Kemphos-335 (Zinc Phosphating Chemical)
(Zinc Phosphating Chemical Operated at Low Temperature)

Product Description
Kemphos-335 is an accelerated zinc/nickel based low temperature immersion/Phoshating process, which produces light to medium weight phosphate coating on Iron and steel surfaces. The coating produced by Kemphos-335 serves an excellent base for paint and coating formed after surface condition with our (Acitivtor-Kemphos-338), Pre dipping is of fine crystallien structure and gives good gloss to the paints. Kemphos-335 phospahting process gives medium weight coating and protects iron and steel surfaces against rusting and prevents formulation of rust under the paint film. Kemphos-335 bath requires faster rate of desludging to avoid pathcy coating.

Kemphos-335 meets to the requirements of IS:3618:1966 class B/C and WPN/GEN/3 class II/II accelerated processes.

Product Specifications

Product Operating Data

Product Operating Procedure

• Degreasing
• Water Rinsing
• Derusting (Kemklin)
• Water Rinsing
• Activator (Kemphos-338)
• Phosphating (Kemphos -335)
• Water Rinsing
• Passivation (Kemlyte -333)
• Drying
• (For 100 liters of bath)
• Fill the tank 2/3 with water and add 3.5 liters of Kemphos-335
• Fill the tank to the operating level and stir the solution well.
• Adjust the pH value of the bath 2.6 -3.1 by adding are over neutralizer to the bath.
• Prior to process commencement, add 25 gm. Of accelerator 002 diluted with water in the phosphating bath solution.

Product Application Equipments
Kemphos-335 tank should be fabricated with 3 to 4 mm thick M. S. plates with continuous current hating system.

Testing and Control Procedure

Total Acidity
Pipette out 10 ml. Bath solution in a conical flask. Add a few drops of Indicator Phenolphthalein. Titrate with N/10 sodium Hydroxide until permanent pink colour appears, bath pointage should be maintained between 21 – 25 ml. Adjust the pointage by adding kemphos-335 to the bath. For each pointage less add 1.35 ltr of of Kemphos-335 per 100 litres of bath.

Kemphos-002(accelerator) Test by starch – iodide paper
Dip a piece starch Iodide paper in the bath. After few seconds colour indicate the concentration of the bath.
Check up the bath temperature first.
Dip a piece of starch Iodide paper in the bath. After few seconds colour indicate the concentration of the bath.

It is very much important to have the correct amount of Accelerator in the bath. Excessive accelerator in the bath will cause excess sludge formation and wastage of Kemphos-335 insufficient addition cause accumulation of Iron salts and throws the bath out of balance.

Kemphos-002 (accelerator) Test (Titration Method)
Pipette out 50 ml bath solution into flask add 5 ml of concentrated H₂SO₄ and mixed it well. Titrate it against with N/10 KmNO₄ solution to a pink colour which will persist for few seconds.

Normal limits for Kemphos-002 (accelerator) titration is 2 – 6 ml. Lower limit is preferable. Prior to titration starch iodide paper should be positive. For 100 liter of add 10 gm Kemphos-002 (accelerator) ded to increase the accelerator pointage by 1 ml.

• pH value of the bath solution can be determined with the help of pH meter by universal pH indicator solution.

• pH value of the bath solution be kept in the specific limit (I.e. 2.6 -3.1) in order to get more uniform and compact phosphate coating alone do not protect the rusting for a long time and require seating with paint, stainor and oil immediately after the coating which provide permanent protection.

Ferrous Iron Contents
Pipette out 10 ml of the bath solution in 150 ml conical flask. Add 2 ml or 50% H₂SO₄ and titrate with N/10 KmNO₄ (3.16 gm/ltr) solution to pink end point persisting for 15 seconds. Multiply by the titration reading with 0.56, we get percentage of Ions in the bath.

Chemical Replenishment
Restore the bath to the working level by adding water to makeup evaporation loss and drag out losses. Check the Kemphos-335 pointage.

Safety Measures
Kemphos-335 is an acidic liquid material, and while handling proper care should be taken. Protect eyes and skin by means of goggles, aprons, gloves, etc. It comes in contact with skin and eyes wash thoroughly with flush off water and get medical advice.

General Information
Corrosion Resistance: Excellent