In this process, two chemical streams are mixed together in a reactor vessel. The ensuing chemical reaction is exothermic (heat-producing) and must be cooled by a water cooling system to prevent overheating of the vessel and piping. A temperature transmitter (TT) senses the reaction product temperature and sends a 4-20 mA signal to a temperature indicating controller (TIC). The controller then sends a 4-20 mA control signal to the temperature valve (TV) to throttle cooling water flow:
Suppose something fails in the control valve mechanism to make it incapable of opening further than 80%. From 0% to 80% position, however, the valve responds normally.
Describe in detail the effect this fault will have on the performance of the cooling system.
Answer :
There will be no effect on the performance of this cooling system, except in circumstances where the controller tries to open the valve further than 80%. In those cases, the process temperature will exceed setpoint.
Share Your Answers via Comments