Valve automation - help needed!


I need to move a large (1300 x 400mm) horizontal butterfly valve from open to closed and back again on an 8 second cycle (i.e. open for 4 secs, closed for 4 secs). The valve is fitted with a 150mm bell crank and a push rod that needs to be connected to a valve motor of some kind. The stroke from open to closed is 200mm, but we can fit a lever arrangement at the top end of the push rod to change the stroke to whatever suits the valve motor. The force required to move the valve is quite low (easily by hand… maybe 2-3 kgs) and we need to move the valve quite quickly (say, within 1 second?). I had thought we could use simple electric solenoids but am unsure if this is really a suitable approach. The cycle will repeat continuously 24/7. Any thoughts from the experts? Thanks.