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View Full Version : Flare Fittings - Illegal?



Derek
15-07-2002, 12:54 PM
Here's todays office discussion and one for the European Legal Eagles among you.

Refrigeration Safety Standard En 378 P 1 to 4 has been harmonised under the Pressure Equipment Directive.

The PED is law under UK Pressure Equipment Regulations.

Flares (except for instrumentation) are not permitted under En 378.

So do the collective think thats the end of flare fittings and is anyone who used them from 29 May this year has commited an offence?:D

Argus
16-07-2002, 09:51 PM
I for one would not mourn the loss of flares. The same applies to Schrader valves, as in my opinion, these things leak like a sieve and caps are often left off.

There must be an inherent problem with a joint that relies on the distortion of the pipe wall for the integrity of the seal ?ESPECIALLY when they are routinely taken apart and reassembled when the metal has hardened.

This type of joint is in fact banned in Holland.

My recollection of EN 378, part 2 states that flares are not banned, but allowed on pipes between 9 mm and 19 mm diameter and only on annealed metal. There is no specific prescription of flare joints in the standard. Oddly, it does not say anything about 6 mm tube??

The mandatory application of EN 378 to the PED is described in the Z annex, but only applies to equipment that is included in the PED ? by no means all refrigerating systems are included in the scope of the directive.

The Pressure Equipment Directive has been in existence for some time now ? the 2 ? year transition period expired last month and compliance is now mandatory in the EC, but it was in formation and available for regular discussion for at least 3 years before that.

Equipment is only covered in the PED from the lowest category level upwards, that is Category 1. Any machines below that are simply not in the scope. This would probably include many systems using small diameter pipe with flares. They would be covered by what is called ?Sound Engineering Practice? ? in other words whatever standard or methodology you were using before the PED came into force in your country. SEP is not defined any further in the directive.

These are broadly defined comments I have made, as each system is assessed on its own merits.

This is one of the more complex directives to understand, especially as a lot of the demonstrations of compliance is dependant on third party assessment ? so called notified bodies.

A lot of industry folk are scratching their heads at the moment with this one....
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herefishy
16-07-2002, 10:27 PM
My understanding (in USA, if that matters) is that the flare ban only applies to manufacturers of finished products or components, but not necessarily the field service technician. I could be wrong, and would appreciate any further enlightment on this matter. :)

Derek
17-07-2002, 11:31 AM
Argus

Yes well stated.

En 378 P2 6.2.3.2 No flare joints on expansion valves, at least that is clear.

Flares to be avoided were 'reasonably practical' (that's a bit like my favourite 'what qualifies as an acceptable leak rate' answer).

As to PED and SEP I believe that using a phase change fluid above 0.5 bar that all vapour compression systems are tied to the PED. Ammonia and any other B1 or B2 fluids must be PED even if they are SEP. The only escape under SEP is the need for a CE mark with the notified body number of course.

The only argument would be if the refrigeration system was not the greater part of the system and was better covered by say the Machinery Directive.

As to repairs herefishy

That's covered by our Pressure System Safety Regulations and I'd find it difficult to sign of on a repair that introduced a flare. My annual written scheme of examination should probably read no flares in repairs stopping anyone acting against best practice.

I suppose the question should be is it reasonable for a new piece of equipment to be delivered with its principal connections being flare joints I'd vote No.

Abe
17-07-2002, 09:54 PM
I for one would not mourn the passing of flare joints. Air Conditioning companies can start providing sweat instead of flare joins

Andy
17-07-2002, 10:33 PM
Hi, Derek
Flares are only one small part of PED, I am by no means clear on PED, but should we not be using a notified body when installing equipment with pipework above 1"nb or a system internal volume over 30 litres? I think there is the capacity for a lot of law breaking out there.
Regards. Andy.

Derek
18-07-2002, 06:22 PM
Andy

Right here's my view and the one that is giving some of my colleagues a few nightmares.

PED applies to all refrigeration systems over 0.5 bar limit pressure as long as they are not excluded e.g. vehicle A/C systems. Limit being max operating plus allowance for operating fluctuation.

Exclusion does not imply 'not applicable' and if no standard or directive exist you should select the closest. IMHO the PED is always going to win in court.

Vessels, pipelines, safety items and assemblies in fact any critical 'fluid wetted' part is covered by the PED.

If you have a vessel (reciever, condenser etc) under 25 bar.litres or a pipeline under 25mm nominal bore you can use SEP. That is unless the operating fluid or the operational environment demand a higher category.

I suggest that means all the content of EN 378 and PED is applicable but you can assess and certify your own products or installations.

If you are Cat 1 to Cat 4 you can use a registered notified body to inspect the design and system or you can set up your own User Inspectorate certified by a notified body who approve you to inspect your own system after they have verified the design (criteria?).

The process applies to any putting on the market (selling, loan, gift) or returning to use of equipment.

In practice I would say that its OK to replace a faulty valve with the same specification valve but converting a R22 system to R407C and fitting a new compressor would need to be done under EN 378 and PED. Here's my flare argument in that I would expect a conversion as detailed to include removal of flares on TEV's and removing flares where reasonably practical.

You can certify a complete installation such as a cold store with a single CE mark but and here's were it all gets a bit flowery it is expected that all principal components will have to be CE marked or CE documented and traceable.

If you class a system as PED and lots will, you will commit an offence by putting a CE mark on it or having principal components with CE marks fitted to it (duh?).

Suppliers should be asking what the application is so you don't buy a Cat 1 valve for a Cat 4 installation. Here they could be committing an offence or assisting you in such an offence.

I expect that all Ref and A/C suppliers now have stocks of CE and non CE marked equipment and a selection of Cat 1 to Cat 4 (but still identical) components.

I also assume all stock of tapered pressure relief valves have been recycled or dumped in a local lay by next to the stack of old refrigerators.

Cynical or what, time for a beer!