Control valve calibration and maintenance

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#controlvalve #controlvalvecalibration #controlvalveparts
CONTROL VALVE POSITIONER WORKING PRINCIPLE
A valve Positioner is a device used to increase or decrease the air load pressure driving the actuator until the valve’s stem reaches a “POSITION” balanced to the output SIGNAL from the process variable instrument controller.
Valve positioners are used on controlling valves where accurate and rapid control is required without error or hysterises.
Positioners are generally mounted on the side-yoke or top casing of the pneumatic actuator for linear sliding stem control valves, and at/near the end-of-shaft for rotary control vales. For either basic design type, “mechanical feedback linkage” connected directly to the valve’s stem provides feedback to controller. The process controller tells the positioner to “change” position; the feedback linkage reports back to the positioner confirming that a change has occurred and gives a “sense” of the magnitude of the change in position.
Principle of Operation
The Figure shows a valve positioner . The valve positioner is a force-balanced instrument, with pneumatic module installed on a double-acting actuator for air to open action. Positioning is based on a balance of two forces; one proportional to the instrument signal and the other proportional to the stem position.
A downward force is activated as the signal pressure acts upon the diaphragms in the instrument signal capsule, through the follower arm and cam, the motion of the actuator stem is transmitted to the top end of the feedback spring resulting in the varying of tension in feedback spring as stem position changes.
The system will be in equilibrium and stem will be in the position called for by the instrument signal when these opposing forces balance exactly. The balance will move up or down and by means of the spool valve, will change the output pressures and flow rate if these opposing forces are not in balance. This will lead to the piston to moving until the tension on the feedback spring opposes exactly the instrument signal pressure.
The detailed sequence of positioner operations are as follows:
An increase in the instrument signal forces the instrument signal capsule and balance beam downward.
This motion of the balance beam also pulls the pilot valve spool downward from its equilibrium position.
This opens the pilot valve ports, supplying air to port 1 and exhausting air from port 2.
This causes the actuator piston upward. Proportionally to the valve position, to counter the force generated by the instrument signal capsule, the piston continues to stroke upwards until force in the feedback spring increases sufficiently.
At this point the balance beam and spool begin to return to equilibrium position.
As the valve spool ports start to close, the air flow rate to the actuator is decreased.
The feedback spring tension force will equal the force generated in the instrument signal capsule after the piston has reached the required position.
The balance beam and instrument signal capsule will remain in their equilibrium positions with no air flowing to the actuator until a change in the instrument signal is made.
A proportional downward movement of the actuator piston and stem is affected by a decrease in the instrument signal which reverses the described actions.

[@mdmoynshakil6964]

Very helpful information But ur speaking time need to camera position on right parts....

[@azadroy477]

Thanku.. But thori cear full video baniye

[@anilkumardwivedi3694]

आपके टाइटल के अनुसार मेंटेनेंस पार्ट नहीं बताया है। बाकी calibration पार्ट अच्छा बताया है इसके लिए धन्यवाद।

[@engineeringconcepts]

Next video mai full explain karu ga

[@anilkumardwivedi3694]

@@engineeringconcepts धन्यवाद सर जी

[@sonukumarsahani8001]

Nice. And a lot of thank you sir

[@taiseenkhan9738]

Nice

[@riteshdevmurari9354]

nice information

[@engineeringconcepts]

Thanks

[@RamBabu-ev9wl]

👌

[@vishwaramtiwary81]

Very useful information bro..thank u

[@Sultankhan-pk1qh]

Thanks 😊 sir ji

[@engineeringconcepts]

Welcome dear

[@BTSI_]

sir flow serve / fisher and masonelian k positioner main manual zero and span set kerney ka ni hota hai and sir valve ko open close krna na sikhaye ... proper bench calibration ya field calibration karney btayein..

[@chhotelalprajapatiprajapat4507]

Namsty sir। Sir mujhe ye janana hai ki mere yaha Rotex cpni.ka volve hai hamara kuchh jam ho gaye Kam tarike se kam kar rahe hai to ese ham kaese thik kare

[@secretworld7938]

Sir aap xp se bta rhe h zero hoga but xp to spane ke liye h 100 %ko adjustment krne ke liye zero set krne ke liye zero adjust krege na

[@najsheikh3080]

Nice concept

[@rajasekhar-po5hs]

In our plant we use Samson posinitor for steam control. It is controlled by Yokogawa pid control output 4:20 milli amps. If the set point is 40 then it goes to 50 and then it goes down to 32 degrees. I am not changing the setting in pid. Pls explain slow operation settings tell me sir

[@ganagamvrksantosh5725]

Samson control valve positioner unable to set the position of 0-100%. In 100% setpoint it was reaching only 60%, if any adjustment was done 0% was disturbing

[@sritejajosyula]

Very well Explained Bro.

[@engineeringconcepts]

Glad you liked it

[@mdshayanahmad6838]

Value calibration mn 0%,25%,50%,75%,100%.hi dekr check kregn to valve open ho raha ya nahi.ya phir 5% 15%,30% dekr bhi check kar sakte hain.

[@BTSI_]

air to open valve

[@babykingdom6737]

Very knowledgeable video

[@engineeringconcepts]

So nice of you

[@sushantmore5926]

Sir please no send

[@engineeringconcepts]

8871004043

[@sarfrajansari166]

Sr low CV alarm kaise clear hota h

[@Tinkujia2749]

I/p ka output air pressure se itna heavy control valve open close ho jata hai ??ya external supply bhi control valve ko dete hai as a air pressure 🙏🙏 please reply, subscribed ur channel

[@engineeringconcepts]

no need for external air ۔ its operates directly I/p

[@Hindustanibaba556]

Mai service engineer k liye interview face karne ja rha hun kal . Kya kya questions kar sakta hai. Control valve me

[@azeemshaikh606]

Hello sir how to check ip transitor it's ok or not ?

[@secretworld7938]

Zero ki command pr zero position pr nhi ho rha h mera cv aur fluctuate bahaut jyada ho rha h

[@manishojha4011]

thanks sir,,,,,,

[@santoshkumardas1701]

Nice but camera bahut hila rahe the

[@ashutoshsrivastava2497]

nice concepts

[@mr.nizamulhoq851]

Hello Sir, Have a good day. I have recently facing problem in a newly buying Siemens PS2(2wire, 4-20ma, 2 wire, without HART) smart positioner connect with my existing Single acting, air to open linear actuator(pneumatic control valve) having 20mm stroke when I am going to newly calibration. During commissioning this new positioner with existing control valve/actuator in initial condition its display shows P 85 and NOINI mode, at that time when if i press (+) and (-) button then the actuator totally doesn’t not move.only small clicking sound hearing inside the positioner and little air Release from actuating pressureline(Y1) of positioner , however pneumatic(4kg air pressure) and electrical(4ma , 24VDc) connection is there. Interesting is if i place old existing positioner there then it easily move the actuator after pressing (+) and (- ) key in NOINI mode. Is there any problem of lever setting or restrictor setting there.i don’t change any restrictor setting in this newly buying positioner during commissioning there.i am confused if there any setting required in restrictor at positioner during newly commissioning? Anybody here who can advice me kindly please to fix this problem.

[@secretworld7938]

Sir calibration kr ke to dikhaiye aap to only bta rhe ho

[@armanhashmi7962]

Than you sir auto calibration kaise karenge

[@secretworld7938]

Zero and spane kr ke dikhaye

[@shababhasan9496]

Agae pointer zero pr na ho to positioner me zero adjust krna hai ya xp se zero lana hai

[@Sultankhan-pk1qh]

Sir maintenance ka interview questions ka bhi video banaye

[@engineeringconcepts]

Ok dear next video coming soon ...

[@SurajSingh-wk1tk]

Sir ek question hai jo hmara actuator hota h usme saare nut bolt same rehte h lekin 2 bolt bade rehte h vo kyu hote h kya reason h sir

[@engineeringconcepts]

Please come in my WhatsApp for details information

[@SurajSingh-wk1tk]

@@engineeringconcepts please number dijiye sir ..plzz

[@imranfarooque8092]

sir can you clear how many air pressure require in cv...

[@sumeeryadav7933]

Depand u r spring range and actuator size

[@anilkumardwivedi3694]

अधिकतर स्टैण्डर्ड एयर सप्लाई pressure 1.4 kg/cm2 या 20 PSI होता है और इनपुट एयर सिग्नल 0.2kg/cm2 से 1.0kg/cm2 अथवा 3.0PSI से 15 PSI होता है। facebook.com/dwevedianil/ LIKE and SHARE our page.

[@ganeshchavan1815]

Nice