Finishing - September-October 2020

42 GALVANIZING
Speeding up the process
SIEBEC principally offers three tried and
tested technologies for the Galvanizing
industry:
• Oil removal from the degreasing baths
• PUSH-PULL agitation of the Acid pickling
bath
• Iron removal from the Flux bath.
The customer has a 60 m³ volume Flux
tank, running at 50 - 60°C. Unfortunately they
experience processing quality issues related to
the variation in iron concentration within the
flux process.
Hot-dip galvanizing pre-treatment requires
the maintenance of two critical parameters.
One being the oxidisation of iron (Fe² to Fe³ )
and the second, iron concentration within the
flux solution that should be maintained below
1 g/l.
The SIEBEC solution was to supply and fit 3
P51-A30 filters, each fitted with 4 L-TECH
50µm pleated cartridges, allowing iron
particles to be extracted from the 60 m³ flux
tank.
Thanks to the SIEBEC designed installation,
our customer now maintains the iron
concentration in the flux process below the
desired 1 g/l and no longer experiences the
quality problems they had been experiencing
prior to the P51-A30 filters being installed.
The solution has proven to be cost effective
as the filter media is very quick and easy to
clean, minimising waste. The L-TECH re-usable
cartridges only need to be replaced every 4 -6
months.
PUSH-PULL agitation
Pumped agitation of HCL Pickle tank.
SIEBEC developed and designed this
technique specifically to create a uniform,
evenly distributed laminar flow of the pickle
acid across the entire surface of the parts
anywhere within the tank. This system has the
additional benefit of increasing the
effectiveness of the pickling solution during
the colder months. When cold, longer pickling
immersion times are required to attain the
same reaction. Alternative technologies are the
addition of air agitation or solution heating but
both of these have an adverse impact on the
environment and the fabric of the building.
Fitting a conventional Eductors system to
achieve the same results is problematic as
anything at the base of a large acid pickle
tank is at high risk of being caught by the
work and dragged out of the tank.
Additionally, PUSH-PULL system demand
significantly smaller pumps and have proven
to be an efficient and a robust solution for
pickling applications.
Benefits of the system
• Faster pickling, especially during low
temperatures when the acid becomes almost
inert.
• Increased productivity, greater throughput
• Improved homogeneous mix of the acid,
within the tank.
• Minimise air entrapment, improving
quality.
Oil removal of floating oils using a coalescer
to skim off the surface of the degreasing tank.
The benefits of removing the oil are that the
degreasing solution will usually last longer and
the oil is not dragged by the work down the
line into other process tanks.
SIEBEC has a comprehensive range of
proven products available for filtering,
pumping, eductor agitation, dosing, filter
media, precious metal recovery, ion exchange,
organics removal, effluent treatment and
vacuuming of process chemistry and waste
water. Many products are stocked and
typically available for next day delivery from
our Stafford factory.
Finishing - September/October2020