When hearing the term “searching,” one doesn’t often think of liquids. But
when it comes to chemical process applications, you don’t want to underestimate
the importance of this attribute. When fluids are searching, they are looking
for a place to go. Any place. Normally, this should be through the discharge
ports. But if there are any weaknesses in the seals, diaphragms or other components
on your pumping equipment, searching liquid can leak and foul an operation.
Containment of
Coatings
To use a simple definition, coatings are a covering that is applied to the
surface of an object to improve its surface properties, such as appearance,
adhesion, wettability, and corrosion- and scratch-resistance. While easily
defined, the manufacturing process used to create coatings is very much a
complicated operation. It involves the blending of a variety of liquids –
including polymer emulsions and resin solutions – to create water-based and
UV-cured products. These liquids can be extremely viscous and hard to seal.
According to Martin Skillen, the best way to describe the liquids used in
the manufacture of coatings is “very searching,” especially when it comes to
the impact they have on production equipment. You see, as the General Manager
and Director of Hi-Tech Coatings International Limited, Skillen knows a thing
or two about what it takes to produce high-performance coatings. For 20 years, Aylesbury,
United Kingdom-based Hi-Tech Coatings has been a forerunner in the development
and manufacture of water-based and UV-curable coatings used by the printing and
converting industries. In those two decades, the company has transformed itself
into one of the world leading providers of clear coatings for a broad range of graphic
applications.
“At Hi-Tech Coatings, our guiding principles include quality, customer
service, short delivery times and innovation,” said Skillen. “By relying on our
experience and knowledge of polymer formulation and coating machinery, we have
been able to provide a rapid response to market needs and develop novel
coatings both for sale and for contract to other trade suppliers.”
By following these guiding principles and manufacturing high-quality
products by following an exacting production process, Hi-Tech Coatings has been
able to flourish within the graphic arts industry. In fact, business has been
going so well that in early 2013 the company moved into a new, state-of-the art
production facility in Aylesbury.
Finding the
Correct Pump
When transitioning to the new location, it was essential that Hi-Tech
Coatings installed the same, proven production technology that was used at its
previous facility and which helped contribute to its quality manufacturing
processes. This included the pumping equipment that the company relied on for
transferring raw ingredients from intake, through processing and on to finished
product filling and packaging.
As mentioned, the liquids used to produce coatings can be “very searching”
when it comes to their impact on production equipment. This is especially true
when it comes to the pumping equipment tasked with handling these difficult
liquids. For this reason, it is extremely important to identify the proper
pumping technology for the various components used in the manufacturing of coatings.
Not only do the ingredients of high-performance coatings have their own
unique handling characteristics, but they also require the need to be
transferred at various points within the production cycle, including out of
storage tanks or into mixers. This requires pumping technology that is
versatile enough to handle the transfer of these liquids, oftentimes in
high-pressure pumping applications. Additionally, given the wide range of
dynamic head pressures that are created due to the variety of viscosities handled
and the number of discharge points within the production process, positive
displacement air-operated double-diaphragm (AODD) pumps can often represent the
best technology to meet these requirements.
While utilizing AODD pumps for a variety of applications, the brand of AODD
pumps that Hi-Tech Coatings employed for several years at its previous facility
suffered from a variety of problems, including leakage through the seals and
clamp bands. In addition, the pumps were also experiencing problems with diaphragm
lifetimes.
“The pumps we were using for many years at our old facility were just like
consumables,” said Skillen. “Since the materials we use are ‘very searching’ we
would often find them leaking from the pump bodies. The diaphragm lifetimes of
these pumps were also very limited. We were constantly replacing broken pumps or
paying a considerable amount of money on repairs. This was bad for our bottom
line and something we had to move away from. We started to question the overall
value we were getting for our purchase. That’s when I tasked one of our employees
to begin searching for a better pumping solution.”
In 2010, Hi-Tech Coatings instigated an engineering research project to
examine alternative models of AODD pumps. It was this research that brought
Hi-Tech Coatings to AxFlow Limited, Ealing, London, UK, which is a longtime
supplier of Wilden® pumping technology. Wilden is a leading brand of
AODD pumps from PSG®, a Dover company, based in Oakbrook Terrace,
IL, USA. AxFlow is one of Europe’s largest suppliers of pumps and pumping
equipment with offices and service locations in 26 European countries.
“When Hi-Tech Coatings first approached me voicing their concerns with the
pumping equipment they were currently using, I knew right away that I had the solution,”
said Gordon Dewar, External Sales Engineer at AxFlow. “Since Hi-Tech Coatings
does not have a maintenance team on-site, I knew the pumps had to be simple and
reliable while offering a long meantime between failures. Another consideration
was that the pump diaphragms had to be compatible with a number of different
chemicals and applications. With all this in mind, I recommended installing
Wilden pumps.”
The Wilden
Advantage
Rather than remove all of the existing troublesome pumps in one go, Hi-Tech
Coatings started with a 1.5-inch Wilden Advanced™ Series Metal AODD
Pump with a bolted design for its distribution lines. Quickly proving that it
was the correct pump for the job, other Wilden Advanced Series pumps were
installed on the packing and filling lines, along with the
chemical-distribution system.
“For what we do, we need pumps that are reliable, require little
maintenance and really have no negative impact on our production whatsoever;
pumps that just go and run all the time,” explained Skillen. “When we switched
to Wilden, it alleviated the problems of leakage and diaphragm failures. Wilden
pumps also feature very simple maintenance.”
Wilden Advanced Series pumps are ideal for a variety of applications in the
paint and coatings industry because they feature a sealless, bolted
configuration that ensures total product containment, while the design of the
wetted path reduces internal friction, enabling the pump to deliver a
shear-sensitive operation that is mandatory when working with paint and
coatings. The AODD pump’s positive-displacement operating principle also
guarantees that the product flow will remain volumetrically consistent.
Other benefits of Wilden Advanced Series pumps include their ability to be
used in a wide range of pressure and flow specifications, self-priming and
low-wear operation, ability to handle difficult solutions, improved energy efficiency,
and overall low maintenance costs. In addition, these pumps can accommodate
deadheading during filling applications, a task that motor-driven pumps are not
able to handle effectively.
Wilden Advanced Series pumps are available with Wil-Flex™
EZ-Install Diaphragms, which are ideal for polymer and resin transfer. Wil-Flex
EZ-Install Diaphragms feature a flat-profile design that eliminates the need to
invert the diaphragm when rebuilding a pump, which allows for easy,
cost-effective installation and maintenance, along with increased flex life.
Conclusion
Having reaped the benefits of utilizing Wilden pumps for two years at the
former plant, the new facility was also equipped with brand new Wilden pumps.
“Before switching to Wilden pumps, the previous pumps were not giving
Hi-Tech Coatings the lifespan the company was expecting,” said Dewar. “After
two years of working in the old facility, the Wilden pumps were still
trouble-free and required nothing more than routine maintenance. So when
Hi-Tech Coatings was moving into its new facility, not installing Wilden pumps
wasn’t even an option for them.”
Since moving into its new production facility, Hi-Tech Coatings has
increased the production capacity of its water-based products upwards of 75%,
and with surplus space for more chemical-distribution lines, the speed of transferring
chemicals into mixing tanks increased and greatly improved the production
process. This was due in large part because the Wilden pumps installed at the
new facility are able to operate trouble-free while providing high levels of
accuracy and controllability of the volume of ingredients going into the mixing
operation.
“We found that the Wilden pump is very reliable and economic to run, which
is why we specified them for the new facility,” said Skillen. “The new plant
gives us a more automated approach and additional capacity for the future and
we see the Wilden pumps as being a reliable part of our manufacturing capability
moving forward. We were recently involved in a project in Detroit, MI, USA, and
we standardized on the Wilden pumps for this production plant as well. Wilden
pumps have been such a reliable pump for our business; I consider them the
Rolls-Royce of the pump world.”
For
more information on Wilden AODD pumps, please go to
www.wildenpump.com