The circulating water pump is based on a multi-use vacuum pump, according to the characteristics of the laboratory smaller, one-time molding shell, reduce the volume of improvements made, with small size, light weight, appearance and other characteristics, two tables, two suction head, the same multi-sided with a vacuum pump, even if the teacher is demonstrating, students can at any side of the boot, shutdown. This product is circulating water as the working fluid, the use of a negative pressure jet principle and the design of a new multi-use vacuum pump, to provide for the chemical laboratory vacuum conditions, and can provide circulating cooling water to the reaction apparatus is widely used in evaporation, distillation, crystallization, filtration, sublimation and other operations. is the ideal device universities, chemicals, food processing and other areas of the laboratory.