Plastics molding requires plastics to be heated and cooled according to specific guidelines to ensure that the finished product has all the desired qualities. Controlling the temperatures of the molten polymer, in the mold, and the cooling water and its flow rate are critical in producing the highest quality product and maximizing output. Water and temperature controllers are the best way to ensure the proper regulation of the heating and cooling process. Hydraulically operated machinery requires tower or chilled water to maintain a safe operating temperature of hydraulic fluid.