上海胡桥公社机修厂所生产的H747—L型真空连续熬糖设备配备水环式真空泵。经过长期观察,这种水环式真空泵效果不理想。例如:宝鸡副食品加工厂的真空连续熬糖设备采用水环式真空泵,两台同时使用,其真空度才达760mm汞柱。而西安糖果厂、西安制糖厂、西安食品厂的水环式真空泵,其真空度均为610mm—640mm汞柱,达不到 The H747-L type vacuum continuous boil-sugar equipment produced by Shanghai Huqiao Commune Machine Factory is equipped with a water ring vacuum pump. After long-term observation, this water ring vacuum pump effect is not satisfactory. For example: Baoji non-staple food processing plant vacuum continuous boil sugar water ring vacuum pump, two at the same time, the vacuum reached 760mm Hg. The Xi’an sugar factory, Xi’an sugar factory, Xi’an Food Factory water ring vacuum pump, the vacuum are 610mm-640mm Hg, less than