LifeSaving Davits and Cranes

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JK
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LifeSaving Davits and Cranes

Postby JK » Mon Nov 03, 2014 8:59 am

One falls under the lifesaving equipment regulations in Canada, the other doesn't.

The completed installation is subjected to tests in accordance with SCHEDULE IX of the Canada Shipping Act’s Life Saving Equipment Regulations (See Referenced Sections):

• Static Load Test of davit arms at full outreach = 2.2 x S.W.L. (Ref.: Section 8 ).
8. In the case of all davits made of cast steel or of wrought steel or
other material fabricated by a welding process, each davit at full outreach
shall be capable of withstanding a static load test of not less
than 2.2 times that part of the working load supported by each arm.

• Lowering Test = 1.1 x Maximum Loaded Weight of the craft (Ref.: Section 13).
13. (1) Where lifeboats and life rafts must be capable of being
lowered fully loaded, each pair of davits and each launching device,
including winches and brakes where fitted, shall be capable of safely
lowering the lifeboat or life raft loaded with the required equipment
and a distributed weight equal to the number of persons for which it
measures plus 10 per cent of the total load, including blocks and falls.


When we last built davits, they underwent tests ashore of 2.2 x SWL to ensure that there would be no failure.
Then when they went on the ship, there was a static load test with weights hung from the davit head to ensure that the foundations were designed correctly. Welds were NDT and structure examined for deformation.
Then the lowering test ensured that the brakes and running gear were capable of stopping and holding a boat.


Ok now, cranes, tested at 1.25 safe working load in shop test and on the ship subjected to a 1.25 x SWL test with boom at full extension at 90*. Same deal, all foundation checked.

Now, we get into the barges, workboats ect...what do they fall under. I guess to be on the safe side you would follow the lifesaving regs.

I have been recently told that the drop test is acceptable on lifesaving davits because if they can take that without failing, then they don't need the 2.2 static test. I was rather shocked...apparently this is accepted outside Canada.
Can someone enlighten me on that little detail? I was more then surprised to be told that.

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JK
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Re: LifeSaving Davits and Cranes

Postby JK » Mon Nov 03, 2014 9:07 am

and, 75 kg is the weight each person is considered to be under regs.

Is there an average height used as a consideration when designing elements on a ship?

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JollyJack
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Re: LifeSaving Davits and Cranes

Postby JollyJack » Tue Nov 04, 2014 10:22 am

Have a look at this. Barges, work boats etc are "vessels" under CSA 2001 vis:

“vessel”

“vessel” means a boat, ship or craft designed, used or capable of being used solely or partly for navigation in, on, through or immediately above water, without regard to method or lack of propulsion, and includes such a vessel that is under construction. It does not include a floating object of a prescribed class.



and from Cargo, Fumigation and Tackle Regulations (SOR/2007-128)


http://laws-lois.justice.gc.ca/eng/regu ... html#h-206
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JK
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Re: LifeSaving Davits and Cranes

Postby JK » Tue Nov 04, 2014 2:20 pm

Thanks, those types of boats always seem to baffle me plus the regs always makes me feel like a dolt! But it is still fuzzy what the da its have to meet. I see intense reading in the near future.
My type of rules would be black or white, not 50 Shades of Gray.

Hey, I was serious about the height after reading about the exemption the cruise ships have for carrying so many people. The would have to tier them, or are they in rows?
Can you imagine that many people seasick?.
We were talking about it today, a rescue ship wouldn't be able to take people out of the boats, they wouldn't have the space, they'd have to put a line on them and tow. Pleasant prospect.

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Big Pete
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Re: LifeSaving Davits and Cranes

Postby Big Pete » Wed Nov 05, 2014 12:55 am

I was involved in changing out all the Lifeboats on a couple of Oil Rigs in the North Sea. Carried the new ones out and the old ones back on the pSV I am sailing on.
With the new assumptions on average weight, the numerical capacity of the Life Boats had been reduced to reflect the increased average weight. As a result the Rigs had to be operated with reduced crews until the Boats had been replaced with ones of larger capacity.
The Rig owners did not want to replace the Davits, so they had new Boats designed and built using light weight materials so that the loaded weight of the Boats, using the new average weight figures was within the Davit Capacity, while they had the capacity to carry the original number of people allowing for the greater average weights.

B.P.
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JK
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Re: LifeSaving Davits and Cranes

Postby JK » Sun Nov 23, 2014 6:44 am

Yes, we did the same thing for workboats. The ship was allowed to grow in weight through the years and Ops didn't want to address that, but wanted equipment to deal with every contingency. Weight and draft be dammed and hell we don't need more potable water if it raises other issues, like a weight survey.
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Re: LifeSaving Davits and Cranes

Postby JollyJack » Mon Nov 24, 2014 7:53 pm

The Regulations don't apply to Government ships, you can die legally.
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JK
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Re: LifeSaving Davits and Cranes

Postby JK » Fri Nov 28, 2014 6:53 am

I wonder how many hours, days, weeks I have wasted trying to define things from the CSA. Blech :evil:


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