水封式真空泵浦配備有偏置葉輪。水封式由在泵殼內同心旋轉的工作液（通常是水）形成。工業廢氣通過吸入口進入，在葉輪片之間傳送，壓縮之後通過排氣口排出，還會伴隨一些工作液。真空泵浦可採用水迴圈的開環或閉環進行操作。
Dolphin
Busch Launches New Series of Dolphin Liquid Ring Vacuum Pumps
Busch Vacuum Pumps and Systems has now launched an entirely new series of liquid ring vacuum pumps. The new Dolphin LM/LT vacuum pumps have been completely redesigned but are based on proven liquid...