Re: PRESSURE HULLS

[VBra676539@aol.com]

In a message dated 5/5/99 7:39:39 PM, ray.keefer@eng.Sun.COM writes:

<<Hi Tom,

Sorry I didn't get back to your last mail. Here are some comments.

> 	Just in case you were really serious, I must tell you that I doubt 
> you could do any better than contacting George Kitteredge 
> (Kittredg@midcoast.com) for a set of plans to one of his submarines. All 
the 
...
> thinner material wall thickness in LP tanks--it looks like a sub hull, and 

Don't talk to George about LP tanks. He thinks they are a death trap waiting
to happen. Mostly because you don't know the theoritical strength of the
metal. By the time you send a sample of the tank metal out to get it tested
you can fabricate what you want from scratch. The hull actually costs in the
high hundreds of dollars.

Kittredge's designs are basic and simple. Talk to George. Get his video.
You will get an idea of what he is offering.

Also there is a company, Lake Diver (?... see web site under Sources ->
Kittredge), that sells his designs already manufactured. IF you got
$250,000 and don't want to make it your self. Comes certified though, 
almost worth it.


> 	As an illustration of just how tough these little boats are, check 
> this out. One of George's K-350s was chained down on deck of a ship that
> sank  in the Sea of Japan in a typhoon.  The ship was 100' long and was
> salvaged  after a couple of months from 900' of water.  The sub was intact. 
> No  leakage, no failed seals, and no visible hull distortions!  The thing 
is 
> built like an anvil! Hope this helps your ruminations some.
> Regards,
> Vance 

My understanding is that Kittredge derates his designs by 50%. So the 
K-600 is meant to operate at 600' max but the calculated crush depth
is 1200'. I am not sure if the K-350 is calculated to crush at 600' or not.
Surviving at 900' for months is a great testimony of his designs.

Regards,
Ray
>>

Tom and Ray,
	I agree with George in that materials control and quality control are 
essential elements.  If you don't know what you started with, then you'll be 
hard pressed to figure out what you ended up with.  And George probably based 
his original stuff on the US Navy requirements which require test depth to be 
2.25 times calculated max operating depth.  ABS and Lloyds require 1.5 times.
	One option I have not pursued is the possibility of a tank 
manufacturer building me a hull from my own material.  I'm not sure I would 
mess with it these days, but it seems like a possibility if you have a 
fabricator in your area.  They definitely have the expertise to roll material 
to specific roundness and weld and NDT them.  Anyone tried to go that route?
	I know the Lake Diver people. The LD itself is a K350 stretch and 
nicely done indeed.  The boat has done a bunch of dives, was tested to 500 
feet per George K's expectations, and has done plenty of interesting things 
since it went in the water ten years or so ago. Web (Maynard) told me that 
his sons had built a second hull but that was several years ago and I don't 
know what ever happened to it.  I tried their email but had no response.  
Anyone else had any luck?
Vance