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Lead for Nuclear Plant / Industry
The main role of Lead Metal in Nuclear Industry is to avoid the
radiation to escape out of the reactor. It basically acts as a shield
for the harmful radiations that are produced at the time of nuclear
Process.
The complete segment consists of 12 circular discs of Lead Metal which
are of different shapes. The complete unit is about 70cm in height and
500kg by weight. This segment is an integrated part of a large machine
setup that is used in Leakage detection of Heavy Water in a nuclear
reactor. The segment we have made is used in a chamber surrounding the
Heavy water storage in a Nuclear Reactor.
As we all know that Heavy water is an important type of coolant in a
Reactor whose job is to slow down the fast moving Nuclear Fission
reaction. It de-accelerates the speedy neutrons and halts the system
when needed.
In a fission reaction, besides the two fission products, a few (in the
case of U-235 2.47 on the average) neutrons are emitted. The principle
of chain reaction is very easy therefore: a U235 nucleus is hit by a
neutron, upon which fission occurs at a high probability.
 The
neutrons produced in this process can cause more fission; moreover,
200MeV energy is released each time. Consequently, the process becomes
self-sustaining and no external neutron source is needed any longer. If
the neutrons produced from fission induce only one new fission (because
of escaping from the system or being captured inside), we say that the
chain reaction is of constant intensity. If the neutrons generated from
a fission reaction induce more than one fission than more and more
fission reactions will take place in a unit time and the chain reaction
will be diverging.
In order to stop this reaction Heavy water moderator is used which is
highly contaminated and toxic for all living organisms and thus it
requires proper handling & precautions.
Lead Metal is used for its leakage detection which avoids its radiation
to move out. This is mainly because of its properties that make it to
play an important role in Nuclear World.
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