Kemphos 326 (Accelerator Heavy Zinc Phosphating Chemical)
(Accelerator Heavy Zinc Phosphating Process)

Product Specifications
Kemphos-326 is an accelerated Zinc phosphating process, which is specially formulated to produce medium to heavy weight coating on Iron and steel surfaces by hot immersion method. Kemphos-326 is recommended for wide range of ferrous metal articles such as car accessories, metal cores, forge and cast iron components, small component parts such as nuts, bolts etc. Kemphos-326 protects iron and steel surfaces from rusting. Medium weight coating gives a very good foundation for paint system and protects under film corrosion. Heavy weight coatings provide excellent base for stains and are also recommended for small component parts for rust protection with minimum build up on thread parts.

This process will yield a coating wt. of 7.5 gm per square meter.

Product Specifications

3.0 Product Operating Data

Degreasing
Remove all oils and greases by emulsion cleaning or by trichlorothylene vapour degreasing or by solvent wiping. Thorough rinsing should be followed, wherever necessary after degreasing.

Derusting
Remove rust and scales present on the articles to be processed by immersion in Kemklin HD. If scales are heavy the articles should be cleaned by shot blasting or by pickling. After pickling rinsing should be carried out in two stages.

Phosphating
Immerse the components in Kemphos-326 bath for 5 to 40 minutes at 80-85°C temperature. Immersion time depends on the type of coating weight required. Medium weight can be produced by immersion for 3-5 minutes which serves a good base for paints. Heavier coatings with kemphos-326 can be obtained by Immersion for 20-40 minutes, which increases corrosion resistance. Rinse the phosphate articles in cold running water followed by hot water rinse to accelerate drying.

Passivation
Articles should be persisted by immersion in Hot Kemlyte-333 solution at 70°C for 30 seconds to 1 minute.

Drying
After passivation the articles should be dried immediately drying can be done inside a hot air circulating oven or by means of compressed air.

Product Application Equipment
Kemphos-326 tank should be fabricated with 3 to 4 mm thick M.S. Plates with continuous convection current hating system.

Testing and Control Procedure

Total Acidity
Pipette out 10 ml of bath solution in a clean 100 ml beaker or conical flask and add 2 to 3 drops of Indicator Phenolphthalein and titrate against N/10 NaOH solution to a pink end point. The number of Mls. required represent the total acid pointage. Bath pointage should be maintained between 28 to 32 ml. Add 125 ml of Kemphos-326 per 100 liters of bath for each point age below 30.

Chemical Replenishment
Restore the bath to the working level by adding water to makeup evaporation loss and drag out losses. Check the Kemphos-326 pointage.