Got called to a prawn (shrimp to some) trawler.
Exhaust flex connection on one of the Cats split and no time to get another in, darks of the moon etc. Split was in the first valley next to the flange. Bridged from the flange to the next corro peak with 309.
Holding for now but no guarantee given.
Impressive. Any back purge? Is this one of those deals where it only needs to hold for one day, and you become a hero?
I really would be interested to know how long it holds together.
No sense dying with unused welding rod, so light 'em up!
I used air, salt and five years of diesel soot for back purge.
I told them the correct solution is to replace it but they weren't prepared to wait in harbour two days to get one.
Just weld er up and we're outa here.
I'm interested to see how long it holds too, I'll update as information comes in.
NIcely done! Those flexi's can be pretty thin wall and melt away at the smallest hint of an arc in the area..
The weld(-bead) itself will probably last fine/indefinitely. Sugaring on the back won't be pretty but this is likely not a high pressure section (aka. manifold to turbo) or a very hot section, so stresses are relatively low and really only corrosion would be a (slow) problem for such a weld in an exhaust here.
I suspect it's likely the (thin-walled) flex section right next to the weld that will crack at some point as that's the area where the stresses from the vibrations as the engine runs peak.
But it may well take a surprisingly long amount of time for that to happen unless the flexi material itself has already been developing hairline cracks before the original fault.
Very Nice job, Coldman. It seems that you can get yourself into some interesting projects. Can you tell us what type of equipment you were using for that repair ?
@Arno
Agree 100% with what you say. Staino work hardens over time. The first fracture may be indicative of the condition of the whole lot in which case other fractures can happen at any time. Customer was informed. They said they have nine days left in the season after which they can replace. Right now they need to be out to sea.
@BillE
Dynasty 200DX on the peddle
Gas lense, #8 cup, 3/32" lanth 2%, sharp
1/16" 309 wire.
60amps on the dial.
Peddle pulsed, mashed when on the flange, backed right off on the corro, probably 10-20amps
Stopped often to allow cooling. Slow process but avoided blow thru. Had ten tungstens prepared, had to change often to keep a sharp point going otherwise the heat spreads to the next corragation.
Given the inability to get the crap off the inside or purge it looks a good job - I've had a few of these on boats & they are often kinda eaten / corroded / suffering a form of electrolytic damage & just won't weld - I often braze them of choice believing that it is slightly more forgiving in flexibility than weld as that flex pipe likes to fatigue crack over time -had one where the owner had me over some years fix it enough times it barely had any flex left in it - but it lasted long enough each time he was never unhappy & paid me rather than replace it despite my protests of it would work out better in the long run !
Nine days...... should have told them you wanted 1% of the haul, if it lasted all nine days. Definitely makes you a hero if it holds up.
Still impressed after hearing more details. You are hereby awarded 1 Attaboy.
No sense dying with unused welding rod, so light 'em up!
The morning after the repair I got called back - it had apparently failed in a test run the previous evening. On inspection, my repair was fine, the corro had split in two places on the bottom of the flex.
FC1.jpg (98.76 KiB) Viewed 1184 times
Again no time to replace, get her done now.
FC2.jpg (92.52 KiB) Viewed 1184 times
The vessel has been to sea and completed the 9 days trawling left in the season and has since returned. The flex joint repairs have held, no problems.
Apparently there are no plans to replace it any time soon ...
Coldman wrote:
Apparently there are no plans to replace it any time soon ...
i do hate those temporary now permanent fixes.
it may fail in months to come and they blame you for it, even tho it was a temp fix to last a few weeks.
A bunch of prawns and squid turned up at the shop.
Nothing for it but to stop work, get out the bbq and beers. Better than a poke in the eye with a burnt stick.
Sometimes life’s good.
Coldman wrote:A bunch of prawns and squid turned up at the shop.
Nothing for it but to stop work, get out the bbq and beers. Better than a poke in the eye with a burnt stick.
Sometimes life’s good.
Coldman: not only have you accomplished a great job, you have made some great friends. Life is good. Congrats.
Bill
