Cathodic control Box

[cbranter]

In the oilfield we have cathodic control boxes that use DC current to protect the metal flow lines from corrosion.

Q: these boxes are off limits to operators , who in the past have opened the boxes and recorded the V and A measurements for engineering analysis.

In order to keep them out of these boxes , but still let a non electrician person gather the data , we have considered installing viewing windows in the door and moving the V /A toggle switch out to the front door.

Has any one had to work through this type of scenario?

Also does the door to these types of junjction boxes need to be pad locked?

 

[jerm]

In the oilfield ...
Has any one had to work through this type of scenario?

I think the complete lack of any reply to date means "no".

I've done a lot of oilfield work, but all the lines are big black PVC. No corrosion, problem solved.

 

[jerm]

Strange coincidence, I just called in to get my marching orders for tomorrow and found out that I'm starting on a new job to replace 26 poles in the aforementioned oilfield. They were brought down during our recent ice storm. Fun stuff.

 

[Rockyd]

Haven't ever played in that end of the spectrum. Am thinking Rosemount used to make all kinds of off the wall housings for instrumentation boxes for classified spaces. might be something that direction.

Might be able to find out in a week when "back out on the line".

So what are they using to gain information on pipe? Since BP got smacked for spills up north, they've been pigging the TAPS line on a serious scedule. May depend on type of field your in too (sour gas?) as to Gathodic protection.

Pigs are for scraping and some have "smarts" for detection of pipe thickness, etc.​

 

[stickelec]

You could install a window-kit and still maintain the NEMA 4 or 4X. Go to the link and select Window Kits for the pdf file.

http://www.hammondmfg.com/EE_ACCESS.htm

 

[Jraef]

Windows are fine, as long as the enclosure integrity is maintained as mentioned above. You also would need to make sure the switches are rated for direct exposure to the elements, i.e. NEMA 4X.

I used to build panels for a cathodic protection manufacturer; we used boxes with dead-front panels where the instrument displays were cut into the inner door. That dead-front on the inside was padlocked closed so that only the electricians could get inside, but the exterior door was provided with quick-release catches for the operators to take their readings. The only reason we did it that way was because the dead-front kits (hinges, catches and an extra back panel) were cheaper than N4X window kits for Hoffman enclosures. But if you are going to retrofit in the field, I would think windows would be easier. If all of the boxes are the same size, buy a few replacement doors and install the windows and switches in the shop, then take the entire new door out and swap it in the field. Bring the doors back that you removed and use them for the next installation.