| Overview: |
Plural component proportioning
systems are self-contained epoxy paint proportioning and mixing systems.
Unlike hand mixing operations, these systems provide proper mixing and precise generation of the paint
required by an application and consequently generates minimal waste.
Epoxy paint mixtures are prepared by premixing
a base and a catalyst, and then combining them in appropriate proportions in a
separate container. After mixing and waiting the specified time,
application of the paint to the workpiece may proceed. Epoxy paint
ingredients have a limited pot life once mixed, which cannot be exceeded
without affecting the characteristics of the paint. If the pot life is
exceeded, the mixture must be disposed and the application equipment must
be cleaned with a solvent. Under conventional methods, the mixture is
prepared by hand. This frequently results in the generation of excess
paint, which requires solvent cleanup and disposal of the paint and
solvent as a hazardous waste.
Proportional paint systems are also suitable
for polyurethane paints and should have many of the same benefits of epoxy
paint mixtures. An additional benefit is that since the mixing is
automated it also tends to be more accurate and consistent than
conventional mixing systems.
Plural component proportioning systems are
used in conjunction with application devices. The proportioning and
application system layout typically includes the following components: 1)
proportioning pump module, 2) mix manifold, 3) mixer, 4) application
device, 5) material supply module, and 6) purge or flush module. These
systems optimize painting operations by maximizing efficiency and
minimizing waste generated.
The plural component proportioning system for
epoxy paints provides total control of materials from container(s) to the
application. They are accurate and can provide more consistent material
quality than hand mixing. These systems can also keep pace with higher
production requirements. They mix on demand (i.e., as the gun is
triggered), which results in no significant quantities of wasted
materials. Material cleanup requires less labor and maintenance, and
generates less waste because the mixed material can be purged with solvent
from the mix manifold, mixer, hose, and applicator before it cures. The
plural component proportioning system is a closed system and as a result,
there are fewer spills, less contamination or waste to clean up, and less
contact between personnel and potentially hazardous materials. In
addition, the proportioning system makes bulk purchase of material
practical.
If an epoxy paint requires a significant
induction time (15 minutes or longer), the plural component proportioning
system can still be used, provided that the mixed paint is allowed to
stand in a separate container prior to application.
A PrecisionMixTM (P-Mix) controller
for the plural component proportioning system may also be implemented. The
P-Mix controller is an electronic system that continuously mixes resin and
catalyst at a pre-selected ratio in small batches, delivering the mixed
material on command. The P-Mix can detect ratio problems and prevents
off-ratio coatings from being applied. This often results in a significant
reduction in rejection rates. The P-Mix system also reduces the time
required for color changes, because the required mix ratios are entered
electronically. All materials are contained in the system; the electronic
control allows color changes and flushing to take place without exposing
the operator to hazardous materials. The P-Mix system can also generate
hard copy reports for environmental and product usage information. Some of
the operating parameters reported are flow rate, mix ratio, resin usage,
catalyst usage, and solvent usage.
No new waste streams are generated using
Plural Component Proportioning Systems as compared to conventional
methods.
|
| Compliance
Benefit: |
Use of an automated process to mix
epoxy paint immediately prior to using the plural component proportioning
system reduces the volume of chemicals used and waste generated. The
process provides for the following compliance benefits:
- Reduces emissions of volatile organic compounds (VOCs) from solvent
cleaning. VOCs are associated with the formation of smog and are
typically regulated by federal and state agencies as well as local air
pollution control districts.
- Reduces emissions of hazardous air pollutants (HAPs) from solvent
cleaning. HAPs are regulated by federal, state, and local regulations
including the National Emissions Standards for Hazardous Air Pollutants
(NESHAPs) (40 CFR 63).
- Reduces generation of waste cleaning solvents and waste paint that
must be handled and disposed as hazardous waste under 40 CFR 260
and related sections.
- Reduces hazardous materials usage as required of federal facilities
by Executive Order (EO) 13148, Greening the
Government Through Leadership in Environmental Management.
- Reduces storage and use of substances that are regulated by SARA
Title III (TRI, Tier I /Tier II) if certain thresholds are exceeded
(40 CFR 355, 370, and 372; EO 13148).
- Reduced occupational exposures that are regulated under 29 CFR
1910.
Compliance benefits include: 1) reduced recordkeeping and reporting requirements under the Clean Air Act Title V Operating
Permit Program, NESHAPs, and SARA programs; 2) reduced administrative burden associated with
hazardous waste (i.e., tracking, plans, reports, training); and 3) reduced administrative
burden associated with OSHA (i.e., training and recordkeeping).
The compliance benefits listed here are only
meant to be used as general guidelines and are not meant to be strictly
interpreted. Actual compliance benefits will vary depending on the factors
involved, e.g., the amount of workload involved.
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| Materials
Compatibility: |
Material specification data
for the epoxy paint materials needs to be evaluated, with respect to the
proportioning and application system components, prior to specification of
the actual system to ensure material compatibility. The materials used for
the pumps and packings need to be evaluated on a case-by-case basis.
Stainless steel and Teflon® components do not pose
compatibility problems with most materials used in epoxy paint operations.
|
| Safety and
Health: |
Health concerns depend on the
variety of paint that is used. The use of polyurethane paints requires
implementation of precautions associated with isocyanates. Inhalation of
lead- and zinc chromate-based paints can lead to irritation of the
respiratory system. Some lead compounds are carcinogenic. Solvent-based
paints can irritate the lungs and mucous membranes. Prolonged exposure can
affect respiration and the central nervous system. Proper personal
protective (PPE) equipment should be used. These safety and health issues
are also applicable when using conventional methods.
Consult your local industrial health
specialist, your local health and safety personnel, and the appropriate
MSDS prior to implementing this technology.
|
| Benefits: |
-
Plural component proportioning system provides total control of
materials from container to application.
- Paint is generated on an as-needed basis, eliminating the generation
of excess paint. Under conventional methods, this excess paint is
frequently disposed as hazardous waste.
- Plural component proportioning systems are effective for many
two-component paint systems besides epoxy paints, such as polyurethane
paints.
- The use of cleanup solvents is minimized.
- Less potential for spills.
- Less contact between personnel and potentially hazardous materials.
- Cost savings associated with buying paint in bulk.
|
| Disadvantages: |
- Plural component proportioning systems need to be designed for
specific applications.
- Plural component proportioning systems are only effective where
production utilizes significant quantities of paint and where color or
types of coating are not changed routinely.
|
| Economic
Analysis: |
Capital costs for plural component
proportioning systems can range from $50,000 to $70,000 for systems that
mix multiple materials or $6,000 to $7,000 for basic units that mix two
materials. Application systems are additional and their capital costs can
range from $500 to $5,000. Each application needs to be evaluated on a
case-by-case basis with respect to material and labor costs and
savings.
The following is an example of the replacement
of a hand-mixing paint operation with a relatively simple Plural Component
Proportioning System.
Assumptions:
- Annual paint usage for hand mixing system: 4,000 gals.
- Annual solvent usage for hand mixing system: 2,250 gals.
- Annual labor required for equipment cleaning using hand-mixing
system: 250 hrs.
- Annual solid paint waste generated using hand-mixing system: 5,500
lbs.
- Paint cost: $85/gal.
- Solvent cost: $7/gal.
- Labor rate: $45/hr.
- Paint solid waste disposal at $1/lb.
- Solvent waste disposal at $3/gal.
- All solvent is disposed as waste.
- Plural component proportioning system reduces paint usage by 15%.
- Plural component proportioning system reduces solvent usage and
waste by 50%.
- Plural component proportioning system reduces labor usage by 50%.
- Plural component proportioning system reduces paint waste by 50%.
Annual Operating Cost Comparison for Plural Component
Proportioning System and Hand Mixing System
|
|
|
|
Operational Costs: |
|
|
|
Labor: |
$5,600 |
$11,300 |
|
Paint and Solvent: |
$296,900 |
$355,800 |
|
Waste Disposal |
$6,100 |
$12,300 |
|
Total
Costs: |
$308,600 |
$379,400 |
|
Total
Income: |
$0 |
$0 |
|
Annual
Benefit: |
-$308,600 |
-$379,400 |
Economic Analysis Summary:
- Annual Savings for Plural Component
System: $70,000
- Capital Cost for Diversion Equipment/Process: $15,000
- Payback Period for Investment in Equipment/Process: <1 year
Click Here to
view an Active Spreadsheet for this Economic Analysis and Enter Your Own
Values. To return from the Active Spreadsheet, click the Back
arrow in the Tool Bar.
|
| NSN/MSDS:
|
None identified.
|
| Approving
Authority: |
Appropriate authority for making process changes
should always be sought and obtained prior to procuring or implementing any of the
technologies identified herein.
In the Air Force, approval authority is local
and does not require engineering approval. The authorization for use of this equipment is being
added to T.O.1-1-8.
|
| Points of
Contact: |
For more information
|
| Vendor: |
This is not
meant to be a complete list, as there may be other suppliers of this type of equipment.
Graco Inc.
P.O. Box 1441
Minneapolis, MN 55440-1441
Phone: (800) 367-4023
FAX: (612) 623-6777
ITW Industrial Finishing
195 International Blvd.
Glendale Height, IL 60139
Phone: (630) 237-5000
FAX: (630) 237-5011
URL: http://www.binks.com/
Fluid Air Products (Government Distributor)
12834 Gravois Road
St Louis, MO 63127
Phone: (314) 729-7000
FAX: (314) 729-7099
Contact: Mr.Bob Hunt
E-mail: bhunt@fluidair.com
|
| Related Links: |
Plural
Component Paint System - Navy P2 Equipment Program Book
Plural Component
High and Ultra-High Solids Paint Systems - Navy P2 Equipment Program
|
Source(s):
|
Mr. Jeff Smith, DeVilbiss
Ransburg Industrial Liquid Systems.
Mr. Carl Springer, Binks
Manufacturing Company.
Mr. Vern Novstrup, NFESC,
November 1999.
|
| Supplement: |
Picture of Plural
Component Paint System
Schematic of Plural Component Paint System
|
