When speaking of "corrosive
chemicals" the general context is in the acid filling and bleach industries.
Hydrochloric acid and sulfuric acid are common applications. Bleach means
not only low laundry concentrations but also industrial concentrations of sodium
hypo-chlorate. As discussed in other sections, the Time Gravity Filling
Machine is used for filling free flowing, non foaming liquids and it has some
degree of flexibility of container size and geometry even though corrosives
filling is typically dedicated to a particular product with a very limited fill
chemicals are so corrosive to machinery that even the atmosphere where the
filling machines are installed can be destructive to any metal assets in the
area as well as hazardous to personnel. Metal fasteners used in the assembly of
a conventional time gravity filling machine will degrade within 6 months and the
filling machine will start to come apart. Even the control system is isolated so
that it is continually being purged with clean outside air even when the machine
is not in use. This protects the electronic components from premature failure.
Time gravity filling machines
for corrosive products are constructed entirely out of inert plastic and
fiberglass with even the fasteners (nuts and bolts) being made of fiberglass.
All valves and fluid paths are specified for compatibility with the extreme
products being filled. There is always fully enclosed guarding to protect
personnel form splashing and spray during operation. These construction
techniques and materials are somewhat unique and therefore these machines are
typically manufactured at a premium to those made from mild or stainless steel.