A system and method for measuring pressure and flow rate of polymer slurry circulating in a loop reactor. For flow rate measurement, the loop reactor has a pressure tap on an outside radius of an elbow of the loop and a pressure tap on an inside radius of the elbow. The pressure taps incorporate diaphragms. Sensing legs couple the pressure taps with a differential pressure meter configured to provide a signal indicative of the flow rate of the polymer slurry. For pressure measurement, pressure taps without diaphragms at the loop reactor wall may be disposed at various points along the loop reactor, the pressure taps coupled to pressure sensing lines. A diluent flush line having a screen disposed therein may provide diluent to the pressure taps. The screen may reduce fouling of the pressure tap and sensing line with solids from the reactor.