event has occurred. The alarm condition can be opened to see what caused the event, including the option of a graphic that offers a snapshot of the offending monitored object in trend form, along with its amplitude.
A link will be sent for the client to open and will take the user directly to the alarm page whereby they can see what led to the alarm condition. It is even possible to record spectral waveforms at the initial start of the alarm for review.
These type of systems highlight these conditions, so a team can be sent to correct and rectify the offending event, before it turns into a major problem.
This type of system can also run totally independent of any other control system or can be incorporated into an existing SCADA or PLC system.