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Pneumatic Actuator
Rack & pinion pneumatic actuator
Double acting pneumatic
actuator
When air pressure comes into port A to the middle chamber,
the piston move aside. The air from the side chambers will comes
out from Port B
When air pressure comes into port B to
the side chambers, the piston move back to
the previous position. The air from the
middle chamber will comes out from Port A
Rack & pinion pneumatic actuator
Single acting pneumatic
actuator
When air pressure comes into port A into the middle chamber,
the piston move aside pushing the springs.
The air from the spring chambers will comes
out to the atmosphere.
When air pressure is released out (exhaust)
from port A , the springs will push the piston back into the previous position.
The air from the side chambers will comes
in from the atmosphere into the
spring chambers.
Rack & pinion pneumatic actuator
Scotch Yoke pneumatic actuator
Scotch Yoke pneumatic actuator
CAM
Side Bar
BIG Scotch Yoke pneumatic actuator
BIG Scotch Yoke pneumatic actuator
CAM
Side Bar
BIG Scotch Yoke pneumatic actuator
Rotary Vane pneumatic actuator
4-piston rack & pinion pneumatic actuator
Our Habonim 4-piston rack & pinion pneumatic actuator is unique compared with the traditional
2-piston rack & pinion pneumatic actuator
Video
Pneumatic actuator
Double acting close Double acting open
Single acting close Single acting open
Springs
Springs
Limitation of Habonim pneumatic actuator
Habonim pneumatic actuator is limited to be installed up to 8” size of ball valve # 150 only
ISO-5211 mounting
Pneumatic actuator bottom plane has a standard ISO-5211 mounting dimension to match with the ISO-5211 mounting pad on top of a ball valve construction
ISO mounting pad ISO mounting pad
ISO mounting pad
ISO-5211 mounting
Mounting bracket-Adapter
• Rigid construction • Dual ISO pattern mounting planes • High visibility of stem packing • Aesthetic looks • Easy of access for assembly tools • Stainless steel CF8 material • Holes for limit switches • Holes for locking pins MK47C-XX-CYY
Valve torque table
For example 2” Habonim ball valve (with TFM seat material) • If the fluid pressure = 10 bar The torque of the ball valve = 29 NM (blue color) With 20 % safety factor The torque of the ball valve = 34.8 bar (green color) • The red color line is 316 SS stem operating torque limit = 48.6 NM • The 17-4 PH stem operating torque limit = 268 NM
Stem operating torque limit (MAST)
• If a ball valve is operated manually the manual turning torque of an operator is limited the operator manual turning torque cannot damage the ball valve’s stem easily !
• But if a ball valve is operated by a pneumatic actuator we cannot control the turning torque of the actuator especially if we over sized the actuator model could be the turning torque is much bigger than the 316SS stem operating torque limit it can damage the stem in this case we have to use a better material for stem 17-4 PH material is harder & tougher than 316 SS material
Valve Stem
Basic actuator definitions
Ball valve torque
BALL VALVE TORQUE: BTO (break torque to open) = 100 %
RTO (run torque to open) = 30 % ETO (end torque to open) = 50 %
BTO (break torque to close) = 55 % RTO (run torque to close) = 30 % ETO (end torque to close) = 50 %
Habonim 2” size torque (after 20 % safety factor) BTO (break torque to open) = 34.8 NM
RTO (run torque to open) = (0.3 x 34.8 NM) ETO (end torque to open) = (0.5 x 34.8 NM)
BTO (break torque to close) = (0.55 x 34.8 NM) RTO (run torque to close) = (0.3 x 34.8 NM) ETO (end torque to close) = (0.5 x 34.8 NM)
Habonim double acting actuator chart
NM
Sizing double acting pneumatic actuator
2” ball valve with TFM seat After 20 % safety factor Torque = 34.8 NM Pneumatic actuator sizing: With 5 bar air pressure Model C-25 pneumatic actuator is choosen Actuator torque @ 5 bar air pressure = 65 NM Check the stem MAST 316 SS material stem MAST = only 48.6 NM < 65 NM actuator torque Have to use 17-4 PH stem material with 268NM of MAST
Habonim single acting actuator chart for normally closed ball valve
NM
Sizing single acting pneumatic actuator (normally closed)
2” ball valve with TFM seat After 20 % safety factor Torque = 34.8 NM Pneumatic actuator sizing: With 5 bar air pressure Model C30-2B is choosen Spring end torque = 36 NM > 34.8 NM Actuator air start torque = 70 NM Check the stem MAST 316 SS material stem MAST = only 48.6 NM < 70 NM actuator torque Have to use 17-4 PH stem material with 268 NM of MAST
Habonim single acting actuator chart
NM
Sizing single acting pneumatic actuator (normally open)
2” ball valve with TFM seat After 20 % safety factor Torque = 34.8 NM Pneumatic actuator sizing: With 5 bar air pressure Model C25-2B is choosen first Spring start torque = 36 NM > 34.8 NM But actuator air end torque = only 27 NM CANNOT BE USED ! Model C30-2B is choosen next Spring start torque = 62 NM > 34.8 NM Actuator air end torque = 43 NM CAN BE USED ! Check the stem MAST 316 SS material stem MAST = only 48.6 NM > 43 NM actuator torque No need to change the stem material !
Combination Habonim ball valve + Actuator
Impact torque booster
Impact torque booster
Impact torque booster
Impact torque booster
Impact torque booster
Impact torque booster
Sizing Impact torque booster
Sizing Impact torque booster
Type of Automatic valves
Automatic On-Off valve Automatic On-Off valve
Piston actuator
Angle seat piston valve
How angle seat piston valve works
When the 3-way solenoid valve is not yet working No air pressure is coming into the piston actuator of the angle seat piston valve
valve closes
When the 3-way solenoid valve is energized Air pressure is coming into the piston actuator of the angle seat piston valve
valve open
Exhaust Air Supply Air Supply
Automatic On-Off valve
Solenoid valve for hazardous area
Oil & Gas area does not allow Namur solenoid valve installed in a pneumatic actuator !
Solenoid valve must be connected with instrument tubing & fitting !
Principle of flow switch Principle of level switch
Principle of pressure switch Principle of temperature switch
Principle of On-Off control
Principle of On-Off control
Pressure Switch
Temperature Switch
Level Switch
Flow Switch
• Wiring is also shorter
Silencer
Silencer is used to absorb the pneumatic/air noise at the exhaust port
of a solenoid valve
Silencer + Speed Controller
Combination silencer w/ speed controller is used to absorb the pneumatic/air noise at the exhaust port of a solenoid valve.
The speed controller can be used to slow down the speed of the pneumatic actuator’s opening or closing
Quick exhaust valve
Air filter Regulator + gauge
Air filter regulator + gauge is used to reduce the air pressure coming to the
pneumatic actuator
Automatic modulating valve
Pneumatic Actuator
Positioner
Positioner
BALL VALVE
Principle of modulating control
Pressure application Temperature application
Level application Flow application
Principle of modulating control
Pressure transmitter Temperature transmitter Level transmitter Flow transmitter
Modulating controller PLC Programmable Logic Controller
DCS Distributed Control System
Principle of modulating control
Pressure application Temperature application
Level application Flow application
Why do we need positioner ?
At factory, the control ball valve is set without any fluid flowing through the control valve, we call this bench setting. The co-relationship between air supply pressure & the % of ball valve opening is represented with the “BLUE” line in the above chart When the fluid is introduced into the control ball valve a normally closed control ball valve’s co-relationship between air supply pressure & the % of valve opening will be shifted as shown in the above chart with “RED” line (the ball control valve will receive additional force to open the ball valve from the fluid flow pressure)
Why do we need positioner ?
At factory, the control ball valve is set without any flow through the control ball valve, we call this bench setting. The co-relationship between air supply pressure & the % of valve opening is represented with the “BLUE” line in the above chart When the liquid is introduced into the control ball valve a normally open control ball valve’s co-relationship between air supply pressure & the % of ball valve opening will be shifted as shown in the above chart with “RED” line (the ball control valve will receive additional force to close the ball valve from the fluid flow pressure)
Why do we need positioner ? For many applications, the air pressure coming into the
pneumatic actuator may not be enough to cope with friction and high differential pressures. A higher control pressure and stronger springs could be used, but the practical solution is to use a Positioner.
Positioner is an additional item which is usually fitted to the stem/shaft of the pneumatic actuator in order to monitor the valve position. It requires its own higher-pressure air supply, which it uses to position the valve. A valve positioner relates the input signal and the valve
position, and will provide any output pressure to the actuator to satisfy this relationship, according to the requirements of the valve, and within the limitations of the maximum supply pressure.
A positioner translates the input signal received from a controller to a required valve’s position & supplies the valve’s actuator with the required air pressure to move the valve into the correct position
A positioner ensures that there is a linear relationship between the signal input pressure from the control system and the position of the control valve. This means, that for a given input signal, the valve will always attempt to maintain the same position regardless of changes in valve differential pressure, stem friction, diaphragm hysteresis and so on.
A valve positioner relates the input signal and the valve position, and will provide any output pressure to the actuator to satisfy this relationship, according to the requirements of the valve, and within the limitations of the maximum supply pressure
Why do we need positioner ?