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Dry Dock heavy lifts and some additional information from the Home Built Gantry Thread

Brent H

Ultra Member
@YYCHM Here is some additional information and pictures for you:

Large marine vessels have rules and regulations and inspection societies that they fall under (Think Insurance reasons) . Most know Lloyds and then there are many other like DNV, ABS and Canada is TCMS. The ships are put into classifications depending on the type of journey they typically have , near coastal, inland waters, international etc etc and depending on the classification they have to be inspected by the governing bodies so they are permitted to operate/ be insured. Same as myself, I had to write exams, study a whole lot of stuff, intern like a doctor and pass the engibar like a lawyer - all without the great pay of course....

We have to dry dock 2 times every 5 years for inspections to keep our inspections valid. It is more of a compliance than a necessity and it also feeds the public cash flow by keeping the ship yards in business...as sometime poor the business done to the ship is...


At this docking we were in for tail shaft and propeller inspections, new bow thruster, hull paint and a bunch of other things. Seam welding on the hull - typical stuff other than the bow thruster replacement.

DSCN0013.JPG

DSCN0183.JPG

All the green paint in the photo above is marking seams that need grind and weld. The weld has to be proud of the surface about 1/4" and span the distance between the plates. This is so the weld itself does not wear through and create a weak point. I was on the cherry picker laying out a lot of green that first couple days as our last docking the paint system fell off and the ice could get at the welds and wear them down - sounds strange but it happens - We got the welds fixed and the hull sand blasted and re-coated and then 6 months later that paint fell off...ugh!..... the hole is for the new thruster unit. Hull thickness is 1.5" in that area. I made my centre for the rotary table out of a chunk of scrap from this area.

DSCN0208.JPG

Lots of fun but dangerous as all get out - LOL

Funny thing is- if you guys have a well equipped shop and maintain your machines - you probably have better tools than these guys...sad but true...dollars just feed the wealthy owners......
 

DavidR8

Scrap maker
Administrator
Moderator
Premium Member
Is that dry docked Brent?
I live relatively close to the graving dock at CFB Esquimalt. They sometimes have Coast Guard and other government vessels in for work.
Massive cranes there!
 
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Brent H

Ultra Member
Yep @David_R8 - Newfoundland

pretty cool yard, had a heavy synchro lift that brings the ship up to a railroad system. A CAT D8 pulls the ship onto the railroad and they can then move the ship left or straight ahead into a position - pretty cool. Three large ships or a bunch of smalls.

@Janger : yes controllable pitch props - like an air craft. Total prop diameter is about 10 feet (3 ish meters)

@RobinHood : areas supported by the sawhorses are the shaft sleeves - bearing bronze shrunk fit onto the shaft. The bearing sleeves ride in Throdon bushings - the bushing is a composite plastic type material. Has slots for cooling and clearing debris like sand, mud etc. Kept clean and lubbed with water pressure from pumps. In between the bushings is the regular shaft. As it would corrode quickly and undermine the bushings, it is sealed with a coating similar to a truck spray in bed liner. On top of that is a coating of anti fouling paint.

props are bolted onto the shaft hub. Shaft is hollow cored and hydraulic fluid is pumped down to move a large piston that rotates the props via eccentric connection to the blades. Movement is fed back to a control box through a pipe that also carries return hydraulic fluid.

props are made of Cunial which is a copper nickel aluminum alloy special design for ice breaking strength.
 

RobinHood

Ultra Member
Premium Member
Thanks for the info on how the bearings work. The prop control is similar to some systems on airplanes, just a few tons heavier...
 

Brent H

Ultra Member
@YYCHM : we are the ship that CAN ...LOL we were born in Delta BC in 1985 and did the Panama Canal trip back to Ontario (I was not yet in the Guard but close). Since I have been working on here we have done patrols all over Sova Scotia, dry dock at Shelburne, dry dock at St John's NFL and also at Les Mechine Quebec and the ship has been all the way up into the Arctic to Greenland, back through the lower Arctic to the mouth of Hudson Bay and then all down the coast of Labrador, St Lawrence Sea Way and through out all the Great Lakes. Probably one if not the only ship that can boast that. A few others have done a bit of the lakes and more Arctic time but hey, we were not really expected to do all that - LOL We have one more docking the end of this summer and that is my last one :)
 

DPittman

Ultra Member
Premium Member
So one of the things I like about this forum is the broad range of topics that are discussed. I'd never look up that sort of information on my own but because it is of interest to other metal hobbyists, I too have the opportunity to learn about it. Thanks.
 

YYCHM

(Craig)
Premium Member
If you were in St John's in 2016. I think I have a picture of the ship in the harbour. You have a crane on the aft end of the ship correct? St John's was our final destination after a 3 week motoring tour starting from Fredericton NB.
 

Hacker

Super User
I was there in the fall of 2016 as well. Sailing into the harbour in St. John's is really interesting. I was on board a 3500 passenger cruise ship and that opening sure looks small as you are sailing into it. St. John's is one of the best ports that I have been to. Great people and had a wonderful time there.
I never knew that a vessel that large would have a variable pitch prop. Thanks for posting that Brent very interesting.
 
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Tom O

Ultra Member
Is that dry docked Brent?
I live relatively close to the graving dock at CFB Esquimalt. They sometimes have Coast Guard and other government vessels in for work.
Massive cranes there!

My Dad machined at the DND dockyard for 30 some odd years working on ships and subs.
 

Hacker

Super User
Funny thing is- if you guys have a well equipped shop and maintain your machines - you probably have better tools than these guys...sad but true...dollars just feed the wealthy owners......

Interesting statement, I worked with a couple of millwrights that got their start in shipyards. If anything was left unattended for more then five minutes and they could get it into their lunch bucket or the trunk of their car without anyone seeing them that item would never be seen again. That might be why the tools in shipyards were so poor so they weren't worth stealing. LOL
 

Brent H

Ultra Member
@Hacker : we routinely supply fresh tools to the yards and find out later (once we have left) that we made a donation..... :rolleyes: Some are better than others. I would expect that some of the money fed into the bigger docks maybe has gone into some re-tooling? Hard to say. I find it disappointing at times because the new tech will also attract the young people and we need them excited about building and fixing and maintaining things. To walk into a shop and see milling machines older than mine and lathes in various stages of decay is disheartening. Shops like these wear out tools - its understood, but then update and keep your people interested in progress. It is great skill set to manually machine and learn to cut and weld and pipe fit etc etc but ya gotta have a CNC and water jet and things that will keep the youth interested.

In my early times there was some seriously talented people in the base shops from millwrights to designers and naval architects. It has slowly fallen off....some trades still get a few that shine but the less romantic the job, the less enthusiasm and professionalism.....anyway rant over .. LOL

glad you guys are enjoying the post - I will add a few more pics and things tomorrow - I will add a couple scans of our original build from Delta BC (@David_R8 will be excited) some serious lifts going on :)
 

Dusty

(Bill)
Premium Member
@Brent H, over the years I've had a couple of neighbors who borrowed tools then had to go chase them down (borrow them back).

Come to think of it haven't we all experienced this, at least the guys who could afford tool sales. LOL
 

historicalarms

Ultra Member
@Hacker : we routinely supply fresh tools to the yards and find out later (once we have left) that we made a donation..... :rolleyes: Some are better than others. I would expect that some of the money fed into the bigger docks maybe has gone into some re-tooling? Hard to say. I find it disappointing at times because the new tech will also attract the young people and we need them excited about building and fixing and maintaining things. To walk into a shop and see milling machines older than mine and lathes in various stages of decay is disheartening. Shops like these wear out tools - its understood, but then update and keep your people interested in progress. It is great skill set to manually machine and learn to cut and weld and pipe fit etc etc but ya gotta have a CNC and water jet and things that will keep the youth interested.

In my early times there was some seriously talented people in the base shops from millwrights to designers and naval architects. It has slowly fallen off....some trades still get a few that shine but the less romantic the job, the less enthusiasm and professionalism.....anyway rant over .. LOL

glad you guys are enjoying the post - I will add a few more pics and things tomorrow - I will add a couple scans of our original build from Delta BC (@David_R8 will be excited) some serious lifts going on :)

Buddy of mine who owned a machine shop ( building with a bunch of manual lathes/mills & one CNC mill) in Cowtown often lamented to me that in the high demand time for machining done ( high one-off oilfield demand), when advertising for new employee's, he would receive 20 resume's for people wanting CNC jobs for every one that felt qualified for manual machine work.
 

Hacker

Super User
@Hacker : we routinely supply fresh tools to the yards and find out later (once we have left) that we made a donation..... :rolleyes: Some are better than others. I would expect that some of the money fed into the bigger docks maybe has gone into some re-tooling? Hard to say. I find it disappointing at times because the new tech will also attract the young people and we need them excited about building and fixing and maintaining things. To walk into a shop and see milling machines older than mine and lathes in various stages of decay is disheartening. Shops like these wear out tools - its understood, but then update and keep your people interested in progress. It is great skill set to manually machine and learn to cut and weld and pipe fit etc etc but ya gotta have a CNC and water jet and things that will keep the youth interested.

In my early times there was some seriously talented people in the base shops from millwrights to designers and naval architects. It has slowly fallen off....some trades still get a few that shine but the less romantic the job, the less enthusiasm and professionalism.....anyway rant over .. LOL

glad you guys are enjoying the post - I will add a few more pics and things tomorrow - I will add a couple scans of our original build from Delta BC (@David_R8 will be excited) some serious lifts going on :)
I get where you are coming from now, you are referring to machines and tooling for them. I can see where that would be disheartening, management that does not look after or upgrade their equipment usually treats employees the same way.
Having CNC and water jet also makes you competitive saving time and material. That equipment takes a lot of the repetitive tasks and dirty work out of job.
 

Brent H

Ultra Member
@historicalarms, I can agree with that....The CNC or other "computer work" would at least get the people looking. Last dry dock we were at the "machine shop" was a quonset hut style metal building with a dirt floor and maybe 8 or 10 old fluorescent lamps above some work benches and a few mills and lathes that the owners had picked up cheap at auction and repainted. It was pretty dreary. The old Port Weller Dry Dock looked like something out of a Saw horror movie. Not a place that exuded safe working practices or career advancement - LOL
 

Hacker

Super User
It is pretty bad when you have to supply the machine shop with tools so they can complete the work. It would be hard to attract talented people let alone retain them in those kind of conditions. I imagine working there would be frustrating and demoralizing.
 
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