Control Valve and Positioner

Dear All,

Please answer the following.

1.) What will happen if Positioner feed back link fail or broke? What will be the state of Control Valve?

2.) How we can use a 30° Positioner to rotate a ball or butterfly valve 90°. What types of changes we have to do on C.V. steam.

3.) How to generate a RFQ of Control Valve and Positioner?

4.) How you can replace Pneumatic Positioner with Electronic Positioner?

5.) Define types of Control Valve with respect to Action, Moment, Valves and there opening?

Regard's

Adeeb