Centrifugal pump suction tube flanged to the front of the impeller inlet is called the suction chamber. Its effect is to guide the liquid to flow smoothly into the impeller in the lowest hydraulic loss, and to distribute the flow rate as evenly as possible in the inlet of the impeller. The suction chamber can be divided into straight tapered suction chamber, bending tube suction chamber, circular suction chamber and semi-spiral suction chamber.

Straight conical suction chamber: this type of suction chamber is of good hydraulic performance, simple structure and convenient manufacturing. The fluid is flowing in the straight conical shape and the velocity increases, and the velocity distribution tends to be more uniform. The cone suction chamber is about 70-80. This type of suction chamber is widely used in single-stage cantilevered centrifugal pumps.