VOR Leg 3 Cape Town to Melbourne and the Great Land Down Under

[duncan (the other one)]

info on possible keel configs here

http://www.cariboni-italy.it/public/caritec/products/datasheets/CantingKeel.pdf

 

[Chasm]

Chasm you will be hung, dried and quartered by the Quotation Police here with that devil may care attitude to factual accuracy.

Can't have that! 320kg for the box itself, "close to half a ton of carbon" with the bulkheads.

can someone with a bit more knowledge explain why there's water ingress with the ram failure?

If I interpret the above comments correctly the head of the ram pivoting on the 'fixed' boat/hull end has failed.  Did it punch through / crack the keel box ?

Hmm...
The keel rams are from the ABN AMRO ONE design:


The attachment to the keel head is slightly different:


Here is a pic of the keel box from the Vestas repair:


My guess is that there is a seal between the head of the keel and the cylinder compartment. Either riding on the shaft or a bellow butted against the cylinder head. That seal got moved out of position or damaged when the fitting failed. 

Sequence should look something like this.
Cylinder head cracks -> Oil seal failure, dumping high pressure oil into the cylinder compartment until the system is empty
Cylinder shaft moving out of position -> Water seal damage, water intrusion into the cylinder compartment and from there into the boat.

When did they notice the problem? Moving the keel to starboard would be my guess, that is where there is most oil pressure on the cracked side.

 

[duncan (the other one)]

I reckon they have the first config in that datasheet I linked -- two double acting cylinders, which explains why cant still works in both directions due to the redundancy... difference looks like the top pivot is in a different spot (top of cylinder rather than center)?

Could be the seal-around-the-cylinder setup (longitudinal plates, #4) failed a little when the head cracked and misaligned the cylinder.  Note the seal failure wasn't catastrophic, just a 'bit' of water.

 

[Rushman]

I reckon they have the first config in that datasheet I linked -- two double acting cylinders, which explains why cant still works in both directions due to the redundancy.

Could be the seal-around-the-cylinder setup (if they use that) failed a little when the head cracked and misaligned the cylinder.  Note the seal failure wasn't catastrophic, just a 'bit' of water.

If the seal moved and allowed water into the wet box.... How did the water appear in the bilge? 

Mr "Fix It" looked to be taking the top off the wet box under water

 

[duncan (the other one)]

the wet box is, how do I say this, 'wet'.

The sides of the box have the rams entering, and are sealed with a circumferential bellows type thing. If they fail, water gets in the boat.

(aside -- if its bellows and not a seal, why did it fail?)

1:22 is water sloshing around outside the wet box, IMHO.

 

[Rushman]

the wet box is, how do I say this, 'wet'.

The sides of the box have the rams entering, and are sealed with a circumferential bellows type thing. If they fail, water gets in the boat.

(aside -- if its bellows and not a seal, why did it fail?)

1:22 is water sloshing around outside the wet box, IMHO.

Lots of water IMHO... The blue hose heading to the cockpit suggests they have the big bilge pumps engaged 

 

[rogerfal]

Mapfre is at the rip now doing 12.6 knts according to the AIS

Shortly to meet a ferry leaving the harbour.

Otherwise looking quiet.

 

[shanghaisailor]

No need to shout! 

Ha ha - just the way it cut and pasted from the VOR website - Happy Christmas by the way Mad

SS

 

[Fiji Bitter]

Speed has dropped to under 9 as they are going in 70 minutes after the maximum ebb tide 5.04 knots

I know you are a local, but are you sure about that tide? Where do you get that from, please?

 

[Fiji Bitter]

http://www.bom.gov.au/ntc/IDO59002/IDO59002_2017_VIC_TS001.pdf

We went through at 12 or 13 knots, but we went through on a flood tide.

Thanks hoppy, that makes it easy.

Been reading this: http://www.bom.gov.au/australia/tides/about/p4a-port-phillip.shtml  , and then I must have mixed things up. Never mind for now, but for the next boats this could be a factor.

 

[lighthouse keeper]

1110 pm Just watched Mapfre go past Point Lonsdale,  3 ebb tide didnt seem to slow her down at all guestimate 3-4 knots of outgoing flow. Wind was 16 knots gust to 20 knots  from the south via the dial at the lighthouse.Other that can only tell you their nav lights work lol  Dark night down here

 

[shaggybaxter]

Lots of water IMHO... The blue hose heading to the cockpit suggests they have the big bilge pumps engaged 

The head on my ram is external to the keel box. Around the extruding part of the  head is a large rubber gaiter as the first layer, with another separate inner waterproof membrane underneath that.

At high speed I reckon even a small leak would let a lot of water inside the boat.  

 

[SCANAS]

Dongfeng now on AIS doing 20knt!

 

[paps49]

That seems easy enough but where did the water come from?

Will the other identical boats suffer the same problem in the future?

Great Scott!!
That's exactly what I thought!

 

[paps49]

That must be stressful?

 

[jack_sparrow]

You are just saying that Jack because

e the likes of you and me are just as lazy

Ironically it was I who started Keel Fingate (using same VOR website), but which at the time I could not recall where it came from. So having tipped you into it, I probably owe you one.

 

[thengling]

the likes of you and me are just as lazy

Could be, most of us are well to "loo"-ward of the action, which is why we are here. (notice I said "most")

 

[jack_sparrow]

Here you go Jack

Thanks stief....mmm ..cogs moving.. watch this space.

 

[rogerfal]

Interesting finish as the Mapsters get their final workout short gybing up the harbour in the dark....

 

[mdeh]

Interesting finish as the Mapsters get their final workout short gybing up the harbour in the dark....

6 knots blowing... ouch!!! It's going to be a long night.

Maybe I should take that back... Windyty.... shows a lot different.