MOTOR OPERATOR VALVES FUNCTION IN POWER PLANT AND TYPES OF MOTOR OPERATER VALVES

Motor operator valves is an important item of power plant piping systems mainly . these items are generally large site and are used for different applications in plant, such as pumps discharge or suction , steam pipe line  etc. motor operator valves are often called as on-off valves, which is operates by  motors serve the purpose of fully operating or full closing valves in pipes lines, for example cooling water lines , process pipe lines where controlling of fluid in not required , motor operator valves can be used to full open allow or full stop the fluid flow, these valves are not used for throttling purpose as they serve mainly ON or OFF service application.

Motor operator valves can be of various types example - gate, ball,butterfly valves with actuator control , design of motor and valves can be different , an electronic motor is mounted on the motor operates the valve will open or close . for this motor operating valves, motor  operator with actuator control from local panel or from control room is required, there is requirement of co-ordination among piping  electrical or instrumentation process engineers for design and procurement of such motor operator valves

Applications of motor operator valves :

• when ever frequent operation is required

• valves located in remote in accessible or hazardous motorized control valves / motor operated valves are usually for full open and full close application however there are place when they are used for position control as well

Types of motor operator valves :

Motorized control valves can be classified into three types :

• Open / close valves :  Used to automate manual open and closed valves some example given below                                                                                                                Examples :
  1. Pump discharge and suction valves, 
  2. Boiler feed water isolation valve,
  3. Drum vent valves 
  4. Process steam line valves 

•  Inching valves : Used were some degree of control , gradual opening and closing is required application example.

1. Re-flux lines
2. Boiler start up vent
3. Boiler IBD valves 
4. Boiler main steam valves 

•  Precision flow valves :   This is a precision inching valve the motor operates in steps configured in controller  example 10 % 15 % opening steps . in precision flow valves , a continues control is enabled by the use of proper feedback from the field to the controller which is not usually found in other motor operated valves .

  

  Open /  Close MOV

  
  

  

  Inching valve

  
  

  
  

  
  

  
  

  
  

  
  

  
  

  
  

  
  

  
  

  Motor operating valve assembling and operation animation video :