Question with no good answer (code related) 1

[justinwest]

I've been tasked with helping standardize flowlines on natural gas wellsites. No code seems to step up and claim this area in it scope, though B31.8 expressly excludes the lines from the wellhead. The lines will be from Wellhead to Separator to TOC meters.
Our best consensus is B31.3.

Has anyone encountered this delimma, and what was the ultimate decision?

We have also thought to break it down by what line is carrying what i.e., 31.4 for condensate, 31.8 for gas after the separator, 31.3 for the raw gas prior to separation, etc.
This could very well turn into a chaotic mess during construction!

 

[BigInch]

Don't worry. Using a number of specifications won't be a problem, if the design drawings clearly show the "Code Breaks", material is specified accordingly when purchased, referenced on the drawings using mark numbers tied to material lists and the purchase specifications.

http://virtualpipeline.spaces.msn.com

"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein

 

[Sid7]

Are the wellsites on land or subsea? Just curiousity.

Siddharth
These are my personal views/opinions and not of my employer's.

 

[BigInch]

Sid7,

It could be very much relavent, if the wells are located in the Minerals Management Service regulated offshore areas of USA. They have their own design code for wells & flowlines (upstream of separators). Downstream of separators, "pipelines" must be designed to either Title 49, part 192 or 194, depending if gas/multiphase or liquid.

http://virtualpipeline.spaces.msn.com

"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein

 

[justinwest]

The wells are onshore and under the jurisdiction on the Texas Railroad Commision, and they offer no direction in designing piping systems.

 

[BigInch]

When I was working in the Zachery & Zapata Fields near Laredo, I had the same problem and I decided to design everything from the well head on out to B31.8 & CFR Title 49, Part 192, even though neither were required by any authority, except where we crossed a public road RoW. We had mostly lighter condensate loads, so I never thought I needed to design for liquid lines. If you have some 100% condensate liquid lines, you might want to do that.

http://virtualpipeline.spaces.msn.com

"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein

 

[Sid7]

PD8010 or DNV OS F-101 may fill in as well if you were to work in North sea or other places. But as its the fact that you are in Texas hope BigInch's advice should help you out.

B31 groups can be of great help when sif's come in place as of manifold. And the flowlines if rigid wont be having any fittings mostly.

Now I learnt that MMS has its own code for this application. Thanks BigInch.

I do not want to hijack this thread but like to know how does MMS CFR goes alongside with B31 codes? This is new information for me as I have never worked on MMS regulated project. So I wonder if you have more than two US codes for the same application within US territory?

Regards,
Siddharth

Siddharth
These are my personal views/opinions and not of my employer's.

 

[BigInch]

This is how I remember it. There may have been some changes since I learned these.

CFR Code of Federal Regulations
Title 49 is Transportation
Part 190s are Pipelines (192 & 194)
They cover federally regulated pipelines (Interstate & some Intrastate pipelines)
The CFR pipeline parts are the legal requirements for covered pipelines. They generally follow B31.3 and B31.8, but may vary in some aspects. I can't name a specific variation though. Consequently, since B31.4 & 8 really arn't "legal" for US pipelines, I never looked at them until I started working internationally where, as you know, are referenced frequently.
----------------------------------
Each State can have their own regulations, but most states
defer to the CFRs. Always check with the state "Railroad" commission, or similar authorities.
----------------------------------
State Offshore Areas to a 3 mile sea limit, or 3 league sea limit in the case of Texas (set as originally claimed by the Republic of Texas), are regulated according to the state requirements and, if the pipeline is an interstate pipeline add the CFR Title 49 regs too.
-----------------------------------------
Federal Offshore Areas beyond the above state limits
Pipelines (Not Flowlines considered being from wellheads to separation, compression or treating facilities) are regulated by CFRs.

Minerals Management Service (MMS)
regulates the well heads and flowlines
------------------------------------------------
Federal Inshore Areas are regulated by the Bureau of Land Management, BLM which often prescribe more environmentally related criteria rather than specific criteria for the pipe... "Be sure its painted BLM green", etc.

That's how I remember it.

http://virtualpipeline.spaces.msn.com

"We can't solve problems by using the same kind of thinking we used when we created them." -Albert Einstein

 

[dcasto]

There is no code you must follow unless you meet the revised scope of jurisdiction under DOT 49CFR 192 as adopted by each state. The TRRC adopts it and has jurisdiction.

However, because the state can exercise its option at anytime to make those lines jurisdictional, it just as easy to follow the 192 rules for the design and installation. There is little in any impact to the cost, as amatter of fact it's cheaper than using 31.3 in most cases. There are some things in the design you will most like skip and thats making the line pigable (unless they are over about 1/5 mile). Then your operations and maintenace proceedures are your selected practices and they do not have to follow those section of 192 100%, but 192 again is not that onerous.