Definition of "Root" Valve 3

[MPP-LTD]

I have come across the term "Root" valve on a number of different occasion and I still don't have an accurate understanding of when the term should be used.

I originally thought that isolation valves for instruments (e.g. pressure gauge) was called a root valve. However I have also seen someone refer to the first isolation valve on a sub-branch from a larger header referred to as a root valve - I am not sure if this is a common term in Oil and Gas?

Does anyone have any feedback on this?

Thanks,

 

[RVAmeche]

I'd say a generalized definition is the first isolation valve in a branch or system. Could be a sub-header off the main steam line or the first isolation valve for pressure/instrumentation tubing.

 

[pennpiper]

MPP-LTD,
The answer is "Yes" to all the above.
It is used by different companies for whatever, wherever and however they (the company as a whole or some individual in the company) choose. They just need to define it.

It is important to understand that the term "Root" valve is a function, NOT a valve Type, It is any valve type used for "That" purpose, normally consistent with all other valve types from that commodity's Piping Material Line Class Specification.

Sometimes its possible to do all the right things and still get bad results

 

[LittleInch]

MPP-LTD

I've been working now in oil and gas systems for over 30 years and never heard anyone ever refer to a valve as a "root" valve, but your logic makes sense and like pennpiper says (and he has more experience than me in plant design) it could be different things to different people.

I would struggle to say this is a "common term" though.....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Compositepro]

I, too, have never heard the term 'root valve' in a 40 year career. Maybe it is used for snipe hunting.

https://en.wikipedia.org/wiki/Snipe_hunt

 

[RVAmeche]

Is it maybe a regional thing? I'm on the east coast and it's a pretty common term in industry.

 

[MPP-LTD]

Thanks for all the feedback, we are putting together SOPs and some procedure writers use this word. I have mistakenly thought it was term only for Instrument Isolation valves. The term makes more sense as first isolation valve of any branch, given that a root is like the bottom / start of a tree or plant. Anyway I fairly unimportant question but it was something that was annoying me for a while! Thanks.

 

[DGrayPPD]

A root valve is a pretty common term for me as well. I live along the gulf coast and most of my career has been in the oil and gas field.

But yes, "root valve" is just a term used as to indicate the first isolation valve following a take-off from a larger header. For me, the term has been used for vents, drains, and instrumentation. I have also heard the term used for equipment isolation valves as well, although I'm not sure if that is as common or if it is just something I hear where I am.

PIP PNC00005 "Design of ASME B31.3 Metallic Piping Systems" states:

3.3.3.6 Small Piping Root Valves

1. For all process services, branches NPS 2 and smaller shall have a
root valve located as close as feasible to the run.​

2. The root valve shall be no farther than three times the branch
diameter (except for insulated lines) measured from the far end
of the boss to the near end of the valve.​

3. Unions shall not be installed in the pipe section between the
main pipe run and the root valve.​

3.8.7 Utility Stations

3.8.7.3 Root valves shall be provided for each utility take-off connection
from a main header or auxiliary header that cannot be taken out of
service without shutting down a complete processing unit or
operating facility.​

"Thinking is the hardest work there is, which is probably the reason why so few engage in it."

-Henry Ford

 

[Compositepro]

Google search indicates that root valves are a special type of valve with multiple ports used for instrument isolation and mounting gauges. So a simple ball valve used for instrument or branch isolation would not be a root valve.

https://www.google.com/search?q=roo...eAhUJTN8KHTMcD3kQsAR6BAgFEAE&biw=1366&bih=604

 

[Compositepro]

I started my reply before seeing DGrayPPD's post, just to be clear.

 

[crshears]

Not contradicting anyone, but in my experience a root valve is, as pennpiper wrote, a functional descriptor, synonymous with a master valve, which is the first one in a series of two, the latter being the martyr valve, the idea being that the master valve is normally open and is only closed occasionally as the service permits to confirm its operability, with the martyr valve normally used to perform controlling, throttling or isolating functions. As such it is the martyr valve that takes a beating, hence the name, with the master serving to provide a reliable isolating point for the martyr valve's replacement.

CR

"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]