Answers to Common Application Questions
The following Questions and Answers are typical of the
information our sales engineering staff cover
with each new customer.
- WHAT TYPE OF CHEMICALS ARE USED?
Almost all of the cleaning solution (95%-98%) is plain
tap water. The
remaining portion is typically based on sodium metasilicate (alkaline) or
Recently developed detergents, including citrus-based or
synthetic compounds, have in many cases, successfully replaced hazardous and
now, illegal, solvents.
The use of stainless-steel construction increases the range of
cleaning materials, even allowing the use of
de-ionized water (for spot-free parts) and mildly acidic solutions for cleaning &
phosphotizing prior to painting.
The KEY POINTS of aqueous-based cleaning solutions are cost savings,
environmental and operator safety.
- HOW LONG DOES THE SOLUTION LAST?
The Roto-Jet Parts Washer incorporates a "closed-loop design, better described
as "self-recirculating"; i.e., no continuous discharge of spent wash
solution, such as you would have with a "dishwasher". The cleaning solution is
constantly screened and re-circulated with optional micron-level filtering
After the initial "charging" of the unit with water and the appropriate amount
of detergent, only minimal additions of water and detergent are necessary to
maintain a proper solution chemistry. In many cases, the solution can last
for weeks or months if additional steps such as oil skimming and filtering are
- DO I NEED TO USE A CHEMICAL OR DETERGENT?
Almost always the answer is "yes", especially with units made of carbon steel.
Besides surfactants to speed up the cleaning process, the "detergent" will
also have anti-foaming compounds and inhibitors to prevent rusting of your parts
and your cleaning equipment.
- ARE THE WASTES HAZARDOUS?
In most cases, the answer is "yes".
Although most modern cleaning chemicals ARE "biodegradable" when mixed with
water in normal concentrations, it's usually the material being removed
that causes the solution to be classified as hazardous (within various degrees).
If your waste stream contains heavy metals or toxic compounds (such as cadmium),
then your waste is definitely hazardous and we strongly recommend
contacting the appropriate local, state, federal agencies for specific details
on satisfying your particular waste handling requirements.
Your local waste hauler is also a good source of information and can in many
cases, be of invaluable service in helping you meet any "cradle-to-grave"
- WHAT ABOUT WASTE DISPOSAL?
Several methods with varying degrees of convenience, speed and economy are
available when changing spent solution.
The easiest is to have a waste-removal firm pump the unit out. This has the
advantage of speed and convenience but can be costly.
A slower, but more economical procedure, involves pumping the solution out of the
unit into suitable containers, allowing particulate material to settle and then
pumping the clarified solution back into the unit.
This method has the cost advantage of re-cycling almost all of the water and
chemicals in the cleaning solution.
The best balance between speed and cost usually involves the use of some sort of
evaporator to condense the spent cleaning solution, then having the concentrate
NOTE: With environmental focus narrowing down to smaller companies, the
days of being able to dump the solution into a floor "clarifier" and then into a
Publicly Owned Water Treatment facility are rapidly disappearing.
The appropriate local, state and federal agencies should be contacted before
discharging any waste stream.
- CAN I USE NON-FLAMMABLE SOLVENTS?
NO. The unit is designed for water-based cleaners only. Any detergent used in
the unit MUST have built-in defoamers and especially if built of carbon steel, built-in rust
- WILL I NEED A RINSE CYCLE?
Many cleaning operations do not require the additional step of rinsing as there
is normally very little residue left on the parts once cleaned.
In fact, if your parts are iron or steel, rinsing can negatively impact
your parts by removing the rust inhibitors that have been deposited on them by
the cleaning solution.
This process (of the detergent's rust inhibitors being taken out of the unit
while on the parts just cleaned) is called "drag-out" and is one of the reasons
why regular additions of fresh detergent is necessary.
Some applications, on the other hand, DO require a relatively spot-free surface
and in these instances, rinse stages can go from rinse-to-drain to fully
re-circulating stages and stainless-steel construction to allow the use of
- HOW LONG WILL IT TAKE TO CLEAN MY PARTS?
This depends entirely on what's being removed. Light oils, machining coolants,
and /or normal shop grime typically take 1-5 minutes. Heavy oils,
stamping compounds, grease can take 5-10 minutes. Rust, paint, adhesives,
decals can take 15-20 minutes.
CLEANING TIME DEPENDS ENTIRELY UPON THE DESIGN OF
THE UNIT AND WHAT THE CUSTOMER
NEEDS TO MEET PRODUCTION REQUIREMENTS.
Units have been built to entirely strip the carbon, dirt and oil from
automotive heads within 1 minute. The design called for 75 HP motors,
parts racks with chain tie-downs, etc. Other parts were so large that the
best approach was for the wash manifold to travel around the part.
There are usually several ways to quickly and efficiently
clean your parts. Factors such as existing parts handling, subsequent
processes, and even machine location often determine which style of parts
washer might work the best for a cleaning application.
- WHAT'S SO SPECIAL ABOUT THE SPRAY MANIFOLD?
The optional Roto-Jet "Impactt-2" wash manifold uses custom-made, high-impact and clog-resistant jets
press-fitted into a standard screwed-pipe manifold. The direction of the
spray is adjustable by turning the pipes.
The design and effectiveness of the wash manifold is one of the main features of
Roto-Jet units. With it’s full 3600 wrap-around configuration,
off-shoot arms (most units), end-cap debris removal valves, 1.5”
center-to-center ImpactJETT spacing and virtually lifetime wear-proof
design, a Roto-Jet Parts Washer out-performs most other washers with three times
the horsepower and does it in one-fourth the time!
Watch a 1-minute cleaning demo here -->
- WILL I NEED TO VENT TO THE OUTSIDE?
- A quantity of water vapor is created as the unit operates. In buildings with a
high ceiling this is normally not a problem. If the location has a low
ceiling or if additional humidity in the immediate surrounding is objectionable,
then the Roto-Jet can be ordered with a power-vent option.
- HOW LONG DOES THE UNIT TAKE TO HEAT UP?
The initial heat-up time varies with the model size but normally takes from
1-1/2 to 2 hours for the initial heat-up. Once the solution and cabinet
are hot, minimal re-heating is required.
- WILL THE PARTS BE DRY AFTER WASHING?
After washing, the parts are usually at the temperature
of the cleaning solution and will rapidly air dry once removed from the wash
chamber. As an option, a hot or a cold blow-off system can be installed.
The cold blow-off system uses available compressed air and is designed to
remove solution from catch areas on the parts. The hot blow-off system
uses heating elements and a high-velocity fan to rapidly air-dry larger parts.
An additional benefit to either blow-off system is that of functioning as a
vapor exhaust system.
- WHAT ABOUT PARTS AND CUSTOMER SUPPORT?
Roto-Jet of America Company, Inc. still provides parts and support for units
that are over 30 years old. You'll find our after-sales support to be one
of the best in the industry. If our technical staff cannot rapidly resolve
a problem with your unit, we can usually recommend a local professional whom we
will work with to get you
back-on-line as soon as possible.