Pipeline ESD 1

[Julio8287]

Hi There

I'm in a SCADA commissiong for a gas pipeline (408 km), Emergency Shut Down from Control Room is being set up:

1.- One for metering station, ESD closes all MS valves.
2.- One for Pressure control station, ESD closes all PCS valves.
3.- One for Plant Facility Receiver, ESD closes all PFR valves.
4.- Finally a General ESD that closes all valves.

I would like to know about "standar" or "criteria" to put this ESD in SCADA system.


Thanks in advance

 

[zdas04]

For a pipeline I never tolerate a SCADA system being involved in either ESD initiation or shutdown. There is a lot of reasons for this. The main one is we keep getting batteries stolen. Without a battery, the SCADA system goes silent and all ESD lose their latching signal and go shut.

If all the valves that should ESD are built to spring to their ESD position (usually shut, occasionally open), then the "control" scheme is to shut off control air and vent it (or open a switch). Everything else "fails" in its defined position.

David Simpson, PE
MuleShoe Engineering

http://www.muleshoe-eng.com

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

"It is always a poor idea to ask your Bridge Club for medical advice or a collection of geek engineers for legal advice"

 

[BigInch]

Remote shutdown with SCADA activating the ESD valves is common practice everywhere I've worked. Maybe you need some better security features David.

Other than that, I don't understand the OP question. What do you mean by, "put that in the SCADA system", writing the control program?



**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[JLSeagull]

Perhaps the question pertains to shutdown initiators - the causes for a shutdown instead of the type of logic controller.

 

[BigInch]

That could be anything from an operator observing low pressure-high flow, an algorithm between hydraulic model predictions vs actual transmitted value, to a telephone call from the Sheriff.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[Julio8287]

Thanks to everybody:

BigInch, "put in the Scada system", I'm talking about shutdown initiator from control room, they will be programmed like push buttons in the control system, are there some rules to put this ESD in different places?

Bye There

 

[BigInch]

Not that I know of. Sometimes displays are built into the control room's wall, sometimes they are entirely on a computer screen. ESDs are accessable anywhere within what could be many drill-down screens each showing increasing levels of detail of individual sub-systems. As you drill down, you may only have access to the general ESD shutdown and the shutdown controlling the particular subsystem you have up at the time.

The overall screen will have the general shutdown prominently displayed and possibly all local shutdowns too, each local shutdown contained within a smaller box devoted to the particular subsystem, but not always. Sometimes you have to drill down to the subsystem to remotely activate that subsystem's ESD. Just depends on how you want to write your SCADA spec. I think its a good idea to have access to all shutdowns from the overall screeen, but sometimes a whole system is too complicated to display each and every shutdown on the overall display. In that case, you may have access to the primary facility shutdown and ESD valves on the overall, and have to drill down to get access to subsystems within that facility, such as an ESD for the one pump area only and a separate ESD for another pump area, an ESD for lines going to the tank farm, etc.

Typically the SCADA vendors have a customary way of making their particular displays, if the owner does not have a particular way they want it done, most somewhat similar, but they can vary from vendor to vendor. Then again, some companies have standards to show open valves green and closed valves red, opening valves blue and closing valves yellow, some companies like the reverse, some companies use a flashing color to indicate a changing valve position. Some companies like to see their running pumps red and their stopped pumps green, I like the reverse.

I do not like to see a remote control to open an ESD valve via SCADA, unless you get a local OK too.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[zdas04]

OK, you guys are talking about control rooms and such. My world is building substantial fences around above-ground valves to keep the harvester from hitting them. In a farmer's field, power for SCADA-logic comes from a solar panel and battery. No way to stop the Meth Labs from stealing them, and we lose a lot of them off well sites. If I lose monitoring ability at a wellsite I still have gas flowing. If I ESD a line because some doper stole the battery, the line is shut down.

I'll shut up now and let you go back to the point of the thread.

David

 

[BigInch]

Here's a remote ESD (white actuator near back fence) We put the solar panels behind big fences with backing posts and razor wire, or on masts & poles, batteries in a vented concrete or metal box enclosure. Works for us.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[BigInch]

Both diagrams have access to ESD and all valves with one click.

Overview

Drill-down 1 level to,

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[786392]

Nice learning info.My dear BigInch

Best Regards
Qalander(Chem)

 

[BigInch]

Thanks Q
Didn't know what else to say.
---------------------
BTW, the solar panels are in an area where even buckets with holes in the bottom go missing.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/

 

[dcasto]

Make sure any ESD function in the SCADA has at least one level of ARE YOUR SURE YOU WANT TO INTIATE THIS ESD?

 

[BigInch]

I'd suggest "BOSS" level, unless you heard the noise and can see the flames.

**********************
"The problem isn't finding the solution, its trying to get to the real question." BigInch

http://virtualpipeline.spaces.live.com/