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Instrumentation + Get AlertsRetrofit kit used to update faulty actuators
Problem
Water-operated cylinders in the City of Norman, Okla., were antiquated, unreliable and no longer supported with spare parts. The actuator needed modification to accommodate new open/close or modulating inputs that control the valves in the filter gallery.
Solution
The city purchased high-performance rotary vane actuator retrofit kits from K-TORK designed to operate any quarter-turn AWWA valve, such as butterfly, ball or plug valves. While the valve remains in the line, the actuator bolts directly to the valve, replacing the nonperforming equipment. Each kit includes the actuator, solenoid valve, manual override, limit switches, visual indicator, and speed controls or throttling positioner, along with the mount kit to adapt to valves of any make or brand. In the tight confines of the pipe gallery, it is a compact solution with high torque output and adjustable travel stops to ensure that the valve is fully closed.
Result
“The new actuators have greatly increased reliability and reduced maintenance costs,” says Brian Hapke, supervisor at City of Norman Water Treatment. There were also significant savings in not replacing the valve and not having to remove if from the pipe. 214/343-9980; www.ktork.com.
Vibration analyzer reveals loose bolts and bearings on pump station
Problem
The water treatment facility in Fairfield, Ohio, uses vibration analysis as part of a condition monitoring planned/predictive maintenance program. Vibration analysis identified “severe mechanical looseness” on a pumping station pump.
Solution
Initial baseline measurements revealed the mechanical looseness and a possible coupling problem with the pump and motor assembly. The vibration data collected with the VIXPERT 2-channel vibration analyzer and later plotted with the OMNITREND software from LUDECA showed severe impacting with high-frequency harmonics characteristic of looseness in both pump bearings. Utility personnel believed the looseness could be related to loose bolts on the bearing mounts and flanges or, in a worst-case scenario, internal looseness of the bearing components themselves.
Result
Inspection found that most of the mounting bolts associated with the pump-bearing flange and pump supports were very loose. Inspection of the motor-pump shaft coupling also revealed a lack of proper lubrication around the steel grid component. After repairs consisting of tightening flange-mounting bolts and pump support bolts, follow-up vibration measurements verified satisfactory results. 305/591-8935; www.ludeca.com.
New pumps upgrade obsolete water system
Problem
The obsolete water system of Higuey, Dominican Republic, was not able to pump enough clean water to meet the demands for a population of 100,000 people.
Solution
Four National Pump Company 200 hp M14HC three-stage raw water pumps, each with 2,000 gpm capacity, were installed at a river pump station. From there, the raw water is pumped to the treatment plant, which has been upgraded with two National Pump Company 75 hp H24LC single-stage backwash pumps (capacity 4,000 gpm) and four 400 hp H14XHC four-stage high-service pumps (capacity 4,000 gpm) to transport treated water to the holding tanks.
Result
A total of 10 pumps were installed to modernize the water system and deliver water successfully to the people of Higuey. 800/966-5240; www.nationalpumpcompany.com.
Hose pump helps plant reach its potential
Problem
Madison County Water, a 10 mgd water plant in rural Alabama, utilized traditional diaphragm-style metering pumps to chemically dose reservoir water with sodium hypochlorite prior to distribution. Over time, the diaphragm pumps lost the ability to self-prime, and when the sodium hypochlorite tank level dropped below 5 feet, the pumps did not operate. However, because there are no flowmeters, it took two hours or more for the problem to show up in residual analysis. Due to this suction efficiency problem, the plant decided it was time for a change.
Solution
The plant decided on a Verderflex Dura 10 hose pump from Verder. It is capable of pulling suction lift up to 31 feet of liquid, which was more than ample to drain the sodium hypochlorite tank entirely. The installation was able to reuse the mounting shelf, platform, all suction and discharge piping and appurtenances like gauges and valves. They were also able to reuse the motor and VFD as well.
Result
The plant not only saved equipment cost, but because the pump was now able to empty the tank entirely, the frequency of sodium hypochlorite deliveries was also substantially reduced. 877/783-7337; www.verder-us.com.