b An actuator has a stem movement which at full travel is 40

b) An actuator has a stem movement which at full travel is 40 mm. It is mounted with a linear plug process control valve which has a minimum flow rate of 0 and a maximum flow rate of 0.20m3/s. What will be the flow rate when the stem movement is 25mm? [5 marks] c) Design a cam follower system to give constant follower speeds over follower displacements varying from 60 to 120 mm. [5 marks]

Solution

b)

A percentage stem displacement of (25/40)*100=62.5% gives a percentage flow rate of 62.5% i.e. 0.2*0.625=0.125m3/s.