alaskan steel men question

[caterpillar028]

i am sure i was not the only one watching this program my question is

there was a boat they went out and welded with a crack in the hull they hammered wooden wedges into the crack to stop the leak they just seemed to weld over the crack wood and all

would this not make getting a good weld very hard i am sure we have all tried welding dirty metal with a stick welder it does work but the weld penetration wont be great

also what type of amps would it take to do this job does the fact that theres water on one side of the metal not act like a big heat sink

some one with more experience will know this of the top of there head

 

[penfold]

A proper repair would involve cutting out the cracked metal and welding in new metal, possibly with a doubler plate added if necessary to prevent recurrence.

 

[nickk]

i got away with welding splits in some trays which had water pushing up the underside of the cracks ,in a series of short stitches,the work needed to remove them from the m/c to do a proper job was out of the question & it wasn't safety critical,the m/c were subject to vibration /impact & lasted several more years.

 

[dannyp]

with emergency repairs its not usually possible to do things the ideal way.

if I was on a boat with a hole in it welding over wood wouldn't bother me. once you've stopped the wet getting in you could always put a plate over the whole lot and get a nicer weld round that if possible. then deal with it and do a proper repair in dock

 

[brightspark]

with emergency repairs its not usually possible to do things the ideal way.

if I was on a boat with a hole in it welding over wood wouldn't bother me. once you've stopped the wet getting in you could always put a plate over the whole lot and get a nicer weld round that if possible. then deal with it and do a proper repair in dock

well its certainly better than sinking no matter how u do it

 

[dannyp]

I was getting this vision of someone with a 9" saying " I'll just cut this out for a nice square patch "

 

[madkayaker]

I would guess there using very big sets passing several hundred amps so a bit of rusty steel or wood is not going to stop the. For long! I also bet if your on a boat taking in water your going to want to fill the whole in pdq and stay dry.

 

[Wedg1e]

with emergency repairs its not usually possible to do things the ideal way.

if I was on a boat with a hole in it welding over wood wouldn't bother me. once you've stopped the wet getting in you could always put a plate over the whole lot and get a nicer weld round that if possible. then deal with it and do a proper repair in dock

A few months before she was decommissioned, the last Ark Royal headed off from Pompey on some mission or other (probably delivering a new Bentley to the Governor of Barbados or whatever). Shortly afterwards she turned around and came back, the crew apparently unable to get more than 4 knots out of her. It transpired that she'd been aground, split the hull and had a 4 foot square patch welded on. Unfortunately the weld was down to BAe Systems standards () and the patch peeled back, forcing water into the hull and slowing the old bus down...

...or so I'm told

 

[dannyp]

bet there were some interesting words said about that

 

[snowcat]

I used to carry out emergency works to vessels (around the 3000T size) the biggest problem with water side repairs is closing the hole, especially as the water turns to steam with the heat, Most water side repairs are classed as temporary and the marine servayor and the captain have the final word. Iv known crews however sail on "temporary repairs" for years however typically a timescale is put on the log by the insurer to how long they will allow the vessel to continue to work before a proper repair can be made.

doubling plates are frowned on in the Marine world, the cause Rot between the layers and make visual inspections imposible, If a repair is seroius its a matter of cutting and replaceing, plate has to be certified, or tested.

Virtually all commercial vessel repairs are carried out with a servayor being present.

That Alaskan steel men program is just plain daft, watched about 20 minutes of the first episode, Its absolute hype for TV. there's nothing fun glamours or exciting about being wedged in a ballast tank on a 20C day nee deep in mud repairing webs on some old Russian crate.

 

[caterpillar028]

i presumed it was just a temp repair

i was more curious about welding with water on one side
if the hull is say 12mm (just for talks sake) saying you did multiple passes with a 3.2 at 110 amp that would normally weld ok. but what if there was salt water(or any type liquid) on the other side what type of amps would be required

 

[snowcat]

The difference is nominal. If anything as your building with stringers to fill a gap the amps are slightly less, as I said closeing the gap is the sod, all the vessels I worked on we're doubled skinned so you were always internal between the hull and the inside of the ballets tank, which are a network of crawl spaces making the job even harder.

 

[Wedg1e]

bet there were some interesting words said about that

The current darlings of the Royal Navy, the Type 45 destroyers, are known as 'dockyard windbreaks' owing to the amount of time they spend tied-up at Middle Slip covered in scaffolding.
I hear Daring has bent a shaft (propshaft I assume), the wags are saying she'll be scrapped as a result and if previous experience is anything to go by, that might not prove to be wrong...

 

[Wedg1e]

Most water side repairs are classed as temporary and the marine servayor and the captain have the final word. Iv known crews however sail on "temporary repairs" for years however typically a timescale is put on the log by the insurer to how long they will allow the vessel to continue to work before a proper repair can be made.

When one of the 45's had its hull split by a tug, they patched it with scaffolding boards and concrete. As it was just before Navy Days and they only had a couple of 45s to show off, they moored her with the damage away from the jetty so the public couldn't see it... but anyone passing on a cross-channel boat could

I should say 'allegedly'

 

[penfold]

The current darlings of the Royal Navy, the Type 45 destroyers, are known as 'dockyard windbreaks' owing to the amount of time they spend tied-up at Middle Slip covered in scaffolding.
I hear Daring has bent a shaft (propshaft I assume), the wags are saying she'll be scrapped as a result and if previous experience is anything to go by, that might not prove to be wrong...

That is rather unlikely; T45 ~£1bn >>> Tail shaft, even a gucci RN one, <£10m, although I'd be interested in how it got bent, assuming it isn't just idle bollards spun by the ignorant.

 

[daleyd]

I believe the t45s have electric propulsion and therefore have the motors sited close the the back of the ship, resulting in quite short shaft lengths, as opposed to older designs with the GT s in the centre of the ship and long shaft lengths.

Also, a 4 ft plate coming adrift wouldn't have slowed the ark down much, she had 4 Olympus gas turbines and was no slouch ( certainly left the Lancaster in her wake on one exercise I remember).

We did have a propellor fall of as we left the sheds in Plymouth once after a dry dock period - quick turn around and back in (hms Argyll)!

 

[Wedg1e]

That is rather unlikely; T45 ~£1bn >>> Tail shaft, even a gucci RN one, <£10m, although I'd be interested in how it got bent, assuming it isn't just idle bollards spun by the ignorant.

Well possibly; I dunno where she is but I haven't seen her in port this week - Duncan is scaffolded and Dauntless is sat there looking forlorn.
Bouncing the prop off something hard would be my guess (happened to one of the RFA's IIRC; I think it was one of a string of things that led to her being scrapped).
Given various recent farcical decisions by the powers that be.... [edited for political correctness ]

The Navy had to shell out 'an undisclosed sum' to buy back a comms cabinet from the Turkish scrapyard that has the Ark to replace one damaged in a fire on Illustrious (due to dry-dock sometime next week if the dock is fixed by then).
This isn't top secret by the way, it was all over the papers a week or two back.

There's also the small matter of the contract they had that originally specified 18 T45s, was reduced to 12 and further reduced to 6... but the builders held them to the full contract price.
Why in God's name did they not just build the hulls anyway (would have kept the Scots/ Poles in work for a while) and flog them to the highest bidder, at least they'd have got something back...?

 

[Wedg1e]

I believe the t45s have electric propulsion and therefore have the motors sited close the the back of the ship, resulting in quite short shaft lengths, as opposed to older designs with the GT s in the centre of the ship and long shaft lengths.

Also, a 4 ft plate coming adrift wouldn't have slowed the ark down much, she had 4 Olympus gas turbines and was no slouch ( certainly left the Lancaster in her wake on one exercise I remember).

Again, just repeating what I was told... but I'm sure that irrespective of whether it would slow the ship down, there would have been an alarm ringing somewhere...

 

[penfold]

They are indeed powered by electrickery; as for the mysteries of the Great British Military Procurement Disease, your guess is as good as mine. A cynic might say that BAE routinely bribe MoD personnel, a realist might just conclude that a MoD drone who's in post for at most 3 years is easily duped by a BAE salesman.

 

[daleyd]

Ah BAE, broken and expensive was one less favourable name they used to get called.

Again, just repeating what I was told... but I'm sure that irrespective of whether it would slow the ship down, there would have been an alarm ringing somewhere..

LOL yeah, the alarm was probably some stoker complaining when his steaming bats got wet!

With reference to the cost, they certainly went well over budget but don't believe everything you read in the papers - the original 12 were planned but never actually ordered.