Vane vs volumetric pump - is there a difference?

[sheygetz]

I've noticed several websites by dealers selling Astoria macchinas differentiate between vane pump (on the Divina line) and volumetric pump (on the Argentas). I would have thought both were rotary, i.e. not vibe, pumps -- am I missing any subtle differences here?

sheygetz

[terryz]

I think it is simply a difference in terminology. Rotary vane pumps are standard on all Astoria machines with the exception of the CK and CKXE which have the rotary available as an option.