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Training & Development
YANBU ARAMCO SINOPEC REFINING COMPANY
(YASREF) Ltd.
Control Valves
Mohamed Ibrahim
Objectives
• By the end of this training you should :-
- - Define control valve .
- - Be aware about control valve types.
- - Be aware about control valve internal
components.
- - know control valve accessories.
- - Be aware about the problems that impact
control valve.
About Instrumentation
controlvalve is simply a variable orifice that is used to regulate the flow
of a process fluid according to the requirementsof the process.
Control valves types
CONTROL VALVES TYPES
Ball Valve Globe Valve
Butterfly Valve Gate Valve
Plug Valve
Needle Valve
pinch Valve
Diaphragm Valve
Air to open Air to close
Valve Body Assembly
Valve Body Assembly – Components Names
• Video & Coffee break ???
Extension Bonnet: A bonnet with greater
dimension between the packing box and
bonnet flange for hot or cold service.
• Valve Bonnet
Extension Bonnet
Control Valve Actuators & Accessories
Three common types of actuators used :
1- pneumatic actuators (Diaphragms & Pistons).
2- Electric actuators.
3- Hydraulicactuators
Control valve actuators translate a control signal (normally 3-to-15 psi or
4-to-20 mA) into the large force or torque that is needed to manipulate a
valve.
Diaphragm Actuator
Piston Actuator
Hydraulic Actuator
Electrical Actuator
• Solenoid Valve is electrical actuated valve categorizedto three types:
• 1- Direct acting .
• 2- Manual reset .
• 3- Pilot operated .
Manual Reset
SOLENOID VALVE
Pilot operated solenoid used to switch the flow of air
Direct acting simple ON/OFF Operation
Pressure regulators
A pressure regulator is an adjustable valve
that is designed to automatically control the
pressure downstream of the regulator.
Positioners
A positioner is a device used to ensure positive
position of a valve or damper actuator.
All positioners have a feedback link from
the valve shaft, providing accurate valve
position information. Positioners can work
with linear or rotary actuation and can be
used to increase the actuation power
Linear positioner
Rotary positioner
Cavitation is a condition that occurs in liquid flow where the internal pressureof the liquid at some
point falls below the vaporpressureand vapor bubbles form and at some other point downstream
rises above the vaporpressureagain. As this pressurerecovers so that the bubbles collapse, and
cavitation takes place.
Flashing is a condition that occurs with liquid flow where the pressurefalls below the vapor
pressureand remains below it. There are then two phases flowing (i.e. liquid and vapor)downstream.
Severe damage can occur inside a valve due to erosion caused by the impact of liquid droplets traveling
at high speeds
QUESTIONS
Any Questions???
Thanks???

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YASREF Control Valves Training

  • 1. Training & Development YANBU ARAMCO SINOPEC REFINING COMPANY (YASREF) Ltd. Control Valves Mohamed Ibrahim
  • 2. Objectives • By the end of this training you should :- - - Define control valve . - - Be aware about control valve types. - - Be aware about control valve internal components. - - know control valve accessories. - - Be aware about the problems that impact control valve.
  • 4. controlvalve is simply a variable orifice that is used to regulate the flow of a process fluid according to the requirementsof the process.
  • 6.
  • 7. Ball Valve Globe Valve Butterfly Valve Gate Valve Plug Valve Needle Valve pinch Valve Diaphragm Valve
  • 8.
  • 9. Air to open Air to close
  • 11. Valve Body Assembly – Components Names
  • 12.
  • 13.
  • 14. • Video & Coffee break ???
  • 15. Extension Bonnet: A bonnet with greater dimension between the packing box and bonnet flange for hot or cold service. • Valve Bonnet Extension Bonnet
  • 16. Control Valve Actuators & Accessories Three common types of actuators used : 1- pneumatic actuators (Diaphragms & Pistons). 2- Electric actuators. 3- Hydraulicactuators Control valve actuators translate a control signal (normally 3-to-15 psi or 4-to-20 mA) into the large force or torque that is needed to manipulate a valve. Diaphragm Actuator Piston Actuator Hydraulic Actuator Electrical Actuator
  • 17. • Solenoid Valve is electrical actuated valve categorizedto three types: • 1- Direct acting . • 2- Manual reset . • 3- Pilot operated . Manual Reset SOLENOID VALVE Pilot operated solenoid used to switch the flow of air Direct acting simple ON/OFF Operation
  • 18. Pressure regulators A pressure regulator is an adjustable valve that is designed to automatically control the pressure downstream of the regulator.
  • 19. Positioners A positioner is a device used to ensure positive position of a valve or damper actuator. All positioners have a feedback link from the valve shaft, providing accurate valve position information. Positioners can work with linear or rotary actuation and can be used to increase the actuation power Linear positioner Rotary positioner
  • 20. Cavitation is a condition that occurs in liquid flow where the internal pressureof the liquid at some point falls below the vaporpressureand vapor bubbles form and at some other point downstream rises above the vaporpressureagain. As this pressurerecovers so that the bubbles collapse, and cavitation takes place. Flashing is a condition that occurs with liquid flow where the pressurefalls below the vapor pressureand remains below it. There are then two phases flowing (i.e. liquid and vapor)downstream. Severe damage can occur inside a valve due to erosion caused by the impact of liquid droplets traveling at high speeds