Product Details
HL-936 Alkaline zincate zinc cleaning agent
HL-936 Alkaline zincate zinc cleaning agent
Packing: 25kg/drum or 200kg/drum or 1000kg/drum
Â
1
HL-936 alkaline zincate zinc cleaning agent process
HL-936 alkaline zincate zinc additive is a new cyanide-free zinc brightener, containing two kinds of brightener, with leveling, bright, high temperature resistance of multiple functions. Using the brightener can simplify the application process, good process stability, simple composition of plating solution, low production cost, less corrosion to equipment, easy treatment of waste water. HL-936 brightener using process has the advantages of wide current density range, high brightness of coating, fast luminous speed, good dispersion ability and deep plating ability, allowing plating thicker coating, coating no foaming, no peeling, and suitable for hanging plating, rolling plating, low chromium, trivalent chromium passivation, is a more ideal zincate zinc brightener.
Â
2
Process formula and operating conditions
Â
Zinc Oxide
|
10--14g/L
|
Sodium Hydroxide
|
100--140 g/L
|
HL-936A Softening agent
|
10ml/L
|
HL-936B Brightening agent
|
6ml/L
|
HL-936 Cleaning agent
|
8—10ml/L
|
Temperature
|
5—45℃
|
Current density
|
1—8A/dm2
|
Cathode efficiency
|
70—75%
|
Area ratio of anode and cathode
|
1:2
|
Zinc Oxide : Sodium Hydroxide
|
1:8-12
|
Filtration
|
1-2 times/hour
|
Stir
|
Regular
|
Â
3
Tank maintenance and management
1. The newly distributed tank liquid shall be treated with HL-936 purifying agent. The tank should be analyzed regularly, fed regularly and treated regularly. Maintain proper concentrations of zinc and caustic soda in the bath, as they determine the conductivity of the solution.
(1) Less metal zinc is easy to cause charring in the high current area and reduce the overall current efficiency; When zinc content is too high, the performance of low current region will be reduced.
(2) When the content of sodium hydroxide is high, the leveling performance of the coating is slightly decreased, and the environmental odor is larger; When the content of sodium hydroxide is low, the coating ability of low current density area is reduced.
2. The bath is treated with 0.5-1.5g/L zinc powder every one to two months, filtered after 2 hours (note: zinc powder should not stay in the bath for too long), and electrolyzed for 4-8 hours with 0.1-0.2 A /dm2 current density.
Â
Â
Temperature 30℃
|
Temperature 40℃
|
HL-936A Softening agent 100-120ml/KA.h
|
HL-936A Softening agent 240-260ml/KA.h
|
HL-936B Brightening agent 60-90ml/KA.h
|
HL-936B Brightening agent 200-220ml/KA.h
|
HL-936 Cleaning agent
|
HL-936 Cleaning agent 30-50ml/KA.h
|
Â
5
Plating solution configuration method
Preparation of plating solution for zinc oxide purity requirements of more than 98% industrial grade, sodium hydroxide to use more than 95% purity of solid alkali.
1. Pour the calculated amount of sodium hydroxide into the tank.
2. Into the total volume of 1/5 of the water (with hot water in winter) quickly stir dissolved, become transparent.
3. Weigh the calculated amount of zinc oxide, water into a paste,
4. Gradually add to the hot lye with constant stirring until it is completely dissolved.
5. The plating solution in stirring slowly add water to the total volume of 2/3. (residual volume plus additive)
6. When the plating solution is cooled to 40 degrees below, add 2-3 grams/l zinc powder and stir fully for 15-20 minutes.
7. No zinc powder can be 0.2g/l of sodium sulfide instead, dissolve first, and dilute several times behind add edge stirring evenly added to the plating solution, standing for 4-8 hours after filtration.
8. Add additives according to the requirements of the process specification, electrolytic 4-8 hours under the condition of 0.1-0.2A /dm2 current density, trial production, and put into normal production after qualified products.
Â
6
Failure and correction method
Â
Fault phenomenon
|
Possible causes
|
Correction method
|
Poor dispersion
|
Insufficient additives
High zinc and low alkali, imbalance
High temperature and low current density
|
Supplement main additive
Analysis adjustment to reduce zinc anode
Increase current density
|
Coating luster uneven Yin and Yang surface
|
Insufficient brightener or poor dissolution
High zinc content
Low current density
High organic impurity
|
Add brightener and stir well
Analysis adjustment to reduce zinc anode
Increase current density
Activated carbon treatment
|
The coating is dull and dull
|
Metallic impurity
Less brightener
Excess temperature
|
Sodium sulfide or zinc powder treatment
Supplementary brightener
reduction of temperature
|
The coating is silvery white after passivation to earth yellow
|
High lead content
|
Sodium sulfide or zinc powder treatment
|
The coating is brittle and has pitted vesicles
|
Pretreatment oil is not cleaned
Excess brightener
High organic impurity
Low temperature and high current density
|
Check pretreatment and improvement
Activated carbon treatment
Activated carbon treatment
Reduce current density
|
Slow deposition rate
|
Low zinc content
EDTA excess
Low current density
The temperature is too low
|
Increase zinc anode
A period of time not to supplement
Increase current density
Raise the temperature to 20℃
|
Anode passivation, zinc ion decline
|
1.The anode area is small and the current density is high
2.Low sodium hydroxide
|
Increase zinc anode
Analyze and supplement sodium hydroxide
|
The coating is rough and the edges and corners are easy to burn
|
Over current density
Deficiency of main additive
High zinc and low alkali, imbalance
|
Reduce current density
Supplement additive
Analysis and adjustment
|
Â
http://www.ayhlnewmaterial.com/