Double-casing volute vertically suspended pumps are referred to as pump type VS7.
Double-casing diffuser vertically suspended pumps are referred to as VS 6 type pumps.
Vertically suspended cantilever sump pumps shall be designated pump type VS5.
Vertically suspended, single-casing volute line-shaft driven sump pumps are referred to as VS 4 type pumps.
Wet pit, vertically suspended, single-casing axial-flow pumps with discharge through the column shall are referred to as pump type VS3.
Wet pit, vertically suspended single-casing volute pumps with discharge through the column are referred to as pump type VS2.
Wet pit, vertically suspended, single-casing diffuser pumps with discharge through the column are referred to as pump type VS1.