On 2010-10-26, at 2:42 PM, Clark and Eileen wrote:

I have a friend struggling with his tank car fleet (asked some questions on his behalf at N'ville) He asked me last night what TPI and TVI AAR codes mean. We guessed that TPI was a pressurized, insulated tank car, but haven't a clue about TVI.

TVI is an oddball designation, turning up only in the mid- to late-1960s (1966-1968 for sure). The definition is:

Tank car equipped with insulated container having an inner and outer shell with a vacuum in the annular space to AAR Specification 204-W.

Sounds like a giant thermos bottle to me!

Ian Cranstone
Osgoode, Ontario, Canada
lamontc@...
http://freightcars.nakina.net
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