Can someone explain to me what lead and lag time are? Also, what are the three flow characteristics? Linear, equal percentage but what is the third. If I wanted to have a minimum stop at 25% on a non-linear valve such as a butterfly valve, how would I achieve this. Obviously you cannot just restrict the valve by 25% of its travel as it is not linear
Hope this helps in some way... To start the 3 main flow characteristics of a control valve are Liner, Equal percentage and Quick opening (or fast opening). If you interested there are also other characteristics. As far as i am aware the lead time is the time in which a signal is sent to the valve and the lag time is the time in which the actuator moves and closes the valve. The pysical movement. As for your final question the only thing i can think of is to alter the actual size of the butterfly valve or put a reducer before it. Sorry if my information was of little use.
