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    Developing Pump Performance Curves

    Hi Folks; I am developing a series of pump performance curves for pulp slurries. I am running a closed-loop Lab-Scale pipeline facility. My question is about measuring head vs. flow rate at constant RPMs. I did it for pure water by continuously feeding the system with water, and gradually...
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    Problem with pressure drop in pipeline

    Hi Folks; As we all knew, and I used to experimentally observe it, as the temperature of water increases, pressure drop through pipeline (kPa/m) decreases. Now, I am getting the opposite, while the results are so consistent and reproducible !!! As the water temperature increases, pressure...
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    Velocity Variation through Pipeline

    Hi Imagine there is a closed-loop pipeline which we are pumping pure water. Reasonably, we expect the pressure-drop to increase towards the end, due to friction and minor losses. My question, however, is about the velocity. When you half the length of the loop, at the same pump power...
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    A Problem with the Pump

    The discharge pressure is a few cm ahead of discharge valve ! The loop is all horizontal !
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    A Problem with the Pump

    Also I changed the suction hose !
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    A Problem with the Pump

    Today I spent $4000 to change all the pump impeller and plates and sealings and orings and ... But the problem is still there !!! OMG ! I am getting crazy ! I can make the same velocity, but not the same pressure !!! Even for pure water ! I am now in a real trouble ! I cant make any more guess ...
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    A Problem with the Pump

    Sure not ! I've check step by step all the line. it is completely clean and transducer's are also fine; no clogging ! Within 1 week, pressures suddenly dropped ! While the velocities are still the same. It is obviously violating Bernuli's law !!!
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    A Problem with the Pump

    Hi Folks; I am facing a problem with a real experimental pumping case. I am running a schedule 40, commercial steel, 45m length, 2" diameter pipeline for water. Since past month, suddenly, the head of the pumped dropped by 0.3 Kpa/m, however, the velocities are the same. I wonder is it...