A flow rate selection valve includes a gate cylinder having a gate
cylinder rotational axis and having at least two flow rate determining
passageways and passing laterally through the gate cylinder at
orientations angularly displaced from each other and having cylinder
rotation structure; and a valve housing containing a flow passageway and
having a cylinder receiving bore intersecting the flow passageway into
which the gate cylinder is rotatably and sealingly mounted, the gate
cylinder dividing the flow passageway into a passageway inlet end and a
passageway outlet end, the flow passageway containing a passageway
registration barrier extending across the flow passageway and sealingly
abutting the gate cylinder and having several flow ports with different
minimum diameters, each flow port positioned to register with one of the
flow rate determining passageway.