Abstract: Disclosed is a rotary valve 1 comprising a stator 20 and a rotor 40 generally in rotary sliding engagement with the said stator about a valve axis RA, the stator including a plurality of fluid ports 22, 26, 28, the rotor 40 being operable to selectively fluidically interconnect two or more of said ports during its rotary sliding engagement. The valve further includes an actuator (70) for disengagement of the rotor from the stator to enable efficient cleaning of the valve interconnections.

Abstract: A rotary selection valve (1) is disclosed having a stator (20) and a rotor (40) having complementary abutting fluid tight surfaces (30,50) for relative rotation between the stator (20) and the rotor (40) about a rotational axis. The stator or rotor has at least one connection port in fluid communication with an associated orifice at said stator or rotor abutment surfaces (30,50). The stator and/or rotor further comprise a separate fluid recess extending radially beyond said associated orifice or orifices and open to the complementary abutment surfaces for improving the automatic cleaning of the valve.

Abstract: The invention relates to a chromatography pump, comprising a cylinder (202, 402) in which a piston (204, 404) is arranged for a reciprocating movement; a front element (208) provided with a cylinder head area (210) which together with the cylinder (202, 402) and the piston (204, 404) defines a cylinder space (212); an inlet valve (214) and an outlet valve (216) arranged in the front element (208); an inlet channel (218) arranged in the front element (208) between the inlet valve (214) and the cylinder head area (210); an outlet channel (220) arranged in the front element (208) between the cylinder head area (210) and the outlet valve (216). The inlet channel (218) and outlet channel (220) extend in a substantially straight direction, so that air bubbles (234) are prevented from being trapped within the inlet and outlet channels (218, 220).