b. Tanks Carrying Oils. This type of tank is best
are necessary to permit the release of gases and
pressure less than that required to lift the safety valve.
cleaned with steam. A jet of stem will be blown into the
Dome covers without these holes should never be
tank, the steam vapor will condense on the tank wall
applied. It is necessary to inspect to see that the dome
and run down to the bottom of the tank, taking the oil
cover chain is secured to the tank so that the cover
with it. Before applying the steam, it is necessary to
cannot slip off and fall.
remove the outlet cap and to open the tank valve,
thereby allowing the condensate and oil to run out. After
h. Tank Car Tanks. After any repairs requiring
4 to 5 hours of steaming, a carman should enter the
tank and sweep out the residue The final step is a
welding, riveting, calking of rivets, or hot or cold forming
thorough flushing with cold water.
to restore tank contour of tank cars used in Interchange
service in CONUS, the tanks must be retested as
prescribed by paragraph 173.31, DOT Regulations (49
c. Tanks Carrying Acids, Fats, Heavy Greases.
CFR Part 173) before return to service. Glass, lead, or
Tanks that have transported these commodities must be
rubberlined tanks must be retested before the lining is
cleaned by boiling out. This is accomplished by filling
renewed. Interior heater systems must be retested
them with water and adding four or five hundred pounds
before return of the car to service after repairs to, or
of caustic soda. A steam hose should then be inserted
renewals of any part of the system.
into the tank and turned on. Tanks of this type should
be boiled for 48 hours before the solution is drained out.
9-35. Tank Cleaning
After this treatment, the tank must be thoroughly
washed out with cold water before it is safe for a
workman to enter. As this caustic solution will cause
a. General. When it is necessary to repair a tank,
painful burns if it comes in contact with the skin, rubber
It must be thoroughly cleaned so as to be safe to enter.
boots, gloves, and oil-skin clothing should be worn when
Often the fumes remaining after the load has been
the solution is handled.
discharged are highly flammable or toxic.
procedures following are prescribed for different
Section VIII. FLATCARS
cylinders and foundation brake gears of the
conventional type of flatcar cannot be used in
depressed-center flatcars; hence, brake cylinders with a
The Department of Army 40-ton flatcar is specially
separate foundation gear for each truck are required.
designed for foreign service as the basic component of
Cylinders may be truck mounted or body mounted. Rail
the knocked-down fleet The other components (except
movement of ordnance and engineer material and other
tank cars) are simply flatcars with their respective types
equipment with vertical dimensions exceeding those
of superstructure (high- and low-side gondolas and
permissible for mounting on regular 40or 80-ton flatcars
These components are shipped
is sometimes possible on depressed-center flatcars;
packaged and are easily assembled as outlined in TM
however, the load limit of the depressed-center flatcar
552220-201-35. For the movement of ordnance and
will not equal that of the regular 80-ton flatcar. The
engineer materials, or other equipment weighing over 40
usefulness of the depressed-center car is measured
tons, a standardized Army 80-ton flatcar has been
primarily by the added headroom it affords.
designed to meet most theater operating conditions. No
conversion of this car is anticipated. It is mounted on
9-38. Maintenance and Repair
six-wheel (3-axle) trucks to avoid exceeding the low axle
load limit on track and bridge structures of foreign
railways. The 80-ton flatcar, like the 40-ton flatcar, is
a. General. The life expectancy of flatcars- is
shipped knocked down and packed so that it can be
materially affected by the adequacy and quality of the
assembled in the field with minimum effort.
maintenance and repairs performed. This is because of
the tremendous load transported on flatcars. The
9-37. Depressed-Center Flatcars
structural material used in flatcar construction consists
of members rolled, shaped, extended, or cast. These
various members are combined and fabricated to form a
A minimum design capacity load of the depressed-
center flatcars (fig 2-5(2)) In service on the railroads of
the United States is 70 tons. Body-mounted airbrake