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hey fella's, basicly i'm a boilermaker by trade, have worked on quite a few high profile jobs, the new docklands ferris wheel is one, repairs on the MCG retractable roof, desalination plant and working in power station boilers, after abit of interested in what i do in the wasteland i thought i might post up a few pic's on what i'm doing at the moment.

basicly i'm "spooling" and welding pipe for ESSO, an offshore gas company with 20 odd rig's in the bass strait, the pipe's on these rig's are replaced every 10 year's for safety reasons, so we're making up some new pipe, we welding with TIG for the smaller stuff under 120mm nominal bore (inside diameter of the pipe) and under 8mm wall thickness, anything bigger and we use a special MIG machine made by lincoln weld called an STT (surface tension transfer), basically it pulses the amperage from a lower background setting, to a high peak, the idea being to be able to weld faster then with a stick welder (which is the old hat way of welding big pipe) but with much lower heat input then a MIG as well as almost zero spatter, excesive heat input will cook the aditive's out of the steel making it brittle and prone to cracking, so weld procedure's are strictly adhered to.

these baby's are worth 14k each without a wire feed unit

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and another 3k per wire feed

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this is an STT weld on the 300mm pipe, the weld's on the 80mm branch are done with TIG

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this is the machine we use for TIG, they made by fronius and are worth around 9k each, they do standard and pulse MIG (they pulse from full power to nothing, unlike the STT which pulses from full power to background power, so these are no good for the pipe weld's) TIG welding and stick, and you need to be able to fly an F16 fighter jet to set them up, over 100 separably adjustable parameter's

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this is a spool we knocked up in about 8 hours (tacking, not welding), this one bolt's to the header of a compressor, the upright section's with the flanges are 200mm nominal bore pipe with a 12.7mm wall, these are not allowed to be drifted into place when being installed due to vibration issue which can damage the 5 million dollar compressor, so the tolerance once welded has to be spot on, each weld shrink's around 2-2.5mm when welded depending on the root gap which has to be taken into account during fabrication, the section at the front with 6 weld's will shrink 14mm after welding, talking about those flanges, the clamping face is 110mm thick 1.25% cro-mo steel, each flange has 20 38mm high tensile bolts tightened to 1200 NM each, clamping force is 16 tones per join.

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this is what we use to cut the pipe to length and bevel then at the same time, the procedure for this job is a 25 degree bevel on each side of the weld

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a few completed spool ready to weld

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as the pipe's need to hold 1700 PSI of pressure, and the content's is natural gas making it incredibly dangerous if a weld fails while the gas rig is in operation each weld is gammer ray tested and X ray tested to detect imperfection's in the weld metal such as porosity, inclusions and lack of fusion, each test cost's around $1000, we weld these on a "butt rate" which means we get paid per weld, with any repair's getting completed in our own time and we cover the cost of the extra gammer and x ray, we get $120 per weld, and a good welder can do a weld in 35 minutes, good welder's get in 15 a day

There's a good chance that we supplied the pipe and fittings for this.

I'm a bit surprised at the unprotected RF's on the weld necks, you guys must be good at keeping things separated (unlike some peanuts out there).

It's good to see you're proud of your work, well done.

That machine, which I assume is an oxy torch for pipes looks AWESOME!

Everything else is pretty darn cool, especially knowing how much you're going to shrink a pipe by!

dead on thumbsup.gif just an oxy with a swivel head for the bevel and the chain and gear arrangement to keep in traveling around the pipe, worth around 2k it's amazing how much some of these thing's cost

There's a good chance that we supplied the pipe and fittings for this.

I'm a bit surprised at the unprotected RF's on the weld necks, you guys must be good at keeping things separated (unlike some peanuts out there).

It's good to see you're proud of your work, well done.

if that's the case then tell whoever machines the bloody things we only want 1mm landing on the flanges, grinding to back is a pain in the ass

if that's the case then tell whoever machines the bloody things we only want 1mm landing on the flanges, grinding to back is a pain in the ass

As we're a distributor, we have to take what's given to us. Special requests bump up the costs somewhat and it's not something that our customers wish to bear.

What this means unfortunately is that you, the fabricator, have to use your magic touch to make things right.

The only people who get what they want is Woodside, but believe me, they pay for it. Just one of the fittings (header tank with 4 test rings) that passed through my projects warehouse last week cost them over $180k, including air freight and testing.

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