Transformer temporary Blast Wall material? 1

[wanting2learn]

We are looking to add a new transformer to our distribution switchyard (outdoors) and to construct some blast walls. This involves doing some work close to the energized gear. To make the work area safer, and since it is not possible to de-energize all the gear, we are hoping to erect a temporary barrier between the energized gear. This temporary barrier needs to be about 30 feet long and 30 feet high. Does anyone know of any company that makes such a temporary protective barrier (which is compliant with the necessary safety codes, including the NFPA code)?

 

[ScottyUK]

Blast walls tend to be permanent by virtue of the heavy construction required. I've never heard of a temporary blast wall. You might want to ask this question in the civil engineering forum - I doubt many of those guys frequenct the electrical fora and you will probably get a more knowledgable response to your question.


Just an opinion on something you wrote:

It's almost always possible to de-energise the gear, it's just usually a pain in the ass from an operational perspective. If working conditions are hazardous enough to require it to be switched off to protect the workforce then commercial reasons for leaving it energised don't count for much in the eyes of the agencies responsible for safety enforcement, e.g. HSE, OSHA, whoever is your local equivalent. I would not want to try defend the reasons why it was not possible to de-energise some equipment involved in an incident while being cross-examined by an HSE Inspector in Coroner's Court. Much better to defend why it needs to be de-energised in front of the company management.


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If we learn from our mistakes I'm getting a great education!

 

[DrDrreeeaaa]

I agree with Scotty's opinion on this.

 

[wanting2learn]

I appreciate the feedback. Just to clarify one thing, the structure I would have been looking for was just meant to be temporary, as the work on a more permanent blast wall was being done.

Thank again for the feedback you guys.

 

[ausphil]

Have seen blast walls erected by putting up shipping containers between the hv equipment and, in this case, an office. 30 feet by 30 feet sounds like 2 containers on top of each other (sort of like lego for big kids)

ausphil

 

[RRaghunath]

wanting2learn,
I happened to see IEEE Std 979, which explains putting up a temporary fire-resistant barrier with Sheet steel or other non-combustible material for maintenance purposes.
You may like to refer.

 

[BJC]

Look at the big "lego" type blocks. They are 2x 2 x 4 and have indentations and projections like legos. 300' is high for something like that, it might work with some steel in the right place.
The people that make your vaults probably make them. I am sure people rent them like Jersey barriers.

 

[ScottyUK]

Ausphil,

Good point about the shiping containers - I have seen them used to contain the debris from demolition work. Not sure how much use they would be in an energised switchyard due to physical size, and there's great potential for touch and transfer voltages in unexpected places if large metal structures are introduced to that environment without a lot of attention to the earthing arrangements. Difficult to comment objectively without seeing a plan of the area.


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If we learn from our mistakes I'm getting a great education!

 

[rcw retired EE]

We used a steel panel product that was filled with concrete. It was cheaper than a concrete and rebar blast wall for transformer fire containment. The 2m x 2m panels required a steel support stucture for support and then were bolted togther, about 10m x 12m.

The blast panels were CSA & NFPA approved adn certified. But I didn't like the steel suface material in close proximity to the 230 kV.