Noble Procetech Engineers One Of The Leading Manufacturers and Supplier Of Diaphragm Metering Pump in Chennai. A Diaphragm Metering Pump is a positive displacement pump designed to deliver precise volumes of liquids in controlled amounts. This pump type is widely used in applications where accurate chemical dosing is essential, such as water treatment, chemical processing, and food and beverage industries. A flexible diaphragm is driven by either mechanical or hydraulic means, displacing the liquid in controlled pulses.