Explosion Proof Wiring Systems

[pepparz]

Im not having a dig just saying that experience isnt everything and just because someone has done something for a long time doesnt mean there good at it or know what they are doing

now this does make me chuckle.ive got the qualifications but these are just bits of paper that anyone can get, the real proof in the pud is experience and having every single job inspected and passed by inspectors who have said they would be more than happy to give me recommendations but i dont have to justify myself, im earning a living and in 25 years have never been unemployed or sacked and had only 3 employers.

 

[Darkwood]

I feel this explosion risk is nothing compared to what American ex-secret files have shown ...regarding nuclear accidents where they were literally moments away from a nuclear bomb going off on home soil in poulated area..... i take it this aint the kind of explosion under discussion?

BBC News - US plane in 1961 'nuclear bomb near-miss'

 

[timbobelfast]

Peppaz, I think you have been exposed to too many IIC gases!

 

[pepparz]

Peppaz, I think you have been exposed to too many IIC gases!

hydrogen or acetylene?

 

[Knobhead]

I did my gas training at the Safety in Mines Research Facility. A fantastic place, explosions galore!

The test rig for testing motors is fun, they have a motor with an over large flame path. Quite spectacular when the surrounding atmosphere is at just below to upper explosive limit.

 

[pepparz]

Not asking to prove yourself just the regs so can have a quick look to satisfy curiosity

the reg is BS EN60079 series. does that satisfy you on this sunny saturday?

 

[pepparz]

I did my gas training at the Safety in Mines Research Facility. A fantastic place, explosions galore!

The test rig for testing motors is fun, they have a motor with an over large flame path. Quite spectacular when the surrounding atmosphere is at just below to upper explosive limit.

is that near area 51 in nevada?

 

[SPARTYKUS]

is that near area 51 in nevada?

I wouldn't know, I am actually a heavy goods train driver, I appear to have registered on the wrong forum. Damn this predictive text !

 

[pepparz]

I wouldn't know, I am actually a heavy goods train driver, I appear to have registered on the wrong forum. Damn this predictive text !

Hahaha nice one.

 

[D Skelton]

after having time to reflect on my posts ive decided to apologise to D Skelton, sorry mate it was wrong and unfair of me to mock and name call, hope you will accept this and think no ill of me.

Thank you, apology accepted.

 

[Engineer54]

ill just add this, the gap does not occur during a explosion its always there and it is measured with feeler gauges. just remember to use a silicon based grease to prevent the flamepath from rusting.

Well it is and it isn't...lol!! Machined flat faces without seals or gaskets will always have a gap. As far as i remember the limit on any such gap on flameproof flanges and the like is around a max 0.004'' depending on the type of gas/vapours involved. You measure any such gap in accordance with manufacturers recommendations to ensure that the gap does not exceed specification after the flange bolts have been correctly torqued down.

In the event of an internal explosion, the internal pressure created, will in it's own right expand any such gap, but still within the tolerances of it's type testing....


Things may have changed a little these days, as now i understand that Aluminium flanged enclosures are now often used in division 1 / Zone 1 - 0 and Ex 'd' equivalents. I've only ever used the heavy cast iron type enclosures!!

BTW, you didn't mention what method of IR testing you use at your site??

 

[Des 56]

The magic of air filled flameproof enclosures has now been revealed to the masses by pepparz in this thread
I am at a loss why he felt the need,some have worked in the mines most of their lives and didn't feel that urge
Was it something someone said?

and
Part 2 will now take the form of intrinsic safety and the use of the intrinsically safe Metrohm

Away to go then lad
This will be for the non explosive members benefit and general forum educational purposes perhaps

Next term oil filled switchgear as flameproof enclosures,a concise history

 

[Knobhead]

I'm dropping out of this before I blow a gasket!

Sorry a 0.005" FLP flange.

0.004" Min 0.006" max.

 

[Darkwood]

I remember when i had a customer where they filled gas bottles from nitrogen to oxygen thus the site was no Mobile Phones .... bring me in with a intrinsically safe mobile and see all the management start flapping because i answered my phone while working on a motor next to a oxygen filling tank.... they had never heard of a safe phone for use ...even got funny looks in tesco petrol station and when i said its intrinsically safe she said whats that mean .... told her and she went UH! i have to follow rules .... told her its a shame when your guidelines and your boss are so ill educated ....makes you wander exactly what they get payed for!

Went into have a chat with manager of local tesco's branch a week later and still they stuck to policy ... i left saying i thought you was a manager with discretion at your will.... seems you just another puppet not allowed to think for yourself.... he didn't like that at all ... i still get daggers when i see him lol .... hasn't stopped me using the phone though sometimes i do it on purpose cos im evil like that

 

[pepparz]

ah yes the oxymoron that is the intrinsically safe tester. i would personally IR in the conventionally way in the safe area,but if you need to do it in zones 2 or 1 on the kit make sure you do a gas test and have a hotwork permit.
pit electricians, ah the ones who when ty wrapping swa above ground still leave large drip loops between every ty.