Convert Ex-d Panel to Ex-p

I do not believe you can convert an Ex d enclosure to an Ex p enclosure and re-certify it as such as far as I am aware. The protection schemes and box construction are quite different between the two.

Be aware that Ex p protection is not just connecting an air line to a box and applying positive overpressure.

Your best option is either replacing the Ex d enclosure or getting a new Ex p system built. Both will require some system downtime as the equipment inside the Ex d enclosure will need to be removed and reinstalled in a new enclosure and certified as a complete package by a suitably qualified Hazardous area workshop.

Also, you are not allowed to drill and tap a hole in an Ex d enclosure unless you are properly certified to do so (this must be done by a certified workshop or the original enclosure manufacturer).

The comments above relate to the European ATEX and IECEx standards, American standards may be more lenient in their requirements.

Have you tried contacting the original Ex d enclosure manufacturer for advice or replacement?

Yes, we have contacted some of Ex-d panel manufactures, and all suggest to replace the Ex-d panel. Which it requires downtime for the plant.

Probably not as much downtime as an explosion....

Well you cannot run the equipment with a damaged flamepath. Well perhaps...………...

Is this a Zone 1 or Zone 2 application (gas present often, gas present infrequently)?

Can you move the Ex d box into the safe Zone or adjust the plant operation to temporary move the Zone away from the Ex d box while it gets replaced?

You may be able to temporarily run it as it is if you perform a risk assessment, but it really depends on your capabilities to perform this and the level of risk you are willing to accept (and local standards and regulations).

For example; you may be able to temporarily accept a higher level of risk by stationing staff with gas detectors near the damaged Ex d box and shut down the equipment in the event gas is detected. This is ONLY an example of possible risk mitigation.

Refer to local standards and regulations and the advice of a hazardous area inspector to see if any of this is a possibility for your plant and the standards it is running to (but be careful).

Let us know what you come up with.

I have come across this a few times from our supplier and customers.

Has the manufacturer (I am assuming you have contacted the original box manufacturer) you contacted assessed the level of damage based on photos you have provided?

Light damage to an Ex d flamepath can potentially be fixed (with buffing) or even accepted by the box manufacturer without having to replace the box, also it depends on the direction of the damage and length of the scratch.

It all depends if the scratch or gouge has compromised the flame path integrity, so there may be hope yet the box doesn't need replacing (or replacement in the future to reduce risk but allow the plant to continue to operate now).

Can you post a photo or two clearly showing the damage?

Is it a really bad gouge across the flamepath that occurred during maintenance when the lid was removed or something else?

there are 2 panel Ex-d which damage on the flame path. Both located in the offshore platform.

The 1st one located far away from process area, based on layout, it is located in utility area exactly beside the living quarter. And the distant to process area around 12 meter.

The 2nd one located in process area, with the nearest distant from flanges (gas pipe) is 5.5 meter. This panel is for diesel centrifuge. The distant to diesel tank around 1.5 meter.

We have put the mitigation, to use gas detector prior operate the panel manually.

Here I attached the picture for both panel.

Thanks for your sight.

What gouged that? An angle grinder?

If you modify this panel, who is going to certify that it is Ex-p? Do you have a certifier on board to do this for you? Are they happy with what looks like a 50mm distortion in the flamepath faces? If they are, what will your instrument air consumption be like?

It's along time since I worked with hazardous area kit but It wasn't an area where make-do-and-mend was a valued operational philosophy in the 1990's and I don't think much has changed.

My suggestion is replace like with like & maintain your certification, insurances, lives and limbs. If you find yourself to a less than safe solution, walk away. It's easier to find a job from leaving one than from gaol or the grave.

What gouged that? An angle grinder?

Nope, the boxes are Aluminium construction with a greased surface and generally sealed so well they can develop a negative pressure creating a vacuum seal, so when the lid doesn't open easily the operator just hammers a screw driver into the gap and tries to wedge it open (inevitably damaging the flame path).

Unfortunately I have had to replace boxes because of this. That and round lid Ex d boxes where the operator didn't bother undoing the locking grub screw creating a nice deep gouge all the way around.

This form of damage is unfortunately is not repairable as it affects the flame path creepage and clearance distances.

You gotta do what ya gotta do.

If you cannot afford to lose,you should not gamble.

What do the underwriters say about it?

By making this issue public,you (and/or your company) are now legally aware of the problem,and are potentially liable for the consequences of inaction.

Getting proper authorization for replacement and downtime will probably be more problematic than the actual replacement .

Remember,the executives don't want to be bothered, they just want to "Get their life back."(Remember the BP Executive?).

They do not really care about the warm body casualties.

That is simply the cost of running a business.

Good luck!

Down time is money. Have you thought about physically installing a complete replacement, including the routing of the cabling and piping, up to the point of connection? With this done the only down time needed would be to remove the old connections and connect the new.

A fools folly Sir!
do you have the right equipment to certify your quest? Do you have the expertise in-house?

I think not!

Ex-P is used when the enclosure contains other equipment that is NOT Ex rated. The enclosure will have interlocks on the doors, pressure monitors and a dedicated air supply from instrument compressed air.

looking at your photos, I wonder how the faces were damaged and moreover why you haven't changed that enclosure out for new instead of working on a plan that will not work!

Change the bloody box or we will be reading about another Piper Alfa!

There was a guy running around here by the name of Mickey. Last job he said he had was working for a sorcerer as an apprentice. After a number of Jerry rigged engineering snafus, the management sent him packing. Last I heard he was hanging out at an amusement park.

M.I.C.K.E.Y..... M.O.U.S.E!!

<...small damage in the flame path....the panel continuously running...> indicates the the facility is now some sort of bomb. Isolate it immediately and replace the <...Ex-d...> components like-for-like before re-energising.

Converting from Ex-d to Ex-p, even if it were possible, will not overcome the problem of <...it contains wiring & control PLC...>. Such equipment is only maintainable during a shutdown and <...the panel continuously running...> prevents this from taking place at other times.

In summary, the installation is incorrectly designed and constructed and maintaining it in use will make one extremely unpopular with the facility's fire insurers, assuming everyone survives the inevitable explosion that is about to occur.