Answer / prem

in any application single seated valve permit 2 to 3% leak in full closure position advice to use double seated valve to ensure tight shut off.

Answer / praveen kumar

double seated valve-this type of valve used in high pressure line to minimze the force applied to the stem by process fluid pressure across the fluid.
Explanatioin:-there will be two opposed force vector, one generated at upper plug and another generated at lower plug. the plug areas are approximately equal, then the force will likewise be approximately equal and therefore nearly cancel. this make for a control valve that is easiler to actuate.

singlw seated valve used to low pre applications to control accurately

what are the documents(Construction point of view for a process plant) submitted by contactor initially entering in to new site for client?

0 Answers   NTPC, PSU,

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why we take %i0.0 as input for twido plc

0 Answers  

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what is consistency transmitter and describe its working?

1 Answers   Emami,

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what is the diffrence between plc&dcs

4 Answers   HCL, Hindustan Zinc,

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If a control valve is hunting means means if we are giving 50% to the cv, the cv will open at 51% then slowly slwoly it will reaches 49% , then it will reaches again 50%, this type of action occured frequntly.. so what to do for solve this problem. The possible cause is in volume booster or positioner's relay.. positioner is double acting .. and make siemens..sipart.The cv is double acting and mounted for anti surge operation, it having 4 nos. volume booster, one sov, one positioner, etc..?

2 Answers   Gujarat Fluorochemicals Limited (GFL), Shell,

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Convert a pressure, level, flow, or temperature process variable value into the appropriate pneumatic or electrical value given different types of instruments.

6 Answers   Jindal, MCL, Thermax,

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What is the three element? And how it work?

1 Answers  

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hello this is dhinakar i am completed my instrumentation engg . recently i got job in sugar industry side. i like to ask one question can any one say what are the things i have to follow know more about industrial instrumentation,,,,,,,

6 Answers  

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in split range control valve,two valve should be in two different line and that should have some distance,and we have only one positioner feed back link.so how we connect one feed back in two control valves?if you have picture please forward me.my email id kb.syamkumar@gmail.com

2 Answers  

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Any Transmitter Range (Span value) start from 2?

1 Answers   Exxon Mobil,

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Can anybody explain what is the different between ESD & PLC

1 Answers   ADCO,

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why 1 to 5 vdc is used for output measurment

4 Answers  

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