Safe Handling of Tank Containers - ITCO

ICHCA International Safety Panel Briefing Pamphlet No 30
5.5.6 Non-mandatory Fittings on T50 Tanks
5.5.6.1 Some T50 tank containers may be fitted with devices for measuring filling
levels. Often these will be fitted in a recess similar to that described in
section 5.3.6 in the rear end of the shell.
5.5.7 Tank fittings must only be operated by a suitably qualified technician
or operator who has in their possession the full details of:
the load status of the tank
the cargo
whether the tank is under pressure or not
5.6 Fittings on T75 Deeply Refrigerated Liquefied Gas Tanks
5.6.1 Liquid and Vapour Load / Discharge Assemblies
5.6.1.1 The loading and discharging assemblies on tanks intended for the transport
of T75 deeply refrigerated liquefied gases are, by far, the most complex.
Any number of valves and pieces of pipework that are usually found along
one side of these tank containers may be found within one or more
compartments. For each compartment there will be a connection for the
liquefied gas to enter or leave the tank as well as for the vapour. These will
have three closures as with the tanks for liquids and pressure liquefied
gases. However they will be very different to the three closures on the
other kinds of tank. This is due to the nature of the substances carried and
the design of the tanks which, as noted above in paragraph 4.4.2, usually
have a steel outer vacuum jacket surrounding the actual shell. In place of
the foot valve fitted to liquid tanks, there are usually two external valves. The
inner valve is usually pneumatically operated. It requires a source of
pressure to be attached to it to open and hold it open.
5.6.2 Controls for Filling Levels
5.6.2.1 Additional valves may be fitted to control filling levels. It is commonplace for
these tanks to be fitted with internal vertical pipes rising from the floor nearly
to the top. Each one will be marked with the name of the gas for which it
gives the maximum filling level. Once the shell has been filled to the
required mass, for example so as not to exceed the maximum permitted
weight of its CSC approval, liquefied gas overflows. There will be valves and
associated pipework to control this process
5.6.2.2 These tanks are also usually fitted with flow gauges, usually circular, by
which the filling level may be determined.
5.6.3 Pressure Raising Coils
5.6.3.1 Some of these tank containers can self-discharge. This is achieved by
diverting some of the liquefied gas into a pressure raising coil to turn it into
gas and thereby raising pressure. This source of pressure is piped to the
top of the shell to push out the remaining liquefied gas. Tanks containers
with this possibility usually have a visible pressure coil, perhaps underneath
or on the opposite side to the valve compartments.
5.6.4 Cryogenic Pumps
5.6.4.1 Some of these tank containers will be fitted with their own pumps located in
the compartments on the side. These pumps have to be cooled down to
the temperature of the liquefied gas inside the shell before they can be
used. There will be associated pipework and valves on such tanks for the
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