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Hydrocarbon Processing's Refining Processes HandBook

Posted by Antony Thomas at Wednesday, November 27, 2013

Hydrocarbon Processing's Refining Processes HandBook

Hydrocarbon Processing Handbook download

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Basic Pipe Stress Analysis-PDF Download

Posted by Antony Thomas at Monday, November 25, 2013

BASIC PIPE STRESS ANALYSIS - PDF DOWNLOAD


BASIC PIPE STRESS ANALYSIS TRAINING

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PIPING DESIGNER -CONTRACT JOB - ABU DHABI

Posted by Antony Thomas at Thursday, November 14, 2013

Forwarded Mail...

Dear Candidate,

We are an ISO certified engineering consultancy firm located in Mumbai and branches in Chennai, Vizag, Delhi, Baroda and catering to major MNC's and EPC's in Oil & Gas, Refineries, Chemicals, & Petrochemicals

We have got following interesting job openings

Urgent Requirement - Piping Designer

Required Qualification


DIPLOMA, ITI

Industry Type

Refinery / Petrochemical / Chemical /Oil & Gas (preferred)

Experience : 10-16 Years

Tenure - 6 Months CONTRACT EXTENDABLE

Location - Abudhabi



Kindly send

your updated word format resume along with the following details

Relevant Exp:
Present CTC:
Expectation:
Joining Period:


Kindly treat this as very urgent.


Await your early response...

Note: Number of openings are available, we would be grateful to you, if you refer your friends / colleagues for further opening...

Please ignore this mail if your profile not matches this job requirement,


We have also got job openings in other fields both in India and Abroad, Kindly circulate this mail and refer your friends and colleagues


Thanks & Regards,

Alekya
HR Executive.

Aarvi Encon Pvt Ltd |
709/710 | 3rd Floor |
Prince Centre l Pathari Road |
AnnaSalai | Chennai-06 |
Tel : +91-44-43406670
E-Mail : alekya@aarviencon.com |
Web: www.aarviencon.com |

Fail Open & Fail Closed Control Station Assembly

Posted by Antony Thomas at Sunday, November 10, 2013

You can see Fail Closed (FC) or Fail Open (FO) control valves in P&ID. What does it mean?

What to do on this situation as Piping Designer.

Before going into action we need to know exactly what happens when the actuating medium fails(most of the cases Instrument Air). See the snap below. It is a control valve assembly extracted from a P&ID

 

 P&ID CONTROL VALVE ASSEMBLY FAIL CLOSE

 

 

 

If the actuating medium fails may be intentionally or accidentally will impact the position of the control valve depends on the type of the control valve.

 

 

Control Valve Fail action may be classified as

  • Fail Closed (FC)
  • Fail Open (FO)
  • Fail Indeterminate (FI)

Fail Closed (FC)

Say a P&ID calls for FC. That means when Instrument air goes off, the control valve will be in closed position. To remove the control valve for maintenance or replacement, we have to open the bye-pass valve and close two block valves one bye one. After closing the valve the fluid will be trapped between  first block valve and the control valve and also between control valve and the second block valve (remember the control valve is now in closed position). To remove the fluid and also depressurize the system we need to drain the fluid both upstream and downstream of the control valve.

So providing drains on both upstream and downstream will solve the problem

 

The below snapshot show the Fail Closed control valve.

 control valve -fail close FC

 

FAIL OPEN (FO)

Say a P&ID calls for FO. That means when Instrument air goes off, the control valve will be in Open position. To remove the control valve for maintenance or replacement, we have to open the bye-pass valve and close two block valves one bye one. After closing the valve the fluid will be trapped between  first block valve and the second block valve (remember the control valve is now in open position). To remove the fluid and also depressurize the system we need to drain the fluid both upstream and downstream of the control valve.

 

So providing drain on upstream or downstream will solve the problem

The below snapshot show the Fail Open Control valve.

 control valve -fail open FO

FAIL Indeterminate (FI)

Say a P&ID calls for FI (Fail Indeterminate). That means when Instrument air goes off, the control valve will be in the position. It will not change its position. To remove the control valve for maintenance or replacement, we have to open the bye-pass valve and close two block valves one bye one. For the worst case scenario if the control valve in closed position when the power goes off. To remove the fluid and also depressurize the system we need to drain the fluid both upstream and downstream of the control valve.

So providing drain on  both upstream and downstream will solve the problem

fc-control valve station

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