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Paint Circulation Technology L evel 2 - Training Document. Subject Matter Expert: Miguel Bahena. What Is A Paint Circulating System. A pressurized vessel used to transport material to various locations. More efficient then manual moving material to individual locations. What Are We Doing?.
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Paint Circulation TechnologyLevel 2 - Training Document Subject Matter Expert: Miguel Bahena
What Is A Paint Circulating System A pressurized vessel used to transport material to various locations. More efficient then manual moving material to individual locations.
What Are We Doing? Moving material from point A to point B. Supply material fluid pressure. Supply material fluid flow. Maintain material integrity. That is all we do! Sounds simple doesn’t it?
What Are We Doing? Point A Point B
PAINT MIX ROOM • The martial that is used for painting the vehicles is a solvent borne material which is extremely flammable. The paint is stored and pumped from a paint mix room. • MIX ROOMS ARE CLASS 1 DIVISION 1 AREAS – NO ELECTRIC ITEMS ARE ALLOWED IN THIS ROOM INCLUDING – (CELL PHONES, FLASH LIGHTS, RADIOS, ETC). UNLESS APPROVED BY FORD SAFETY Tote storage rack Tote stand for loading material Bulk Storage Tank for Solvent and Waste Typical circulation system Typical paint mix room
Typical Paint Circulation System Components Transfer Pump Surge Chamber Day Tank BPR Pump Supply Line Tote Tank Return Line Booth Drops Heat Exchanger
PAINT CIRCULATION HEADER • The paint is pumped from the paint circulation module to the spray booths in what is called a header system. The headers system is constructed from stainless steel pipe/tubing and delivers paint to each robot or manual spray station. • At each robot or manual station, a line tee’s off the header to feed this station. This is called a drop/paint station. Typical paint circulation header
PAINT HEATEXCHAGNER SYSTEM • The paint must be applied to the vehicle at the correct temperature. A paint heat exchanger system is used to maintain a temperature of +/- 2 degrees F Tube and shell heat exchanger Water supply and return lines Water conditioning skid
WASTE COLLECTION SYSTEM • Each time the robot or manual station changes color a certain amount of waste is generated. This waste is collected at the paint booth in a waste collection system. Special Waste Collection Funnel Under Cap Cleaner to Flush Drop Legs and Prevent Debris from Entering Waste Header Recirculation of the header and drop legs are very important Gravity Waste Header Fabricated from 2” S.S. Tubing Utilizing Sanitary Fittings for Smooth ID and Ease of Maintenance. Line Installed at ¼” – 3/8” per foot to maintain proper drain velocity Ball Valves Added to Header to Have the Ability to Power Flush Header for Preventative Maintenance Purge Solvent Piped to Tank so Virgin Solvent Can be Added for Cleaning. A Catalyst Stop can be Substituted to Prevent the Catalyst from Curing (paint supplier can recommend material) Special Cage Inside Tank to Capture 2K Waste Debris From Clogging Pumps Utilize (1) Pump for Recirculation and (1) Pump for Empting of the Tank Note: Containment Pan Not Shown
Supply Material Fluid Pressure? • Generally between 80-100 PSI at the drop and 20-60 PSI at the point of atomization.
Circulating systems must provide minimum required fluid pressure at all drops. As material flows through piping friction causes a “pressure loss”. This pressure loss must be calculated in order to ensure the last drop meets the minimum pressure requirement. Pressure calculations are done via the “Delta P Formula”. Supply Material Fluid Pressure?
DELTA P FORMULA P Q V L FORMULA ~ = .0273 4 ID ~ “Change” P ~ “Pressure” (Pounds per Square Inch) Q ~ “Quantity of Flow” (Gallons Per Minute) V ~ “Viscosity” (Poise) L ~ “Length” (Feet) ID ~ “Inside Diameter” (Inches)
DELTA P FORMULA Example: Calculate Pressure Lost Between Drop 1 & Drop 2? 50 Feet 1” x .065 WALL - 18 GAUGE S.S. TUBING Drop 1 Drop 2 Viscosity = 1 Poise Quantity = 1.84 GPM (1 foot per sec) Length = 50 Feet I.D. = .87 Inches (1” x .065 Wall S.S. Tubing)
DELTA P FORMULA • Substitute numbers into formula P Q V L FORMULA ~ = .0273 4 ID P 1.84 * 1 * 50 FORMULA ~ = .0273 4 .87 50 Feet Drop 2 Drop 1 1” x .065 WALL - 18 GAUGE S.S. TUBING P = 4.384 psi
Maintain Material Integrity? This is the #1 concern for paint circulating system design. Issues include: Material velocity Shear (turns through system) What Are We Doing?
Material Velocity Material must maintain a certain velocity through all piping and drop hoses. “Velocity” is measured via ft/sec of material flow through piping and drop hoses. General rule is WB material must maintain 0.5’/sec and SB 1’/sec. Maintain Material Integrity?
Maintain Material Integrity? Material Velocity
Material Velocity If velocity is to low then material can settle. If material settles finished product can have the “appearance” of dirt when in fact it is a settling issue. Over time this can also lead to restricted or clogged lines (usually return lines). Maintain Material Integrity?
Material Velocity If velocity is to high then extra energy is being used and material shear levels are higher then necessary. Higher velocity equates to higher then necessary pump flow rates and turns through paint circulating system. Maintain Material Integrity?
Maintain Material Integrity? Shear Shear is caused at any point where force is put on material. High pressure combined with high flow will cause the highest shear point (i.e. BPR, pump ball checks, regulators…). The lower the pressure and/or flow the better.
Shear General rule is after 1000 turns through the system material will have visible color degradation. Material must be replenished or it could be damaged beyond repair. 80/20 Theory: 80% of paint waste costs comes from 20% of material (i.e. low run colors). Maintain Material Integrity?
Maintain Material Integrity? Material Integrity Example
What Are We Doing? Supply Material Flow? Total system flow is based on the following: • Total applicator flow requirements if all applicators are flowing at maximum rate at one time. OR • Required material velocity flow rate needed to maintain material integrity. WHICHEVER IS HIGHER
TYPES OF PAINT CIRC SYSTEMS What are end user options? • THREE PIPE SYSTEM • TWO PIPE SYSTEM • ONE PIPE SYSTEM • PIGGABLE SYSTEM
3-Pipe Systems ~ Advantage: • Circulation thru Color Valve • Color valve can be mounted on robot arm (low material waste) ~ Disadvantage: • Time and material to clean • Old Technology – Does not work well with WB Paints • Regulator Dependent – Have to adjust to make sure system is balanced • Different velocities throughout system • Costly labor to design & install • Not easily expandable • Swings in viscosity can cause problems
Three Pipe System (1) Supply – (2) Returns
TWO PIPE SYSTEM • GRADUATED LINE SIZES • SINGLE BPR (Back Pressure Regulator) • RECIRCS THROUGH COLOR VALVE MOUNTED ON ROBOT ARM • HYDRAULICALLY BALANCED OR REGULATOR DEPENDANT
2-Pipe Systems ~ Advantage: • Circulation in Color Valve • Color valve can be mounted on robot arm (low material waste) • Not Regulator Dependent ~ Disadvantage: • Time and material to clean • Different velocities throughout system • Costly labor to design & install • Not easily expandable • Swings in viscosity can cause problems
ONE PIPE SYSTEM (Ring Main) One pipe circles booth. Deadend drops are used to supply color valve with material.
Overview 1-Pipe Systems ~ Disadvantage: ~ Advantage: • Low volume containment • Quick color change • Quick viscosity adjustment • Reduced energy • Easily expandable • Lower install cost • No Circulation through Color Valve • Material settling at deadend drops
Overview Piggable System ~ Advantage: • Low volume containment • No settling • Quick color change • Capable of being shut down • Expandable • Reduced energy • Circulates through color valve • Low design engineering costs • Simpler operation • Consistent velocity • Low solvent usage ~ Disadvantage: • Color valve cannot be located on robot arm (must be hard mounted)
\ PIGGABLESYSTEMS
COMPRESSED AIR HEADER SOLVENT HEADER MAIN PAINT LINE COLOR 1 COLOR CHANGE VALVE MAIN PAINT LINE COLOR 1 MAIN PAINT LINE COLOR 1
Paint Circulation System Components Transfer Pump Surge Chamber Day Tank BPR Pump Supply Line Tote Tank Return Line Booth Drops Heat Exchanger
TYPES OF BALL VALVES • Non-Encapsulated Ball Valves • Dirt builds up between ball • Not easily cleanable • Paint can settle out • Cheaper • FORD SPEC - Full-Encapsulated Ball Valves • No space for dirt build up • Easily cleanable • Piggable • More Expensive
TYPES OF FITTINGS • Threaded Fittings • Dirt builds up threads • Rough inside diameter • Oil used to cut threads • Not piggable • Sanitary Fittings • Used in dairy and pharma industry • Cleanest fitting • No oil used in fabrication • Piggable
DUAL FUNCTION FILTERS Cartridge Basket Strainer Filter Housing Bag Centering Ring
TYPES OF AGITATORS • Vain Air Motors • High SCFM usage (15 – 30 scfm) • High cost to operate • Oil required for lubrication • Radial Piston Air Motor • Low SCFM usage (2 – 4 scfm) • Low cost to operate • Oil NOT required for lubrication • FORD SPEC - Electric Direct Drive Agitator Motor • Lowest cost to operate • Most expensive to integrate (larger tanks)
TANKS • FLAT LID TANKS • Removal lids for cleaning • Larger access openings • Not recommended for WB – Paints • DOMED TOP TANKS • Not Removable • Typically smaller openings • Condensation builds up and wicks side wall • Recommend for WB Paints
Description E4-60 & E4-9016 & 24 GPM Main Pump Assembly Main Components • 5 HP Motor & Gearbox • Main Cam Shaft and Bearings • 4 Cylinders 8 Ball Check • Carriage and Cam Follower • Carriage Support Shaft and Linear Ball Bearing Bushes
Turbine Pump Technology Use multi stage chambers each with a “impeller” blade that centrifugally create pressure and flow. Each chamber will create shear and increase paint temperature as the impeller blade abuses material. Temperature increase demonstrates the inefficiency of the pump…temperature increase is lost energy. A large 10 to 20 HP motor is needed to supply necessary power to impeller blades. End result is a costly pump that shears material and needs a heat exchanger installed on the circulating system to function properly. Stages Impeller Blade
Typical turbine pumps will use a 10 to 20 HP motor to supply required pressure & flow. Smart Pumps will require a 1.5 to 5 HP to supply same pressure & flow. The extra “energy” required for turbine pumps is transferred into the material in the form of heat (30° to 50°). This heat transfer requires Temperature Controls to be used to cool material to an application temperature. The Temperature Controls may not be required for the Smart Pump as heat transfer is minimal (2° to 5°). If required in order to maintain material temperature due to changing ambient temperature, the footprint and energy consumption is much lower. Turbine Pump Technology
Overview Smart Pump… every Hz equals flow! Smart BPR… can be automatically energized or de-energized! End Result… Smart Circulating System
What is “SMART CIRC” Existing circulating technology maintains operating pressure 24 hours a day even though material is not in demand… SMART CIRC automatically adjusts system pressure and flow to meet the demands at the applicator!
Smart Circulating System Flow Chart A) Material Required: Signal activates BPR to preset pressure level. Pump is adjusted to “Flow” or “Pressure” mode depending on system demands. Job Queue Input • Data shows material to be “required”. • Data shows material is “not required”. PLC Smart Circ Controls B) Material Not Required: Signal de-activates BPR to fully open 0 pressure level. Pump is adjusted to maintain “Flow” mode at preset levels.
Material integrity. Pump component wear. Energy use. Consistent pressure settings (automated control). Consistent flow settings (automated control). Greater process controls. Why “SMART CIRC”