Just recently, I read somewhere
that villagers in Haryana bought massive amounts of gold from a
particular man just before the great Recession in 2008. Apparently, the con man
said he had massive debts to pay off for his factories and was selling the
gold at half the price. The public bought the yellow metal. It was Gold..but
just about 20% of it and the rest 80% was copper.
Now.. Isn’t that a GROSS? Buying
yellow metal instead of gold, just because the colours are the same. About 45
people were done in!
Unfortunately, such things happen
regularly in the industry. Unless one buys from a BIS certified shop or
material, one can't be sure. It’s also rumoured that many jewellery stores
are still selling higher percentages of copper in gold. The issue said to
be rampant in other forms of valuables like diamonds and platinum as well.
This phenomenon is not restricted
to India alone, but most parts of the world where Standardisation of the Value
is not performed.
Industrial Products and
consumables are also affected where purchases are based on a single page
‘literature’.
I am narrating an experience,
similar to which many of you may have already experienced.
We have a Electronic Security
Division and had quoted in a tender at AAI for installation of CCTV cameras at
the airport. The specs called for 1200 tvl (TV Lines) and Day night
Functionality of certain High Performance Cameras.
When bids were opened, we found
some suppliers to have quoted at 40% lower than the estimated cost. The
catalogue was the only proof of backing the claim. Any clarification required
by the Airport from the supplier.. was made on a letterhead.
We had a situation where nobody
could verify the claim that the cameras indeed had 1200tvl. However
due diligence and other factors were employed in subsequent tenders.
Care to be taken in Purchase of
Ultrasonic Cleaners
Engineering Goods generally don’t
have such issues, due to the availability of test houses and BIS, JIS, ASTM and
other norms that have been made.
However, these will be difficult
to prove in the Ultrasonic Cleaning Business. By making some hypothetical
comparisons, I hope to draw your attention to some adversely affecting
scenarios:
a) How
can one be assured of a correct power rating of the Ultrasonic? Have we bought
a 500 watt Ultrasonic or is it a re-labelled 300 Watt?
b)
Is the design good enough to ensure the entire tank gets the ultrasonic waves?
Or is it active in some areas only?
c) Is the
ultrasonic transducer working with 30,40, 50 or 90% efficiency? Imagine paying
a market price of Rs.50,000/- for 250 Watt Single tank Cleaner. If a good
Ultrasonic Cleaner works with 90% efficiency and the one we have purchased is
working at 30% efficiency…its same as paying Rs.1, 50,000!
d)
Is there a guarantee on the life of the Ultrasonic? Can someone support it
after warranty? When the Ultrasonic transducer fails, it is almost always
necessary to change the tank too. Low cost Chinese models will find it hard
placed to do so. By the way... I offer lifetime warranty on all transducers on
our equipment!
Why Transducers are
Important
Transducers are of mainly of
three types : Piezoelectric and Magnetostrictive and Pull Push.
Piezoelectric is made of a piezo
ceramic disc sandwiched between two strips of tin. When power is applied to the
tin bits, it creates a displacement which is what creates the vibration. When
the frequency of vibrations are high, it creates the cavitation in the tank
through the stainless steel enclosure.
Magnetostrictive transducers are
similar except that it has lead rings that can be activated for shrinkage by
getting magnetized. The advantage is that the rings do not get magnetized over
an extended period of time.
Pull Push transducers are fitted
inside the tanks. They are rod like and have an insert sleeve with the
cavitation being created on both ends of the rods. These transducers can
produce about 98% efficiency.
To be really effective, three
aspects have to be taken care of:
1) Bonding
2) Efficiency
3) Inertial Mass
Inertial mass is something like
the pressure needed to create movement.. If you need to move a train, you need
engine with power and momentum that is greater than the train.. Right? Can’t
move it with a matchstick. It doesn’t matter if the matchstick is held by a
railway engine. It just won’t move.
The same way a loaded Ultrasonic
tank (water plus material), will need a series of transducers, which are more
heavier than the tank plus the liquid weight put together.
The book has an elaborate and
simple explanation about transducers, That will also explain in detail, why
efficiency and bonding are better with Magnetostrictive transducers.
Though there are other components to
an Ultrasonic Cleaner, the heart is the transducer and its up to us to
take a call on what is the long term cost we can pay , for Cleaning!
