... standard JB/T6663.1-93,which mainly consist of impeller,casing,sealing,bearing body etc, apply to convey clear water or ... radius ceaselessly rising and outdistance atmosphere pressure, formed a certain suction in water inlet. Under atmosphere pressure, the lower water push ... and flowing water, drive the impeller to pump up water. The suction of the self-priming pump is not exceed one atmos, around ...