Surface World January 2020 Surface World January 2020 | Page 30

PRETREATMENT, SURFACE PREPARATION, DEGREASING & CLEANING
Technology meets chemistry –
Why having the right balance
is critical for component cleaning
When it comes to the
cleaning of engineered
components it’s often
considered that the physical
washing machine is the
only important part of the
process. Cleaning additives
and detergents are merely a
supporting element. “It’s not just about knowing what
contaminants have to be removed. The
combination of an intense washing system
with an inappropriate mix of chemicals and
detergents could damage the substrate and
lead to the cleaned component’s failure.”
For MecWash, one of the leading innovators
and manufacturers of aqueous parts cleaning
systems, the approach has to be about three
crucial elements: the technology, the chemistry
and the product that is being cleaned. MecWash works with a customer to
understand the type of components being
cleaned and what results are required.
Analysis and trials then allows the correct
wash process and chemistry to be defined.
“It’s quite easy for a company to go out and
acquire a washing system without understanding
the importance not only of the chemicals
required, but the impact they can have on the
substrate of the component being cleaned,” said
John Pattison, managing director of MecWash
based in Tewkesbury, Gloucestershire.
MecWash has invested heavily in its own
laboratory at its headquarters to develop,
design and formulating chemicals for common
and bespoke component cleaning applications.
So how does the
process work?
The process begins with an audit of the
customer’s cleaning requirements. This is
thorough and covers key areas including:
The substrate of the components being cleaned
Are the components metallic, non-metallic
or hybrid?
What is the type of contamination?
Do the components need to be brightened
as well as cleaned?
Are the components as cast, machined,
polished or a combination?
The geometry of the components and
critical features
What is the cleanliness specification?
What is the process directly before the
wash process?
What is the process directly after the
wash process?
Does the component need to have any
long-term corrosion protection after
the wash process?
What is the size and weight of the
components?
Physical analysis is also undertaken.
This includes:
Chemical compatibility with substrate
Removal of contamination from the
component’s surface
Removal of the contamination from the
process solutions
Millipore testing
Gravimetric analysis
Surface energy tests (eg water break)
Visual inspection or bespoke tests.
“The process is intense and
thorough. It has to be to ensure the
complete system and process will
remove the contaminants to the
highest levels possible without
damaging the components during or
after the washing process,” said Mr
Pattison.
“It could take days or months,
depending on the type of product or
process and the end results required
by our client and their customers.
Manufacturers in the aerospace,
automotive, fluid power and medical
sectors are ever more demanding.”
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JANUARY 2020
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