Fire pump operational principle

When the pump is working, first close discharge valve of the pump and make the pump start through prime mover. Meanwhile water-ring vacuum pump works through belt pulley. After the air in suction pipeline turns into vacuum, water floods into the pump. Due to the rotary effort of impeller, water in the pump produces water pressure. This pressure acts on the primer separated valve. Then primer separated valve lets belt break away. After the water-ring primer pump stops working, open discharge valve, and the pump will work.