Alkzinc 818. Mirror bright finish Good zinc deposit distribution Very good adhesion and ductility Excellent chromate receptivity

Transcription

1 Zinc Plating Systems Pavco s process is an alkaline zinc brightener system that offers mirror bright deposits that do not dull or fade during high temperature baking. The deposit easily accepts all chromate conversion coatings. Mirror bright finish Good zinc deposit distribution Very good adhesion and ductility Excellent chromate receptivity Non-cyanide Temperature tolerance up to 43 C, reducing cooling costs PAVCO, Inc John Crosland Jr Drive Charlotte, NC Phone: Toll-free: or PAVCO INC ( ) Fax: Order Fax (for orders only)

2 2 Zinc Plating System Operating Parameters Barrel or Rack: Range Optimum Zinc: g/l 7.5 g/l Sodium hydroxide: g/l 150 g/l Starter 1-2% 1.5 % ener % 0.075% EDTA g/l 0.75g/l UltraPure % 0.1% or as needed Current density ASD 0.5 ASD Equipment: Tank: Generator tank: Anodes: Anode S-Hooks: Anode Bars: Filtration: Rectifier: Temperature: Control: Ventilation: Agitation: Optional Equipment: A low alloy steel tank is required. Consult Pavco for design parameters. Low alloy steel. Nickel plated S-hooks. Use copper anode bars, preferably shielded with plastic. Use 5-15 micron polypropylene disks or cartridges. Filtration speed should be at least 1 tank turnover per hour. Up to 18 volts for barrel and up to 12 volts for rack. The system is tolerant to temperatures ranging from C. A steel or stainless steel heat exchanger is recommended for both cooling and heating. Recommended. Air agitation is not recommended. Automatic brightener feeder, automatic temperature control. Maintenance of the Solution: Zinc Sodium hydroxide Starter ener By analysis, control with generator tank By analysis By drag-out & hull cell 1liter/ 7,500-10,000 amp hrs Bath Makeup per 1000 Liters: 1. Fill a steel tank with 700 liters of water. 2. Dissolve 70 kg of sodium hydroxide in the water. 3. Add 50 liters of Zincate concentrate (ZB 1300). 4. Add 15 liters of Starter. 5. Add and mix in 0.75g/l EDTA. 6. Add 1 liter Ultrapure. 7. Add warm water to the 1,000 liter level. 8. Add ener only if the first parts require it.

3 3 Zinc Plating System Additional Agents: Alkaline Zinc Wetter: UltraPure : EDTA: Use at 0.01% by volume if misting becomes a problem. Use at 0.1% by volume if purifier is needed. Use 0.25g/l as needed. Analytical Procedures: Zinc Reagents: 1. Acetate Buffer - Make this by dissolving 180 grams of sodium acetate into 500 mls de-ionized water. Add 30 mls of acetic acid and add de-ionized water to 1 liter of solution. 2. Xylenol Orange Indicator Make this by dissolving two grams of Xylenol Orange in one liter of de-ionized water M EDTA Procedure: 1. Into a 400 ml beaker pipette a 5 ml bath sample. CAUTION: Fumes are poisonous if using this method with a cyanide bath. 2. Add 150 mls de-ionized water. 3. Add 5 mls of 30% hydrochloric acid. 4. Add 50 ml acetate buffer. 5. Add indicator 6. Titrate with 0.1M EDTA until the color changes from red to yellow. Calculation: ml of titration 1.32 = zinc in g/l Sodium hydroxide analysis Reagents: 1. Indigo Carmine Indicator 2. 1N acid Procedure: 1. Pipette a 5 ml bath sample into a 125 ml Erlenmeyer flask 2. Add 10 mls de-ionized water. 3. Add 5 drops of Indigo Carmine indicator 5. Titrate with 1N acid until the color changes from yellow to blue. Calculation: (ml of titration x 7.49) + g/l zinc = sodium hydroxide in g/l Hull Cell Test: Agitation: Temperature: Current & Time: 267 ml Hull Cell Still or no agitation Operating temperature 1 amp /10 minutes for barrel

4 4 Zinc Plating System Normal Hull Cell High Current Density Problem Crystal Normal Low Starter Low Current Density Problem Chrome Contamination Gray Metal Contamination Problem Black (After Dip) Metallic Contamination Add UltraPure Metallic Contamination (Pb, Cu, or Fe) High Current Density Problem Skipped Plate HAZE or Semi- Skip Organic Contamination or High Particulate Level High ener Chromium Contamination Troubleshooting Chart: Problem Cause Possible Solution Slow plating speed (efficiency) Low zinc / high Starter Low temperature Poor filtration Over-pickling Load size too large Electrical problems CN contamination Raise zinc Raise temperature Improve filtration Reduce time or concentration Reduce load size Check contacts, anodes, etc. Add hypochlorite per Pavco s instructions Dull in low current density Low ener Add ener in 0.025% increments Poor filtration Metallic impurities Low or high temperature Improve filtration Add 0.1% UltraPure up to two times and/or electrolyze Adjust temperature to the

5 5 Zinc Plating System High zinc level Low current High brightener consumption High temperature Heavy drag-out Bath contamination High anode current density recommended range Lower zinc Increase current Lower temperature Minimize drag-out Electrolyze, carbon treat and filter Increase anode area Caustic spray Lack of a foam blanket Add Wetter at 0.01% Current too high Low efficiency Reduce current Raise zinc, raise temperature Surface tension of solution is low Add 1 liter Additive 1935 per 1,000 liters of plating bath Rough zinc deposit Suspended particulates Improve filtration Current too high Zinc metal content decreasing Low steel area in generator Low caustic Reduce current Increase steel area Increase caustic Poor flow through generator tank Improve flow Zinc metal content decreasing Low steel area in generator Low caustic Increase steel area Increase caustic Poor flow through generator tank Improve flow Blistering or poor adhesion Poor cleaning Improve cleaning cycle Overall dullness with no brightener response Poor bath chemistry High ener Bath contaminated with metallics Bath contaminated with organics Poor quality anodes Analyze and make additions Electrolyze or zinc dust treat Electrolyze or zinc-dust treat Treat with carbon and filter Use SHG 99.99% zinc anodes Low UltraPure Add UltraPure in 0.1% increments Grease/oils or other organic impurities High particulate level High Starter or low zinc level Poor water quality Carbon treat and filter Filter Hold Starter and increase zinc level Add 0.25g/l EDTA

6 6 Zinc Plating System Waste Treatment: Dispose of the concentrates or solutions thereof according to local waste treatment regulations. Safety: Handling Pavco mandates that the following safety equipment be used when handling chemicals in an electroplating environment: safety glasses, face shield, plastic or rubber apron, rubber gloves and safety shoes. Chemicals should only be handled by trained and experienced personnel. Storage Store Pavco products in a clean, well ventilated room which temperature remains above 45 F (7 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 Alkzinc 818 Starter or ener freezes during shipment or storage, warm the product to 120 and mix it well before use. Emergency Procedures Refer to the MSDS for detailed emergency procedures. Eye Contact Seek immediate medical attention. Flush the eyes with water for 15 minutes. Skin Contact Remove all contaminated clothing. Wash the skin with soap and water. Seek medical attention. Inhalation Remove the person to an area with fresh air. Seek medical attention if necessary. Ingestion Seek immediate medical attention. Spill Dike the area to contain the spill. Refer to the MSDS for clean-up. Notify the proper authorities if required. *NOTE: Refer to the MSDS for detailed emergency medical procedures. Product Description & Shipping: Starter ( ZB1531) is a pale yellow liquid with a specific gravity between 0.99 and 1.02 and ph between 9.0 and ener ( ZB1532) is a colorless liquid with a specific gravity between 0.99 and 1.02 and ph between 4.5 and 8.5. UltraPure (ZB1630) is a yellow opaque to colorless opaque liquid. The specific gravity is between with a ph greater than Alkaline Zinc Wetter (ZB270) is a clear colorless to pale yellow liquid. The specific gravity is between with a ph greater than 9.5 All products are available in 5 gallon containers and 55 gallon drums. Revised Date: 5/27/2015 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.