S. SH middle-open type centrifugal pump; SZ water-ring vacuum pump; SPB spurt; IS rinsing centrifugal pump; IR hot water pump; NIB bump; DG water supply pump for boiler; XBD. horizontal multi-stage fire-fighting pump; GC water supply pump for boiler; IS chemical centrifugal pumps; DL multistage vertical centrifugal pump; W vortex pump; R hot-water circulating pump; IY. ISY transfer pump; IQ series centrifugal water pump; ZX self-suction water pump; G single-screw pump; DF