The Iranshahr power plant
explosion is pretty much all over the news bulletins and discussion forums, but
it seems that nobody knows the exact cause of the explosion. So let's try to
take a better look at what really happened, where things went wrong, and what
may have caused this disaster.
There are several hazards
involved while working in a power plant, with the most dangerous one being
severe explosions that claim hundreds of lives. Recently the steam turbine
generator explosion at the power plant in Iranshahr (a city in Sistan and
Baluchistan province of Iran) has been the most horrific powerplant disaster,
so let's look at the Iranshahr power plant explosion in particular.
From a logical point of view,
there can be several reasons for a powerplant explosion. For example, the
generator end turns in the stator could have shorted/exploded massively or
hydraulic/lube oil could have leaked and sprayed, spreading the fire. The most
common possible cause that has been reported for the turbine steam generator
explosion is coupling failure. Let us go through this particular cause for
explosion in detail.
Normally, couplings are very
important parts in any kind of power transmission system to facilitate transfer
of power from one part to another. If indeed coupling failure was implicated,
proper maintenance of the couplings used in the power plant may have prevented
the accident. Regular inspection of couplings is very important for the
reliable operation of the power plant as well as to prevent any untoward
incidents.
These couplings have to be
checked regularly for indications of wear and tear; they also have to be
cleaned and lubricated on a regular basis- especially in demanding operating
conditions and adverse environments.
Generally, there are two types
of couplings:
○ Rigid couplings: These couplings are
normally used in applications where there are two co-axial shafts. They can be
further classified as muff couplings and flange couplings.
○ Flexible couplings: Such couplings are
used when there is no assurance of co-axiality between the two shafts to be
connected. They have an elastic component between the connecting units. They
are also commonly used in applications where there are possibilities of shocks
during transmission.
Apart from this general
classification, couplings can also be classified based on the area of its
application. Normally, gear couplings are used in power plants.
Huge electric motors are used
as feed pumps for an oil-burning powerplant. The feed pumps and other
components have to be bonded mechanically. This is where the coupling comes
into picture; though it is a small part of the power plant, it plays a vital
role in the operation. The failure of the coupling can bring the operation of
the power turbine to a stand-still.
However, the noteworthy fact
is that the Iranshahr power plant had three oil burners in the same room, which
is three times what you actually see in case of most of the other power-plants.
No wonder, the coupling problems led to such a disaster.
Another noteworthy aspect of
this incident was that the power turbine was found missing after the blast, and
various reporters have different stands on this. Since, we don't have any solid
evidences behind the disappearance, we're not going into the nitty gritty of
this specific matter.
If the coupling fails even
with proper maintenance, then the cause for the explosion could be related to-
○ Improper installation of coupling
○ Poor selection of the coupling
○ Operation beyond its design capabilities
There are many more things
that could have gone wrong, but the general notion is that coupling failure was
the root cause. Once again it's worth mentioning that no specifics of the
actual incident are really available, and these are just speculations!
Having seen this very tragic
incident, it's high time that everyone stood up on their toes, and looked at
things more seriously. There are flaws at almost all the power plants, and the
only way out to prevent accidents like the Iranshahr power plant explosion is
to know the external signs that indicate coupling failure and correct them.
Some of these indications are
excessive wobbling or noise, abnormal noise, or lubricant leakages. However,
there's much more to it than just pointing out possible causes behind the
explosion. The most important thing is that everyone must learn from this
mishap, and make every possible effort to ensure that something similar never
happens again in future.
The most obvious advice that
would come to your mind at this point of time is that the couplings used in the
power plants must be inspected regularly for the consistent functioning of the
units and to prevent any unexpected mishaps. But, remember, it may not be the
same mistake every time. It could be something else rather than just coupling
failure next time around. But, we can just hope that such a dreadful incident
never takes place again.