The control device for a fluid flow rate comprises a body defining at least one first chamber housing a piston and connected to the outside via fluid transfer conduits. The body comprises a first portion connectable to a delivery line for said fluid and provided with first transfer conduits connectable to the delivery line for the fluid, and a second portion removably connected to the first portion. The second portion defines the first chambers connected to second transfer conduits, themselves connected to the first transfer conduits.