Re: Tank cars

"Howard Garner" <cascaderail@[EMAIL PROTECTED]
> wrote in message
news:igh8k.11993$3F5.6929@[EMAIL PROTECTED]
 bladeslinger@[EMAIL PROTECTED]
 wrote:
: > On Thu, 19 Jun 2008 23:06:18 +1000, "Bill Whale"
: > <wwhale@[EMAIL PROTECTED]
> wrote:
: >
: >> And the next question is, why do modern tank cars have no domes?
: >>
: >
: > They do have domes, they're just not as big as on the older cars.
All
: > the dome was was a cover for the valves.  But a lot of cars now
do
: > have a small cover over the valves.  Depends on the car
:
: Not right!
: The dome was for the expansion of the product. It may also have
covered
: various valves, etc.
: Today the control the loading to provide for the expansion,
yesterday
: the filled the shell of the tank andthe dome took care of the
expansion.
:
: Howard Garner

I loaded tank cars at Pfizer Chemicals some years back. All I ever
saw under the domes was pipes and pressure gauges. We had strict
rules about how much material could be loaded into a car specifically
to prevent expansion spills or tank/pipe ruptures.

I never got a good explanation why, but several materials were
actually loaded through the 'discharge' valve on the bottom of the
car. The air in the car vented out through a pipe on the top as it
filled. It was your job if you overfilled and blew material out the
top.

Len