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Cleaning Equipment Maintenance
By Ed Sunkin
The saying, "An ounce of prevention
is worth a pound of cure," definitely holds true when it
comes to the operation of cleaning equipment in rebuilding shops.
According to David Zehren, product manager,
stationary equipment for Georg Fischer Disa Goff, Inc., Seminole,
OK, routine maintenance of cleaning equipment impacts all rebuilders,
no matter how large or small. "The issue of lost production
and down time from neglected equipment is a subject that no rebuilder
can afford to overlook," Zehren said.
Steve Boomgarden, product advisor for The Hotsy
Corp., Englewood, CO, echoed this viewpoint, and said routine
and proper maintenance is important not only for cleaning equipment,
but for any piece of machinery in a shop. "Without proper
maintenance, the chances of breakdown increase dramatically,"
Boomgarden advised rebuilders. "When certain types of cleaning
equipment become inoperable due to the lack of, or poor, maintenance,
it can be devastating to your shop's daily operation. In many
cases, if your cleaning equipment is down, so is the rest of your
Besides improving the life of equipment, Bill
Wessel, president of Kansas Instruments, Council Grove, KS, said
the more efficient the maintenance, the more efficient the machine
will operate to save a shop money. "Costs are reduced directly
by the machine cleaning faster when it is maintained correctly,"
Wessel said. "Costs are reduced indirectly by lower expended
costs such as utility bills and replacement parts that will be
needed if maintenance is not performed."
Boomgarden said nearly all cleaning equipment
manufacturers will have a recommended maintenance schedule to
follow. "A typical routine maintenance schedule for most
cleaning equipment would include checking for cracked hoses, seized
pumps due to a lack of oil, sooty coils, screen cleaning, nozzle
changes, changing the oil and any filters, greasing requirements,
etc.," Boomgarden said. "This depends on the equipment
and the number of components it has."
Boomgarden said having a comprehensive maintenance
checklist by the cleaning equipment is a good idea. "Regardless
of who performs the maintenance, the checklist will ensure that
all pertinent items are looked at and maintained," he said.
When dealing with manufacturer's maintenance
requirements, there are some general, common-sense guidelines
to consider which will save the shop unnecessary aggravations.
First, keep each cleaning unit's instruction manual clean, orderly
and near the piece of equipment it belongs with. Second, ask your
employees to handle the manuals only with clean hands, and request
they do not tear out any pages. Third, make a photocopy of the
manual and keep it in a secured place in case the original does
get misplaced or destroyed. By taking good care of the manual,
you can help ensure that it will be available for any employee
who needs to refer to it for operation or for reordering parts.
The type of cleaning equipment will obviously
dictate the costs associated with its maintenance. For instance,
if you purchase a filtration mechanism, you will likely have to
service filter membranes, replace filter bags/membranes/liners,
and dispose of spent filters as a hazardous waste. This is also
the case for chemical flocculating accessories for which you may
have to purchase flocculating chemicals and filter liners, and
dispose of the increased volume of sludge and filter liners as
a hazardous waste.
One point to ponder before purchasing new cleaning
equipment is to look into buying from a local distributor because
the shortened distance may reduce shipping costs of parts and
allow prompt service of equipment during any break-downs.
When applicable, intake air filters should
be checked which minimize intake dust which can cause finish flaws.
Kansas Instrument's Wessel said ash should be removed weekly from
the oven floor. "Also, the burners should be checked and
blown off with clean, dry air monthly," he said. "Any
dust collected inside the burner reduces its efficiency."
Jet washers equipped with oil separation technologies
may require about 20 minutes of daily maintenance at the end of
the day while the machine cools. Those with filtration may require
filter membranes be cleaned once a week, also about a 20-minute
job. "Some filters never need replacing because they are
made of a screen mesh," explained Hotsy's Boomgarden. "These
filters need only be removed, washed off with a hose and replaced.
However, other types of filters such as polyspun fiber or cloth
fibers must be replaced."
Most machines, depending on the frequency of
use, require periodic sludge removal and cleaning. This is typically
undertaken between one and six times a year and can take up to
two hours at each cleaning. Some companies are marketing sludge
dryers or flocculating technologies. These processes may require
even more service.
Spray nozzles on these units should be inspected
regularly to avoid clogging. "Under normal conditions, spray
nozzles will not get clogged," Hotsy's Boomgarden said. "However,
occasionally a nozzle will clog due to either bad detergent that
leaves deposits, or an accumulation of dirt and debris. To clean
out the nozzle, simply remove it, tap it on a hard surface to
remove the debris, wash it out and replace."
Boomgarden said most nozzles only need to be
replaced when they wear out. Depending on how often the equipment
is used, this can range anywhere from one to five years. "Nozzles
are usually easy to find and most manufacturers use a standard
1/4ý or 1/8ý male-threaded nozzle," Boomgarden
said, and offered the following recommendations to prevent clogged
- Use only good detergent.
- Keep the equipment clean by removing sludge
from the solution tank.
- Be sure the filter is clean or replaced
on a regular basis.
Kansas Instruments' Wessel noted other causes
for plugged nozzles that rebuilders need to be aware of. "Removing
any stringy, non soluble substances such as silicone from the
part before it is cleaned will keep nozzle plugging to a minimum,"
Wessel said. "Sediment build-up in the bottom of the machine
causes most nozzle plugging, so tank maintenance is the key."
Goff's Zehren said his company's HydroPulse
equipment, which uses a water wheel to centrifugally throw hot
water in large droplets from large openings on the star-shaped
wheel, was developed to eliminate the need for spray nozzles and
their problems, yet still perform the same cleaning requirements.
"By eliminating nozzles, we have eliminated the single most
costly and timely wear item associated with pressure washing and
cleaning equipment," Zehren said.
Shot blast equipment
According to Gus Enegren, president of Viking
Corp., Wichita, KS, dust collection is an often overlooked and
important area of shot blast maintenance. "Most users tend
to focus on wear items, such as "how worn are my blades'
or "is my material handling system worn out,'" Enegren
said. "Too often they couldn't care less about the cleanliness
of the dust collector filter media or the shot work mix. But those
two issues, probably more than anything else, will determine the
success of a blast cleaning operation."
Blast machine manufacturers said their maintenance
checklists have dust collector condition as a "check daily"
procedure. "The shot blast equipment could not operate without
a dust collector removing the airborne dust and assisting the
lip separator to remove heavy particulate from the abrasive mix
(shot)," Goff's Zehren said, adding dust collectors for the
most part are self-maintaining. "They do however require
a timely and consistent removal of the waste dust. If waste dust
is not removed on a timely basis, it can overfill and be re-entrapped
onto cartridges or the filter," Zehren said.
And speaking of filters, Zehren said replacement
of these items in a shot blast machine is determined by the work
being performed and the load of dirt. "Under consistent and
proper operating conditions, filters normally last one to three
years," he said. "If, however, a bag or cartridge is
damaged, torn or broken, then that filter needs immediate replacement."
Because of the nature of their operation, non-moving
parts on shot blasters are subject to wear by the shot media itself.
The wheels, impellers, paddles, baskets and baffle plates, as
well as the doors and walls of the centrifugal airless cabinets,
are all exposed to the abrasives. Frequent visual inspection and
maintenance is imperative for this equipment. "The impeller
blades, protective deflectors, housing and all inside parts should
be checked for wear weekly," Kansas Instruments' Wessel advised.
All moving parts require some form of regular
maintenance. Boomgarden said the frequency and degree of maintenance
will vary depending on use, location and whether or not the moving
part is exposed to a wet environment. "Naturally, moving
parts, such as chains or gears which are constantly being exposed
to water will require more maintenance because the lubricants
get washed away," he said. "Here again, the manufacturer
will suggest a proper maintenance schedule for most moving parts."
And don't forget to inspect pumps on the equipment.
Today, most pumps are an impeller type pump," Boomgarden
said. "These require very little maintenance other than greasing
bearings once a month."
Belts and hoses
Goff's Zehren said checking inexpensive parts
regularly will save a shop from unnecessary costs from wasted
solution and the time needed to clean up spills. "Hoses should
be checked daily for cracks," he said. "If a hose is
in anyway damaged or shows signs of wear, it should be replaced."
Boomgarden said belts need to be replaced when
they become stretched too far to be adjusted properly, break or
suffer from severe cracking/chipping due to excessive age and
Accessories for various cleaning equipment
may also help reduce maintenance costs. Betty Rickards, marketing
coordinator for Empire Abrasive Equipment Co., Langhorne, PA,
said continuous dust collectors, which optimize cleaning production
by purging dust from filtration surfaces while operating air-blast
equipment, is a very popular accessory. Rickards said the continuous
duty dust collectors, which are designed primarily for use with
manual blast cabinets, are equipped with cartridge filters to
maximize "up-time" and to simplify maintenance. "The
normal cleaning of the filters during operation is via pneumatic
reverse pulse jet cleaning," Rickards explained. "It
only takes between a few seconds to several minutes to clean the
filters, depending on how dirty they are."
Rickards said replacement of the filters depends
on the type and duration of air blasting which is being performed
in the shop. "It can be months or even years before you have
to replace the cartridge filters," Rickards.
According to Rickards, these dust collectors
capture 99.999% of particles one-half micron or larger. And besides
keeping the cleaning equipment functioning efficiently, such filtering
units have other benefits to a shop. "Because of their high
efficiency, these filters permit recirculation of the air to the
work environment, thereby reducing HVAC costs," Rickards
For aqueous equipment, Zehren said oil skimmers
and sludge conveyers are extremely beneficial when applicable.
"By removing oil and grease from the cleaning solution/water,
the machine is more effective and offers better quality results,"
said Zehren. "Parts clean in less time and the machine requires
less daily maintenance by removing this automatically from the
Other issues to consider
To prevent damaging cleaning equipment, Delores
Shaver, industrial sales manager for Ecolink, Stone Mountain,
GA, a manufacturer of environmentally preferred solvents used
in jet washers, said shop employees should be up to date on what
cleaning solutions can be used in their particular washer. "Some
solutions are not recommended for certain cleaning equipment,"
Shaver said. "Some solutions will deteriorate the equipment's
hoses or seals." Many cleaning equipment manufacturers recommend
solutions and chemicals used in their equipment contain rust inhibitors
to protect the integrity of the steel cabinets.
And regular maintenance also keeps the cleaning
equipment under a manufacturer's warranty. "Almost every
manufacturer that I'm aware of will void the warranty if certain
items are not maintained properly," The Hotsy Corp's Boomgarden
said. "Just like with any automobile, if the oil and filter
changes are not conducted on a prescribed schedule, the manufacturer
will typically state that the warranty is null and void for service
resulting from the lack of regular maintenance."
Goff's Zehren agreed, and said most rebuilding
shops are aware of the warranty issues associated with not properly
replacing wear parts to equipment. "It is the exception that
shops allow this to happen, but it can and does in our industry,"
The U.S. EPA Office of Research and Development,
Washington, DC, offers a number of additional maintenance practices
shops can perform to keep equipment in good working order.
- Rack systems should be maintained in good
condition, free from cracks, rust, and corrosion which can flake
off and contaminate the bath. Metal tanks should be properly coated
with protective finishes both inside and out.
- The float valve that supplies make-up water
to tanks of heated cleaning solutions should be maintained regularly.
While maintaining an adequate level is necessary, it is also important
that the valve does not leak and result in dilution of the cleaner.
In addition to maintenance, routine analytical checks of solution
strength are a good way to detect slow leaks. Decreases in solution
strength during a time when the tank has not been used are a sure
indication of a leaking valve (provided that the tank is not leaking).
- Screen solids before they reach the waste
sump on aqueous equipment . The majority of the heavy metal residue,
oil and grease removed from hot tank operations occurs after the
actual hot use. The heavier concentrations of solid residues are
found in the waste sump. The standard practice currently is to
use a high velocity spray wand to dislodge these solids into the
sump. Proper capture and disposal of these wastes is necessary.
This can be done by use of a solids collection tray with overflow
to the sump or periodic cleanout of the sump by a waste hauler
for disposal at a Class I landfill.
By being aware of these requirements and following
through with a regular service and inspection policy, rebuilders
can increase the production of their work, reduce costs and at
the same time extend the life of their cleaning equipment.