Savings Calculator for Centrifugal Pumps

Centrifugal pumps are one of the major energy consuming end-devices in developed coun-tries both in industrial and services sectors. According to recent studies, even 30 % of the energy used in pumping systems could be saved by more careful choosing of devices and system design. One of the most efficient and affordable ways to decrease the energy con-sumption of the pumping system is to substitute traditionally used flow control methods, like valve control, with modern variable speed drive (VSD) control. In this thesis, Microsoft Excel based program, Savings Calculator for Centrifugal Pumps (SCCP), is designed. SCCP calculates the achievable energy and financial savings when throttle control is substituted by VSD control in the pumping system. Compared to the sim-ilar existing programs, the goal is to make SCCP calculations more accurate and require less input information. Also some useful additional features are added to the designed program to make it more user friendly. The reliability of the calculations of designed program seem to vary depending on case. The results are corresponding accurately to the laboratory measurements, but there occurs high deviations in some cases, when the results are compared to the pump information specified by manufacturer. On the basis of verification in this thesis, SCCP seems to be at least as accurate as similar existing programs and it can be used as help in investment decision whether to have VSD or not.

Pelton centrifugal pumps.

Mode of access: Internet.

Investigation of centrifugal pumps : Part II, Experiments with a six inch horizontal centrifugal pump, comparing the efficiency of circular and spiral cases and showing the effect of air leakage

Mode of access: Internet.

Monitoring of centrifugal pump operation by a frequency converter

Centrifugal pumps are widely used in industrial and municipal applications, and they are an important end-use application of electric energy. However, in many cases centrifugal pumps operate with a significantly lower energy efficiency than they actually could, which typically has an increasing effect on the pump energy consumption and the resulting energy costs. Typical reasons for this are the incorrect dimensioning of the pumping system components and inefficiency of the applied pump control method. Besides the increase in energy costs, an inefficient operation may increase the risk of a pump failure and thereby the maintenance costs. In the worst case, a pump failure may lead to a process shutdown accruing additional costs. Nowadays, centrifugal pumps are often controlled by adjusting their rotational speed, which affects the resulting flow rate and output pressure of the pumped fluid. Typically, the speed control is realised with a frequency converter that allows the control of the rotational speed of an induction motor. Since a frequency converter can estimate the motor rotational speed and shaft torque without external measurement sensors on the motor shaft, it also allows the development and use of sensorless methods for the estimation of the pump operation. Still today, the monitoring of pump operation is based on additional measurements and visual check-ups, which may not be applicable to determine the energy efficiency of the pump operation. This doctoral thesis concentrates on the methods that allow the use of a frequency converter as a monitoring and analysis device for a centrifugal pump. Firstly, the determination of energy-efficiency- and reliability-based limits for the recommendable operating region of a variable-speed-driven centrifugal pump is discussed with a case study for the laboratory pumping system. Then, three model-based estimation methods for the pump operating location are studied, and their accuracy is determined by laboratory tests. In addition, a novel method to detect the occurrence of cavitation or flow recirculation in a centrifugal pump by a frequency converter is introduced. Its sensitivity compared with known cavitation detection methods is evaluated, and its applicability is verified by laboratory measurements for three different pumps and by using two different frequency converters. The main focus of this thesis is on the radial flow end-suction centrifugal pumps, but the studied methods can also be feasible with mixed and axial flow centrifugal pumps, if allowed by their characteristics.

Energy Efficiency of Pumping Medium Consistency Pulp with Centrifugal Pump

Approximately a quarter of electrical power consumption in pulp and paper industry is used in different pumping systems. Therefore, improving pumping system efficiency is a considerable way to reduce energy consumption in different processes. Pumping of wood pulp in different consistencies is common in pulp and paper industry. Earlier, centrifugal pumps were used to pump pulp only at low consistencies, but development of MC technology has made it possible to pump medium consistency pulp. Pulp is a non-Newtonian fluid, which flow characteristics are significantly different than what of water. In this thesis is examined the energy efficiency of pumping medium consistency pulp with centrifugal pump. The factors effecting the pumping of MC pulp are presented and through case study is examined the energy efficiency of pumping in practice. With data obtained from the case study are evaluated the effects of pump rotational speed and pulp consistency on energy efficiency. Additionally, losses caused by control valve and validity of affinity laws in pulp pumping are evaluated. The results of this study can be used for demonstrating the energy consumption of MC pumping processes and finding ways to improve energy efficiency in these processes.

Automatic system identification and optimization of centrifugal pump operation

Centrifugal pumps are a notable end-consumer of electrical energy. Typical application of a centrifugal pump is the filling or emptying of a reservoir tank, where the pump is often operated at a constant speed until the process is completed. Installing a frequency converter to control the motor substitutes the traditional fixed-speed pumping system, allows the optimization of rotational speed profile for the pumping tasks and enables the estimation of rotational speed and shaft torque of an induction motor without any additional measurements from the motor shaft. Utilization of variable-speed operation provides the possibility to decrease the overall energy consumption of the pumping task. The static head of the pumping process may change during the pumping task. In such systems, the minimum rotational speed changes during reservoir filling or emptying, and the minimum energy consumption can’t be achieved with a fixed rotational speed. This thesis presents embedded algorithms to automatically identify, optimize and monitor pumping processes between supply and destination reservoirs, and evaluates the changing static head –based optimization method.

Operator, organizational, field and depot maintenance manual : pump, centrifugal, petroleum, gasoline driven, trailer MTD, 4 in., 350 GPM, 275 ft head (Gorman-Rupp model 04A12-MVG4D), FSN 4320-691-1071.

"March 1961."

Organizational, DS, GS, and depot maintenance manual : pump, centrifugal, gasoline driven, skid mounted, 6-inch, 1120 GPM, self-priming (Carver model K906EWA), FSN 4320-968-6264.

"February 1966."

Operator, organizational, direct support, and general support maintenance manual including repair parts and special tools lists for pump, centrifugal, water, 200 gpm (Gorman-Rupp Co, model 62-1/2E13-4A084), FSN 4320-935-1618.

"June 1969."

Operator, organizational, field, and depot maintenance manual : pump, centrifugal, gasoline driven, base mtd, 2 in., 166 gpm, 25 ft head (Barnes model 10-MG) serial number 1 through 207, FSN 4320-820-0700.

Includes index.

Operator, organizational, direct and general suport, and depot maintenance manual : pump, centrifugal, gasoline engine driven, 50 GPM, 100-foot head, flammable liquid, bulk transfer (Barnes model-QM-2-28002) FSN 4320-913-7131.

Includes index.

Operator and organizational maintenance manual : pump, centrifugal, fresh water; gasoline driven, 2 wheel mounted; 4 in 500 GPM, 30 ft head, (Carver model K400S) FSN 4320-810-7311 (less engine).

Includes index.g

Organizational, direct and general support, and depot maintenance repair parts and special tools list : pump, centrifugal, GED, skid mounted, 6 in., 1120 gpm (Carver model K906MP), FSN 4320-929-0681.

"October 1968."

Operator and organizational maintenance manual : pump, centrifugal, fresh water; gasoline driven, 2 wheel mounted; 4 in 500 gpm, 30 ft head, (Carver model K400S) FSN 4320-810-7311 (less engine).

"March 1961."

Operator, organizational, field, and depot maintenance manual : pump, centrifugal, fresh water, gasoline driven, base mounted, 4 in, 200 gpm, 300 ft head (Carver model 4WHIS), serial number range 37715RF through 37814RF, FSN 4320-810-7310 ....

"September 1961."