repiping a Plant 2

[wamtp]

My facility just suffered a catastrophic fire. More than 60% of the Plant is in ruins. Corp says "rebuild". Now is our opportunity to do it right. All the main systems, Air, Treated Water, Gas, and Potable Water entered the Plant in the area that was lost. Any suggestions on piping schemes for our "new" systems? Thank you, wamtp

 

[MikeHalloran]

I worked briefly as a maintenance mechanic in a chemical plant in New York State. It was winter, and we spent a lot of time thawing and rodding out process waste lines. Too much of that time was spent disassembling pipe just to get access to other pipe. The experienced mechanics were a varied lot, but all agreed that using an elbow in a pipe subject to freezing was not a real good idea, at least from the perspective of someone who had to remove that elbow to unclog the pipe. A cross and a couple of plugs at every direction change would have saved that company a _lot_ of downtime.

Your maintenance mechanics can probably offer many excellent suggestions, carried in a stream of insults and profanity. Steel your ears, ask, and listen.



Mike Halloran
Pembroke Pines, FL, USA

 

[rmw]

We don't really know what you are going "from" to help you get "to" a better system. Can you give any known problems with the piping that burned up?

rmw

 

[Drazen]

I will refer to MikeHalloran again. If you need general suggestion, that is: allow enough space for piping systems! Don't squezee bunch of piping in some dark corners, you will have endless problems with them during entire plant life, even if there are no valves or devices in such corners.

If you need to lay piping in more then one row, vertical distance between rows must be sufficiant to allow safe and proper joining/dismantling (was it welding, bell pulling, thread assembling) any pipe lenght throughout the plant. That will save you lot of downtime over the years. You make real money to your boss with such savings!

If you want to do it right, fight with the architects for space. They will allways tell you that you don't need so much space whatever you demand, but you know the best!

 

[SlideRuleEra]

Size the piping and locate valve, fittings, etc. in accordance with good engineering practice to minimize system losses.

Give advance thought to how elevated piping components will be accessed... don't want to have to install unnecessary platforms and ladders. With that said, wait as long a possible before building any access platforms. Operations personnel will quickly reveal the strengths and weakness of this advanced planning. Then you can provide access where it is really needed.

http://www.SlideRuleEra.net

 

[stanier]

GEt a copy of The Piping Guide by Sherwood, Piping Design Manual MW Kellog and Piping Handbook. Read and learn. If you dont have the time engage a very experienced piping engineer and draughtsman and pick their brains.

Alternatively move to a job that you can cope with!.

 

[NozzleTwister]

wamtp,

I recommend that the first thing you do is bring in some competent Piping Designers and a Piping Engineer.

Then they need to start taking a lot of pictures of EVERYTHING, piping, equipment, support steel, ALL PIPE SUPPORTS, instrumentation, electrical etc. Those pictures will become invaluable once the fire damaged piping has been demo'd. If you don't have up-to-date drawings of your plant, have the piping designers make sketches of all lines before demo.

Now that you have that started, you need to find out exactly what Corp. means by "rebuild." I was involved in a refinery fire rebuild a number of years ago and "rebuild" meant to duplicate the existing plant regardless of whether some systems were poorly designed. Unless it was a safety issue, it went back in just like it was. The philosophy was to keep engineering hours and down time to an absolute minimum.

If your company is willing to spend a little extra time and money to improve the facility over what it was then that's great. The existing layout, drawings, photos and sketches will still be good starting point. As the others have suggested, talk with the operators, maintenance folks and plant engineers to find out what needs to be improved as well as what was already working great. This may also be a good time to address any de-bottlenecking issues.

It's very unfortunate about the fire and I hope nobody was injured. You need to address what caused the fire and certainly take care of that issue everywhere there may be a risk.

The fire rebuild that I was involved in was started because a corroded hydrocarbon line burst open and that hydrocarbon found an ignition source. Parallel to the fire re-build effort, they checked the piping for the entire unit and eventually needed to replace more pipe due to being corroded beyond its retirement thickness than what was damaged in the fire.

To me, this situation is an ever increasing concern as we see facilities remain in service for many years beyond there original design life. Process and feed changes can also reduce the life of a system. Continued good maintenance and inspection practices are the key to identifying systems that need attention before they become a problem.

Good luck with your facility.


NozzleTwister
Houston, Texas

 

[pipingdesigner]

I must agree with NozzleTwister.

....bring in some competent Piping Designers and a Piping Engineer.

It's all very well knowing the do's and don't when dealing with one or two lines, but if you are talking about a rebuild, then you need the knowledge that pipers will bring to the job.
This is as important as bringing in an architect, a structural engineer and a process engineer.



pipingdesigner

http://www.pipingdesigners.com