Köly PVC-U ball valves, pneumatic
Ball valves and shut-off valves
Ball valves in PVC-U carrying a mounted pneumatic rotary actuator shut off or release lines carrying water, alkaline solutions, acids, plus other media compatible to plastics, at a nominal pressure of PN 16 bar. Ball as well as body are moulded in PVC-U, so no metal part touches the fluid. The range covers 108 versions in nominal sizes DN 20 to DN 80, the valve face to face length running from 80 to 284 mm.
Three points drive the choice: pipe connection, seal material, plus the behaviour when control air fails. Female threads suit detachable transitions, while solvent socket ends belong on permanently bonded PVC-U pipework. Seat plus stem seals come in EPDM for aqueous fluids as well as alkaline solutions, alternatively in FKM for oily, oxidising media. On the actuator side the choice runs double acting, spring to close, spring to open.
The fail safe position follows the process: spring to close shuts the line once compressed air is lost, spring to open keeps it clear, while a double acting unit holds its last commanded position only as long as control pressure stays applied. Check the face to face length of 80 to 284 mm against the existing pipe run before ordering, because spring return versions build longer than double acting ones. Solvent socket ends require a stress free layout, since the bonded joint cannot be undone after curing.
Water treatment, swimming pool systems, cooling circuits, wherever chloride bearing water attacks metal valves. In electroplating plus surface finishing the valves switch baths, rinse water, alkaline solutions. Further uses cover dosing stations, rainwater plus waste water plants, laboratory circuits, where sizes DN 20 to DN 80 meet PVC-U pipework.
