Holly Flare Tip Batman!!!!

Not being either an engineer or metallugist, but I would have thought that most of the heat is concentrated above the "falnge, just above the middle of the visible flames, Secondaly I imagene much of the heat islost pretty quickly in the strong winds.

OMG did I really just answer that question - what a geek!

Imppressive pictures though.

Simon

Simon,
I know where you're coming from but, the radiated heat alone can be felt from the walkways on the south end of the platform!!

Oh, and thanks as it was me who snapped the pics.....

Cheers,
Ali

Ali,

The piping and flanges are most probably made from a material such as Inconel 625 or some other form of Chrome Moly. It's hideously expensive and usually only available from the US. It's good for working temperatures up to about 1000 deg C. Sometimes due to the temperature the joints are actually welded using weldable gaskets, as per the attached picture.



Justyn.

BTW,

It's also a bitch to weld, you have to preheat the joint to a minimum of 350 deg F / 180 deg C before starting the weld, and maintain this temperature throughout (normally using ceramic heating pads), it can get a bit uncomfortable for the welders.

how do people know all this random stuff?

Simon,

It's my job.

For a really obscure observation if the flare was produced in the UK then it probably came from Airoil Flaregas, West Drayton, now part of Hamworthy Combustion, Poole.

How did I come by this trivia? ex-customer of mine.

Jono

Hi Justyn,

Technical question....

.....so why would you use a weldable gasket if you could just have a bit of pipe welded on?

Thanks,

A

A,

quote:

.....so why would you use a weldable gasket if you could just have a bit of pipe welded on?

I don't really understand your question.?

What I,m saying is when temperatures are at the extremes, and maintaining a seal is critical (safety), this method of joining flanges is sometimes used. (Not very often however due to the extremely high cost.)

NB - The picture was to just to show an example. Something like that wouldn't be used on a flare tip, there mainly for high pressure services ,ie above 50 Bar.


I,ll just get my anorak, the 19.40 from Crewe is due in, wouldn't want to miss it.

Justyn.

Justyn,

I do understand the concept...... and all about the safety aspects.

I will try and word this question differently...

As you quite rightly say, using a weldable gasket is very expensive. Therefore, why would you choose that option over cutting the flanges off and welding a 'straight through' piece of pipework on?

Does that make any more sense?

A

A,

Yes, your question does now make more sense. The reason is in the event that you require access, you would have to remove (cut out a section of piping). Re-Instatement would then be a problem esecially on the size pipe I have shown (rules regarding weld distances, X-Ray radiography of welds once re-installed etc (ANSI B31.3 Refers)).Also this operation could only be carried out once or twice before you would have to re-new the whole section. Flanges which utilise a weldable gasket overcome these problems as even though maintenance access is required (usually every two years or in the event of a breakdown), the joint can be broken (using a large grinder), the two gasket faces re-machined (usually in position - which contributes considerably to the cost), re-aligned and welded. Apart from a bit of NDT (DP / MPI), thats it - job done.


Hope this answers your question.

Justyn.

Thanks Justyn,

okay, I see where you're coming from. Surely though the flanges could only be faced a few times before these would have to be replaced also? Especially if there has been any internal corrosion or pitting of the flange surfaces.

It is difficult to see from the picture you have attached what type the flange faces are but I'm guessing at a raised face (rather than an RTJ)?

Incidently, where is that flange?

Cheers,

A

quote:

Surely though the flanges could only be faced a few times before these would have to be replaced also?

Ah, but this is the clever bit, each time the flange is split and machined, your basically not taking much more off than the actual weld, which enables them to be split maybe a dozen times. The actual mating faces should in theory need no machining. Compare to a pipe weld which in reality should,nt be completed at the same location more than maybe twice, before the HAZ local to the butt suffers.

The flange in question is off a reactor (Hydrogen - hence the safety reason).

Justyn.

Justyn,

would you say there's no chance of the tip falling off then....??

Historically the flare has always gone out whenever there's been a strong (40 knots plus) wind coming from the North, in the opposite direction from what the pics show, possibly due to the tip being fitted at an angle. As to why it was fitted at an angle I have no idea, it's always been like that, and I've only been here 3 years (shit, has it really been that long!!) The flare over on the North Cormorant, where I was for 6 years before moving, was fitted vertically...

But that's not the end of the history.....
The flare boom used to look like this..........

I've had a dig about the network but couldn't find the picture that showed the split in the boom itself, but before they repaired the boom it looked like this.......

Oh, and the tip has also been replaced, year before last I might add, like this.....


If you look closely at the first pics at the start of this thread you can see a 'clamp' on the top section of the boom, this was deemed a permanent repair......

As for the tip/basket, well, it's definitely split.......

Question is, how long will it last.......over to you Justyn.....

Cheers,
Ali

Ali,

Actual construction of flare tips are outside my area, sorry. I’m familiar with high pressure piping systems up to 450Bar rating, as well as furnace and cryogenic piping including oxygen systems. Historically for furnace or other piping which is operating at extreme temperatures, we have always used either inconel 625, other forms of chrome moly and even high temperature stainless steels such as gr 310, hence my first post.

Knowing how petrochemical companies operate and in particular on-shore refineries (80% of our skid fabrication work ends up in a refinery somewhere in the world), the level of detail and engineering is extremely high. I would have thought that something like a flare tip would have a design life exceeding 5 yrs, so your safe for a while.

Justyn.

quote:

Originally posted by Justyn:
Ali,
Knowing how petrochemical companies operate the level of detail and engineering is extremely high. I would have thought that something like a flare tip would have a design life exceeding 5 yrs, so your safe for a while.
Justyn.

Cheers Justyn,

I would have thought/expected high engineering standards too, unfortunately these places are now showing their age, and lack of investment!
Also, when you see the shortcuts or cost cutting that goes on, just to reach targets, and prove places like this are still profitable and worth the investment....it's a worry....

Like you say, something like a flare tip should be designed for a working life of at least 5 years.......so why after two has it failed......

This is but one example though, it's not uncommon for us to receive pumps, recently back from on-shore refurbishment, for the bearings/seals to fail. We've had spool after spool that's come out and won't fit!! There's a fire pump on here that's started more fires than it's put out, seriously!! I could go on......

And no, it's not just because I'm stuck out here and not going home today as planned, got that confirmed half an hour ago - all flights cancelled......

Cormorant Alpha strikes again I guess!!

Cheers,
Ali

Ok, so maybe I'm a bit pissed off, but surely that's allowed.......

Getting home tomorrow will be all the better though won't it.

A

quote:

Originally posted by TheRedHerring:
Getting home tomorrow will be all the better though won't it.
A

That's assuming I make it off tomorrow......

okay.........

when you get home it will seem all the better won't it?!

The saga contines this morning......
...not the one about me getting off this rusty bucket as that shouldn't be a problem, the weather's calmed down, and yes Red you are right it will feel all the better I just wasn't in the mood yesterday sorry.

No, this morning we can clearly see a rather large HOLE, about the size of a dinner plate on the neck of the flare tip, just below the basket.....which wasn't there before!!!
I won't have the chance to take any pics, but believe me it looks bad.....

What was that you were saying about high engineering standards and a 5 year life Justyn.....

Anyhoo, I'm not going to worry about it for another two weeks while I'm at home, decorating.....

Cheers,
Ali