Ice class?

[Deleted]

i have heard about this thing called the ''Ice class''
what is this because i have heard they did this to the queen of the north.

[Balfour]

I'm no expert, but I believe Ice class is given to ships that has a hull capable of breaking through Ice. I heard somewhere that the Coastals have a degree of Ice Class to deal with the amount of logs in the coastal waters here.

I'm pretty sure there's someone on this forum who knows more than I do...

[Deleted]

I have heard about that and i have heard about the spirits having that aswell.

[kerryssi]

I have never heard of an " ice class ". What would they need one for on this coast anyway? The Hound Dog has a thick hull because it is an ex river boat from Quebec. No logs would bother the hull of any of the ferries. The danger lies in logs going under the hull and impacting the propulsion system. A hull designed to resist ice would be very expensive and a total waste here.
On the subject of ice. The customs office on Pender Island used to be shut down every winter. The boaters kept petitioning for it to be kept open year round. Ottawa kept refusing due to the thick ice we got here every year which closed the harbour and prevented boats from moving???

[Deleted]

Yes ice class is with mostly i have heard northern vessels like the QOTN.

[Mill Bay]

O.k. troops, time to go back to school.

From The Nautical Institute:

Ice Operations

"Increasingly, modern merchant vessels are spending more time transiting Polar waters. This has been driven in part by the growth in the high latitude tourist trade, the increased deployment of Russian oil and gas from Northern ports, and new routes being made accessible due to new technologies and changing weather patterns.

Operating in Polar waters and ice comes with inherent risks and demands highly developed skills, procedures and equipment. The following documents concerning the operation of commercial ships in ice, have either been published by The Nautical Institute, or have been referred to by such publications. "

www.nautinst.org/info/Ice.htm

www.nautinst.org/ice/docs/iceClass_Duggal%20.pdf

[Guest 101]

The question is do we need Ice Classed Hulls on are "local" vessels?

If you read the above links - what it means in general terms - is that frames are closer together, and plates are thicker - so they can withstand the pressure.

Transfer that to the coast - and look at the speed we are claiming each of our "local" vessels is doing. With a log strike - on a "normal" hull - at speed this could cause problems - but on an ice classed hull - it should not. {in theory}

The Coastal have "ice class" around the shaft - to guard against a major log strike.

[Neil]

May 31, 2008 9:49:31 GMT -8 @Guest 101 said:

Transfer that to the coast - and look at the speed we are claiming each of our "local" vessels is doing.

Of course, they're probably lying about the 'claimed' speed, right, Cascade?

May 31, 2008 9:49:31 GMT -8 @Guest 101 said:

With a log strike - on a "normal" hull - at speed this could cause problems - but on an ice classed hull - it should not. {in theory}

Wrong. Ferries have been hitting logs 'at speed' for decades- without ice strengthened hulls.

[Guest 101]

Neil -

When they built most of these vessel - 30 odd years ago - there Hull's were very close to Ice Class then - which is one of the problems we currently have - and that is the weight of the vessel and the amount of power to push her through the water - which equals fuel consumption - and that means higher fares....

As for speed - well they do claim things like 18knts...still can't see it myself...but then your the expert

[kerryssi]

Some newer vessels, such as the Cumberland are only allowed out in the gulf in mid summer due to the light hull construction.
I can't think of any car carrying ferry whose hull would be damaged by a log.
Here are some speeds of smaller ferries. I got this when I was working on schedule proposals for the SGI

Bowen............14 ( all speeds are in knots and with a clean hull)
Howe Sound.......10.5
Kahloke.....10
Klitsa......10
Mayne............14
North Island Princess..........10
Powel River..............14
Quadra..........12
Capilano................14
Cumberland.................14
Nanaimo............16
Esquimalt...................19
New Westminster.........21
Saanich...................19
Vancouver....................19
Quinitsa...............12
Quinsam....................12
Tenaka..............12

[Kam]

If you look back in the Coastal Renaissance thread someplace this was answered bay Markus. Basically the rudders and propellers are designed to the highest ice class to help withstand log strikes. The rest of the hull is not rated as ice class. I think he said ice class was sort of an in accurate term, but no one has developed a standard for a "log strike class" yet

[Neil]

May 31, 2008 10:13:24 GMT -8 @Guest 101 said:

When they built most of these vessel - 30 odd years ago - there Hull's were very close to Ice Class then - which is one of the problems we currently have - and that is the weight of the vessel and the amount of power to push her through the water - which equals fuel consumption - and that means higher fares....

BC Ferries' vessels were conventional hulled- we found out how much more expensive an ice class boat was to run when they bought the Sunshine Coast Queen, and it was only classified as a semi ice breaker.

May 31, 2008 10:13:24 GMT -8 @Guest 101 said:

As for speed - well they do claim things like 18knts...still can't see it myself...but then your the expert

Don't need to be an expert to be able to read specs and statistics, or to do simple mileage/time calculations. Sorry you can't see it.

[Northern Exploration]

Yeah lets build ice class vessels even though there is no ice in the Georgia Strait. All that extra weight will help Alberta establish another Heritage Fund of billions of dollars from the extra fuel burned, the Feds will finally have a balanced budget from the extra tax money generated and Canada will be debt free, and the fares on BCFerries will be sky high giving the rich the exclusive domain of all the Islands finally. Sounds like a win win overall to me.

[hergfest]

Ice Class is listed in the NorEx's construction spec on Flensburger's website.

[Scott]

Actually, we're going to do such a good job in the next 10 years of preventing global warming that, in conjunction with some major volcano eruptions, we will experience global cooling to the extent we will need ice class hulls on the coast. Don't you see? BC Ferries takes every percaution. I mean, who cares about fuel prices? Just jack up the fuel surcharge a few more cents ;D

[Ferryman]

Are we sure we have the right idea here?

I'm wondering if "Ice Class" is another way of determining the thickness of the steel on the hull, as a general rating.

I'm probably wrong, but just thought I'd mention what came to my mind as I was reading the previous posts.

[kerryssi]

I am reminded of the time the mate and I were standing on the deck of the Saltspring Queen in dock at SWB after our first morning crossing from Fulford. The mate asked "Doesn't it seem like we are standing closer to the water" I confirmed that. We got the manhole in the deck plates opened and found 12 feet of water in the forward hold. It seems that the evening crew had hit a log and didn't report it as they saw no damage. The packing around the shaft had been knocked loose and a slow leak had developed. No damage to the hull.

[Guest 101]

Chris,

You are partly right. Ice glass is generally the thickness of the plate and spread - spacing of the frames - which gives the hull it's overall strength. If you add in a shorter space on the frames - hence you need more frames - increase weight. Add in the additional thickness of the plate and that also adds in weight to the hull structure.

We also have to add in the cross box girders - to handle the additional strength of the frames - or scantlings.

In todays ship building - like in aircraft and vehicle manufacturing - there are trying to make the product a lot lighter. In ship building they reduce the size - thickness of the plate but add in more frames - which still give the hull it's strength.

We want the hull - vessel to be as light as possible - as water is a very sticky substance in which to push an object through. You also want to keep as much of the surface of the hull out of the water as possible. So very large flat hulls are not that efficient, and you need more power to push them through the water, where as a sharp V shape hull, has a lot less "material" in the water - hence - less "sticky" substance to pull it back - and therefore you need less power to push it through the water.

[Deleted]

So it the thickness of the hull and the framing width.
And they have them on more freighters that tackle the arctic i heard from a bcferries captain that when it starts to get too icy for the freighter's to go through it forwards they turn it around and theres a big circle in the ice from where it turned around and believe it or not they use they 'r re enforced propellers to cut through it pretty cool if you ask me.

[Deleted]

i thought it would be interesting to make a poll and see what happens

[cohocatcher]

Re: the poll - the hull - no - the drive functions (because of log strikes) yes.

[oceaneer77]

Hi All

Ice Class is a misleading term.. as their are many different classes of ice class.
The differing classes will determine the operating limits of the vessel. Some vessels are only slush boats that have moderately reinforced bows. Other vessels are full icebreakers with proper ice breaking hull designs and machinery systems that can operate in heavy ice conditions.

So just saying that a vessel is ice classed says very little.
You must also remember that ice classed and icebreaker are not the same thing.
You cannot have a non ice classed icebreaker but not all ice classed ships (only a small proportion) are icebreakers.

To build to ice class into our ferries?? just plain silly unless we plan on selling them to the east coast.


oceaneer77

[Nick]

From what I understand, ice class is a generic term meant on general reinforcing of the underwater sections of the ship. It can mean the hull, and/or the propulsion system.

A ship is not "ice classed" or "not ice classed". It isn't that cut-and-dry, as there are varying levels, not only in general, but also for the different components of the ship.

here are the TC "ice class" classifications. It is a very long and technical page, but it outlines the different classifications.

For our waters, I believe that some reinforcing is necessary to the PROPULSION SYSTEM to protect against log hits. I don't think that the hulls need any special protection, as they are built to withstand other forces, that are a lot greater than a bump from a log.

I think BCF and Flensburger use the term "ice class" because it is something everybody in the shipping industry can relate to. As Markus said, there isn't a such thing as a log class, because those hazards aren't present in many areas of the world.

[D'Elete BC in NJ]

hahaha...to start a tradition with oceaneer77 ;D, I will propose a new appended name for "ice class"..."hull strength rating indicating anticipated conditions in operating environment" or "HSRIACIOE" for short. This acronym can be pronounced simply by sneezing...a feat easily accomplished given the usual operating region for ships falling in this category.

[oceaneer77]

Hi All

Nick,,Ice classed.. Lloyd's will give a ship a special classification. Lloyd's of London has 5 classes (from memory) all in varying intensity. Most other classification societies have a Similar arrangement.
Sorry but i don't follow the TC stuff as we are off on our own....so i cannot comment.

HaHA BC nJ we should start our own class society and baffle them all with new acronyms