Diamante. Alkaline Plating Systems Diamante. Alkaline Plating Systems

Transcription

1 Alkaline Plating Systems process is the zinc plating industry s only proven low metal zinc plating process based on potassium hydroxide. The plating efficiency, leveling characteristics, deposit brilliance and chromate receptivity are superior to conventional alkaline zinc processes. Simply put, is the state of the art alkaline zinc plating process. v Mirror bright finish v High efficiency v Excellent zinc deposit distribution v Very good adhesion and ductility v Excellent chromate receptivity v Suitable for either rack or barrel v Not corrosive to equipment v Effective in a wide range of bath compositions v Simplified waste treatment (no chelating agents) v Temperature tolerance up to 120 F (50 C) v Excellent brightener stability and longevity v Tolerant to excessive brightener additions Pavco Inc John Crosland Jr. Dr. Charlotte, NC Phone Fax Toll Free

2 Pavco, Inc.: Page 2 Operating Parameters (For Rack or Barrel Operation) Range Optimum oz./gal. gms/l oz./gal. gms/l Zinc (Metal) Potassium Hydroxide Operating Conditions Temperature: F (16 49 C) 85 F (29 C) Average Current Density Barrel: Rack: 1 10 ASF ( A/dm 2 ) ASF ( A/dm 2 ) Addition Agents Mirage Acc % 0.2 % Refine: 1 4 % 3 % Alkaline Zinc Wetter 2 : % 0.01 % UltraPure 3 : % * 5 10 ASF ( A/dm 2 ) 15 ASF ( A/dm 2 ) * The amount needed depends on the level of impurities. Start at 0.25% and increase as necessary. 1. Potassium hydroxide (caustic potash) should be mercury cell or rayon grade, free of lead. 2. Alkaline Zinc Wetter is used to suppress caustic fumes and is usually needed only at start up. 3. UltraPure is a purifier needed only at start-up and after the zinc level climbs suddenly Equipment Tank: Anodes: Generator Tank: Filtration: Rectifier: Temp. Control: Ventilation: A regular steel tank may be used. Low ally steel strips, 6 wide and ⅜ thick. Consult Pavco for design parameters. Use a 5 15 micron filter cartridge packed with a filter aid or activated carbon. Filtration speed should be 1 to 2 tank turnovers per hour. Barrel: Up to 18 volts Rack: Up to 9 volts The system will operate up to 120 F (50 C). Pavco recommends that the tank be equipped with heating and cooling coils, where necessary, to keep the temperature within prescribed limits. Recommended. Alkaline Zinc Wetter will minimize any alkali mist.

3 Pavco, Inc.: Page 3 Maintenance of the solution Mirage Acc: 1 gal / 20,000 30,000 amp. hrs. (1l / 5,000 8,000 amp. hrs.) Refine: Per drag out (can be proportioned to potassium hydroxide adds) Potassium Hydroxide: Per analysis Zinc Metal: Controlled with a generator tank Typical Plating Cycle 1. Soak clean 2. Rinse (optional) 3. Electro-clean 4. Rinse (two station counter flow) 5. Acid 6. Rinse (two station counter flow) 7. Zinc plate Pavco s system 8. Rinse (two station counter flow) % nitric or sulfuric acid dip 10. Chromate (blue bright, yellow, olive drab or black) 11. Rinse 12. Rinse 13. Dry

4 Pavco, Inc.: Page 4 Bath Makeup per 1000 gallons-3785 liters Before making up the bath, clean and leach out the tank properly, making sure bus bars and anodes are also cleaned. Pavco recommends using Zincate solution which contains the necessary zinc and caustic. De-ionized water is preferred for makeup. After the bath is made up, electrolysis will be beneficial. Procedure (Zincate Concentrate) (Use constant agitation with each step). 1. Add water to the cleaned tank up to ~70% of the final volume. 2. Add the recommended level of Zincate concentrate. 3. Add water to ~90% of the final volume. 4. Add the recommended amount of UltraPure. 5. Add the recommended amount of Refine and Mirage Acc. 6. Analyze caustic level and adjust if needed. 7. Fill the cleaned steel baskets in the generator tank with Special High Grade (SHG 99.99% pure) zinc. 8. Add water to the final volume. Analysis Procedures Zinc Analysis * Note: Fumes are poisonous if using this method of zinc determination with a bath containing cyanide. Do not use this procedure on samples containing cyanide. Reagents 1. Acetate buffer To make up dissolve: a. 180 grams of anhydrous sodium acetate b. 30 ml of acetic acid c. Add de-ionized or distilled water to make one liter 2. Xylenol orange indicator: To make this indicator, dissolve 1 gram xylenol orange in 1 liter of de-ionized or distilled water M disodium EDTA solution 4. 30% hydrochloric acid (HCl)

5 Pavco, Inc.: Page 5 Analysis Procedures (continued) Procedure 1. Into a 400 ml beaker, pipette a 5 ml. bath sample. 2. Add 5 mls of 30% HCl. 3. Add ~150 ml distilled or de-ionized water. 4. Add 50 ml acetate buffer 5. Add sufficient xylenol orange indicator (~0.5 ml.) to give a fuchsia color (bright reddish pink). 6. Titrate with 0.1 M EDTA solution until the color changes to yellow. This changes very rapidly; proceed very slowly. 7. Calculation: Potassium Hydroxide Analysis Reagents ml. of titration X = zinc in oz/gal ml. of titration X 1.32 = zinc in g/l 1. Indigo carmine indicator (should be refrigerated) 2. 1 N acid Procedure 1. Pipette a 5 ml. sample into a 125 ml. Erlenmeyer flask. 2. Add 10 mls. of de-ionized water 3. Add 2 6 drops of indigo carmine indicator. 4. Titrate with 1 N acid until the color changes: yellow blue. 5. Calculation: Mls of acid titration = KOH in oz/gal

6 Pavco, Inc.: Page 6 Rack and Barrel Operations Pavco, Inc. s Hull Cell Scale 1 AMPS. 2 AMPS. 3 AMPS. 5 AMPS. TOTAL CURRENT 3 AMPS. 5 AMPS. PANEL EDGE Hull Cell Test: Agitation: Temperature: GM./1000 ML. 7.8 ML./1000 ML. AMPS./SQ. FT. 267 ML. OR 534 ML. HULL CELL OR 2 GM/267 ML. HULL CELL = 1 OZ./GAL. = 6.25 LBS./100 GAL. 2 ML./267 ML. HULL CELL = 0.96 FL. OZ./GAL. = 6 PTS./100 GAL. 4 GM. 534 ML. HULL CELL = 1 OZ./GAL. = 6.25 LBS./100 GAL. 4 ML./534 ML. HULL CELL = 0.96 FL. OZ./GAL. = 6 PTS./100 GAL. AMPS./SQ. FT ML. HULL CELL PANEL EDGE Current & Time: Normal Hull Cell Normal Low Current Density Problem 267 ml. Hull Cell Mechanical or air Operating temperature 1 amp/15 minutes Gray CU. FT. X 7.48 = GAL. GM/L X = OZ./GAL. OZ./GAL. X 7.5 = GM/LITER GAL. X 3785 = ML. A/SQ. FT. X = A/SQ. DM. High Current Density Problem Crystal Low Refine Metal Contamination Problem Black (After Dip) Metallic Contamination Add UltraPure Metallic Contamination (Pb, Cu or Fe)

7 Pavco, Inc.: Page 7 Rack and Barrel Operations (continued) High Current Density Problem Haze Organic Contamination or High Particulate Level High Current Density Problem Burning Low Refine or Semi - Troubleshooting Chart Skipped Plate High ener (Toner) Chromium Contamination Skip Problem Cause Possible Solution Slow plating speed Low metal or high carrier Raise metal (efficiency) Low temperature Raise temperature Poor filtration Pack filter with D. E. Over pickling Reduce time and/or concentration Load size too large Reduce load size Electrical problems Check contacts, anodes, etc. CN contamination Add hypochlorite per Pavco s instructions

8 Pavco, Inc.: Page 8 Troubleshooting Chart (continued) Problem Cause Possible Solution Dull in low current density Low Mirage Acc Add Mirage Acc in 0.05% increments Low KOH Poor filtration Increase KOH level Improve filtration Metallic impurities Add UltraPure in 0.1 % increments Low temperature <60 F (15 C) or high temperature >95 F (35 C) High zinc level Low current High temperature Poor anoding Adjust temperature to the recommended range Add Refine Increase current Reduce temperature Correct anoding Poor distribution Low Refine Increase Refine High brightener consumption Low KOH Heavy drag out Bath contamination Improper bath chemistry Increase KOH level Electrolyze, carbon treat and filter Analyze the bath and adjust to optimum Caustic spray Lack of a foam blanket Add Alkaline Zinc 1 pint per 1,000 gallons Current too high Low efficiency Check cathode and anode area See elsewhere in this table

9 Pavco, Inc.: Page 9 Troubleshooting Chart (continued) Problem Cause Possible Solution Rough zinc deposit Suspended particulates Filter the solution Current too high Zinc metal content decreasing Low steel area in generator Low KOH Poor flow through generator tank Reduce current Increase steel area Increase KOH Improve flow Blistering or poor adhesion Poor cleaning Correct cleaning cycle Poor bath chemistry Low temperature <60 F (15 C) High Mirage Acc Bath contaminated with Cr, Cd, Cu, Pb or other metallics Bath contaminated with organics Check analysis and make proper additions Raise temperature Electrolyze. Electrolyze and zinc dust treat if necessary Treat with carbon and filter Poor quality anodes Replace with SHG 99.9% pure zinc anodes Low UltraPure Add UltraPure in 0.1% increments

10 Pavco, Inc.: Page 10 Troubleshooting Chart (continued) Problem Cause Possible Solution Overall dullness with no brightener response Grease/oils or other organic impurities Carbon treat and filter High particulate level High Refine or low zinc level Filter Hold Refine and increase zinc level Black edges on work Low zinc Increase zinc level Waste Treatment High Refine Excess current 1. Mixing vigorously, reduce the ph to 9.0 with dilute acid. 2. Filter out or clarify and decant the precipitated zinc. Hold Refine additions Reduce current 3.Adjust the ph of the filtrate according to local pollution control regulations before discharge. General Safety Warning Information Caution: The plating solution is hazardous and may be fatal if swallowed. It will cause severe irritation to skin and eyes on contact. It is strongly advisable for people who handle or work with this solution to wear chemical safety goggles, rubber gloves and clean, protective outer clothing.

11 Pavco, Inc.: Page 11 General Safety Warning Information Emergency and First Aid Procedures: Refer to the MSDS for detailed emergency procedures. In case of eye or skin contact with Mirage Acc or Refine, immediately flush eyes or skin with cold water for 15 minutes. Remove contaminated clothing and obtain medical attention. Avoid inhalation. In case of ingestion, obtain immediate medical attention and refer to the MSDS. Procedure in Case of Spillage: Thoroughly wash the area with water or use Zorball on and around spillage and sweep, then wash the are with water. Special Precautions: Avoid contact with skin, eyes or clothing. Wash contaminated clothing before reuse. Do not reuse container for any purpose. For Industrial Use Only. Storage: Store Pavco products in a clean, well ventilated room which temperature remains above 45 o F (7 o C). Pavco products should remain in their original container with the lid or cap tightened. Drum pumps or pails must be clean prior to dispensing Pavco products to prevent contamination. If Mirage Acc freezes during shipment or storage, warm the product to 120 o F and mix it well before use. Refine damaged if frozen. Alkaline Zinc Wetter, UltraPure freeze during shipment or storage, warm the product and mix it well before use. Description and Shipping Mirage Acc - (ZB1521) is a clear pale yellow liquid with an SpG between 0.98 and 1.1 and a ph between Refine - (ZB1410) is a clear to slight yellow liquid with an SpG of and a ph greater than 9.0. Alkaline Zinc Wetter-(ZB270) is a clear colorless to pale yellow liquid with an SpG of and a ph greater than UltraPure-(ZB1630) is a yellow to dark yellow liquid. The specific gravity is between 1.0 and 1.1 with a ph greater than Complexor A-(DR100) is a white to tan powder/crystals. Complexor A is available in 45 lb. pails and 400 lb. drums. All liquid products are available in 5 gallon containers or 55 gallon drums. Mirage Acc and UltraPure are also available in a 275 gallon tote. Revision Date: 05/25/12 Revision Number: 5 WARRANTY AND DISCLAIMER Technical information and recommendations contained herein are believed to be reliable, however, the accuracy or completeness thereof is not guaranteed. No statement or recommendation shall constitute a representation unless set forth in an agreement in writing by the seller and manufacturer. NO WARRANTY OR MERCHANTABILITY OR WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE IS MADE. The following warranty is made in lieu of any other warranties, express, implied, or statutory. Products are warranted to be free from defects on material and workmanship at the time sold. The sole obligation of the seller and manufacturer under this warranty shall be to replace any product defective at the time sold. Under no circumstances shall the manufacturer or seller be liable for any loss, damage, expense, direct or consequential, arising out of the use of or inability to use the product. Materials shall not be returned to the seller or manufacturer without express written permission. No information or suggestions given by us shall be deemed to be a recommendation to use any product in conflict with any existing patent rights.