- Case Study Summaries
- Flygt Sanitary Lift Pump
- ABS Process Fluid Aeration
- KJI Stormwater Pumping
- Worthington Boiler Feed Pump
The Hydro Companies have provided pump services and support to the municipal market since 1969. Unlike many of the small, local repair shops that often service this market, Hydro has a very strong engineering background. As a service company, we are solution based rather than product based. Click the links on the left to see how Hydro has provided solutions to the municipal market.
"I have been supporting the municipal industry for the past 30 years. In those 30 years, I have been involved in pumps and wells in both the water and wastewater sides of the industry. I have worked as an employee and a service provider in the municipal market which has given me valuable insight from both views. Before I joined Evans-Hydro, I used them as a supplier and personally saw the difference in their quality approach which lowered the district's overall cost of ownership and increased longevity of their pumps. It was this, the Hydro team and an opportunity to better myself that drew me on board. When I go to visit a customer, I know from experience that Hydro can offer them the best solution for their pumping needs."
Paul Walton, Sales & Service Representative
Evans Hydro, Inc.
Flygt Sanitary Lift
Application: Sanitary Lift Station
Pump Details: 290hp Flygt 42” Diameter Submersible
Pump Type: Submersible Axial Flow
A large axial flow pump from a municipal sanitary district was sent to Hydro after exhibiting extremely high vibration. Hydro’s submersible pump repair team determined that a large chunk of concrete debris from nearby sewer construction had caused the failure. The municipality faced a lead-time of 14 weeks for a new impeller from the OEM, but they could not afford to have this pump out of operation for that period of time.
The sanitary district accepted Hydro’s offer to repair the impeller so the pump could be in service temporarily until a new impeller could be obtained. A stainless steel impeller hub was fabricated then pressed and bolted to the impeller body. The impeller vanes were repaired, the bore machined, the inlet neck machined and a stainless steel wear ring manufactured and installed. After the impeller was balanced and coated with a ceramic epoxy, new bearings and a mechanical seal were installed. The job was completed in only 3 weeks.
Hydro received this same pump for normal overhaul five years after this temporary solution was implemented and learned that the work done in the previous repair allowed the station to continue to produce over 25 million gallons a day at full speed for those five years.
ABS Process Fluid Aeration
Application: Aeration of Process Fluids
Pump Details: 115hp ABS Channelaire
Pump Type: Submersible Aerator
Wastewater, which tends to be very corrosive and abrasive, must be cleaned before being discharged into lakes or rivers. Aerators are used to inject air into the liquid to sustain biological growth, enabling bacteria to eat oil and other contaminants in the wastewater. This 115hp aerator experienced abrasive wear of its 316 stainless steel channel ring and motor mount when wastewater entered the motor and shorted the stator. Hydro rewound the stator, weld-repaired the channel ring and motor mount, and installed new cable entry assemblies. In addition, Hydro provided O-rings, grommets, lubricants, upper and lower seal assemblies, upper and lower bearings, a new impeller wear ring and a leak sensor for the junction box.
After checking the sensors and performing a no-load motor test, Hydro returned the repaired unit. Total cost of the repair was only 28% the price of a new unit. The unit was delivered in half the time it would have taken a new unit to arrive.
KJI Stormwater Pumping
Application: Stormwater Pump Station
Pump Details: KJI Models KWM 100hp & KSE 60hp
Pump Type: Mixed Flow & Guide Rail Submersible
With the continued growth and development of a downtown area, it's natural to see an increase in water flow into the pumping stations whose purpose is to prevent expressway flooding. When an independent engineering firm identified the need to increase a pump station's capacity, Hydro was selected to conduct the retrofit project.
Having purchased one 60hp low flow submersible pump and five 100hp mixed flow pumps from Hydro’s KJI submersible line, the station planned to replace the 40-year old vertical turbine pumping system. Five custom 41” long draft tubes had to be set into place, which required precisely fitting each through a skylight. The final installation spanned three separate floors. The pump station could not be altered in any way to accommodate the transformation and existing I-beams, which presented four 'pinch points' to be evaluated before the removal of the existing pumps and installation of the new pumps.
Hydro’s engineers produced a 3D CAD representation of the existing station and the new draft tubes to conduct a 'virtual reality' installation in cyberspace. This 'virtual' installation paved the way for a smooth, trouble-free retrofit in which this pump station was able to continue supporting over 100,000 cars, trucks, and motorcycles which depend on the roadway every day.
Worthington Boiler Feed
Application: Boiler Feed in WAO Process
Pump Details: Worthington 2WXL 810
Pump Type: Multi-stage Segmental Diffuser
These boiler feed pumps, used in wet air oxidation process, were exhibiting reduced performance. The plant sent these pumps to several repair facilities, but did not achieve significant improvement. Hydro was asked to perform a comprehensive inspection and created an engineered repair plan to solve the problems.
Hydro corrected many problems with these pumps, some which were caused by poor-quality previous repairs. Hydro reinstalled bearings with the proper clearances and brought the wear ring clearances back to acceptable tolerances. The pump shaft was replaced and the tolerances between the impeller bores and pump shaft was tightened. Impeller entrances and exit vane tips required restoration for proper hydraulic profile. The sleeves and casing wear rings were replaced with the correct metallurgy, heat treatment hardness and clearances. Each impeller was individually balanced to 2W/N and then the entire rotor was balanced to 2W/N.
Hydro also reviewed the pump installation for piping strain and alignment problems that could adversely affect MTBR. Many of the pumps had been shimmed to match the motors, rather than rigidly mounting the pump to the base. Hydro machined the base plate pump pedestals for rigid mounting.
Hydro's engineered rebuild of these older boiler feed pumps allowed this plant to not only restore performance but to realize a substantial cost savings.