Four-way reversal valve for pipe cleaning devices - incorporates control piston guided in control sleeve

摘要

The four way reversal valve for a pipe cleaning device includes a control piston (16) mounted in the valve housing and longitudinally displaceable between two working positions. The control piston is guided in a control sleeve (11). At each end of the control piston there is an operating piston (29, 30) which is longitudinally displaceable in the valve housing. The dia. of the operating piston (29, 30) is substantially greater than the dia. of the control piston (16), pref. twice as big. USE/ADVANTAGE - The switch over takes place as the control piston is displaced owing to a large build-up of pressure.