Key Questions to Ask When Ordering Coil Coating Line

The first step is to ensure a perfect wetting of the aluminum particles. If all aluminum particles are separated from each other and wetted properly the best metallic effects are achieved. DISPERBYK-163/ DISPERBYK- should be added while dispersing the aluminum particles. The aminic pigment affinic groups show a strong affinity to the aluminum particles. It is advised to start with a dosage of 1.5% solid wetting & dispersing additive on aluminum pigment. Depending on the particle size of the aluminum pigment the required dosage can vary. Thus, a dosage ladder should be tested.

For more information, please visit Litong.

The next step is to ensure the storage stability of the aluminum paste. For this it is advised to add RHEOBYK-D 410 after dispersing the aluminum pigment. RHEOBYK-D 410 is a rheology modifier which prevent the aluminum particles from settling.

In our portfolio there are several wetting & dispersing additives which are especially suitable for coil coating application.

These wetting & dispersing additives can be used to disperse and stabilize all kind of pigments.

It is recommended to prepare white mixtures (e.g. white with carbon black, with iron oxide red, with phthalo blue etc.)

The color stability should be tested performing a rub out test. Additionally the high speed stirring stability should be tested.

These white mixtures need to be applied, rub out and high speed stirring stability should be tested, too.

For more Coil Coating Lineinformation, please contact us. We will provide professional answers.

Of every sample the storage stability should be tested. This can be done by storing the samples in the oven for at least three days at 50°C.

After storage the samples should be applied again the same way as done before storage.

A well dispersed and stabilized samples should have a delta E below 0.5 and a good leveling. After storage gloss and color stability should be the same as before storage.

We recommend testing DISPERBYK-110, DISPERBYK-180 for titanium dioxide and inorganic pigments. DISPERBYK-170, DISPERBYK- and DISPERBYK- can be used for all kind of pigments including carbon black.

In the best case all pigments can be stabilized using only one additive. But often a combination of two wetting & dispersing additives is required. For example DISPERBYK-110 could be used for titanium dioxide and inorganic pigments and DISPERBYK- could be used for organic pigments.

In this case our wetting and dispersing additives called DISPERBYK should be used. We recommend preparing single pigment pastes. First thing to check is the mill base viscosity. While using a proper wetting and dispersing additive the viscosity should be lowered significantly. A low(er) mill base viscosity already indicates a good wetting and dispersing of the pigment. Next we recommend preparing white mixtures using the pastes, e.g. white with carbon black, with iron oxide red, with phthalo blue etc. These white mixtures need to be applied, rub out and high speed stirring stability should be tested, too. The mixtures should be stored in hot box for at least 3 days at 50°C. After storage in hot box the application will be repeated the same way as before. A good mixture shows high gloss, good levelling and low delta E values (< 0.5) before and after storage and also during storage there may not be a big change in colour and gloss. We recommend testing DISPERBYK-110, DISPERBYK-180 for Titanium dioxide and inorganic pigments. DISPERBYK-170, DISPERBYK-171, DISPERBYK-174 and DISPERBYK- can be used for all kind of pigments including carbon black. It is difficult to find a solution based on one single wetting and dispersing additive. A typical solution could be DISPERBYK-110 used on Titanium dioxide and DISPERBYK- on all other pigments. For starting point formulations and starting point dosages please contact us. The dosages (depending on the type of pigment) can strongly vary.

If you are looking for more details, kindly visit Double coating line.

related articles Weifang HiTo Equipment Engineering Co.,Ltd will be highly responsible to requirements of every customer. Contact!










HiTo Eq. Eng. manufacturing of double-coated, double-baked CCL, pre-painted steel sheets with good weather resistance, primarily used in construction and home appliances, is possible.

Supply three-coating, three baking color coating line too, multi-color painter with color coating line for pattern PPGI/PPGL, And in-line tension leveler can also be installed to manufacture straightened steel sheets.
 Carbon Steel Coils Continuous Annealing Hot-dip Galvanizing Line, Galvalume Line
 The formation process of the hot-dip galvanized layer is the process of forming an iron-zinc alloy between the iron matrix and the outermost pure zinc layer. The iron-zinc alloy layer is formed on the surface of the workpiece during hot-dip coating, which makes the iron and pure zinc layer very close. Good combination, the process can be simply described as: when the iron workpiece is immersed in molten zinc, a solid solution of zinc and α iron (body core) is first formed on the interface. This is a crystal formed by dissolving zinc atoms in the base metal iron in a solid state. 
 The two metal atoms are fused, and the attraction between the atoms is relatively small. Therefore, when zinc reaches saturation in the solid solution, the two element atoms of zinc and iron diffuse each other, and the zinc atoms that have diffused (or infiltrated) into the iron matrix migrate in the matrix lattice, and gradually form alloys with iron and diffuse The iron and zinc in the molten zinc form an intermetallic compound FeZn13, which sinks into the bottom of the hot-dip galvanizing pot, which is called zinc dross. When the workpiece is removed from the zinc immersion solution, a pure zinc layer is formed on the surface, which is a hexagonal crystal. Its iron content is not more than 0.003%.
 Hot-dip galvanized layer protection performance
 The thickness of the electro-galvanized layer is usually 5-15μm, and the hot-dip galvanized layer is generally above 65μm, even as high as 100μm. Hot-dip galvanizing has good coverage, dense coating and no organic inclusions. As we all know, the mechanism of zinc resistance to atmospheric corrosion includes mechanical protection and electrochemical protection. Under atmospheric corrosion conditions, there are protective films of ZnO, Zn(OH)2 and basic zinc carbonate on the surface of the zinc layer, which can slow down the corrosion of zinc to a certain extent. 
 The layer protective film (also called white rust) is damaged and a new layer is formed. When the zinc layer is seriously damaged and the iron matrix is endangered, zinc will produce electrochemical protection to the matrix. The standard potential of zinc is -0.76V, and the standard potential of iron is -0.44V. When zinc and iron form a microbattery, zinc is dissolved as an anode. Protected as a cathode. Obviously, hot-dip galvanizing has better atmospheric corrosion resistance to base metal iron than electro-galvanizing.
 Formation control of zinc ash and slag during hot-dip galvanizing
 Zinc ash and zinc slag not only seriously affect the quality of the zinc dipping layer, but also cause the coating to be rough and produce zinc nodules. Moreover, the cost of hot-dip galvanizing is greatly increased. Usually, the zinc consumption is 80-120kg per 1t workpiece. If the zinc ash and dross are serious, the zinc consumption will be as high as 140-200kg.  
 Controlling the zinc carbon is mainly to control the temperature and reduce the scum produced by the oxidation of the zinc liquid surface. Some domestic manufacturers use refractory sand, charcoal ash, etc. Foreign countries use ceramic or glass balls that have low thermal conductivity, high melting point, low specific gravity, and do not react with zinc liquid, which can reduce heat loss and prevent oxidation. This kind of ball is easy to be pushed away by the workpiece and has no adhesion to the workpiece. Side effect.
For the formation of zinc dross in zinc liquid, it is mainly a zinc-iron alloy with extremely poor fluidity formed when the iron content dissolved in the zinc liquid exceeds the solubility at this temperature. The zinc content in the zinc dross can be as high as 95%, which is hot-dip galvanizing. The key to the high cost of zinc.
 From the solubility curve of iron in zinc liquid, it can be seen that the amount of dissolved iron, that is, the amount of iron loss, is different at different temperatures and different holding times. At around 500℃, the iron loss increases sharply with heating and holding time, almost in a linear relationship. 
 Below or above the range of 480～510℃, the iron loss increases slowly with time. Therefore, people call 480～510℃ the malignant dissolution zone. In this temperature range, the zinc solution will corrode the workpiece and the zinc pot the most severely. The iron loss will increase significantly when the temperature is above 560℃. If the temperature is above 660℃, the zinc will destructively etch the iron matrix. The zinc dross will increase sharply and the plating will not be possible. . Therefore, plating is currently carried out in the two regions of 450-480°C and 520-560°C.


Weifang HiTo Equipment Engineering Co.,Ltd has got three orders in , UAE coils continuous hot dip galvanizing line, Iran coils continuous color coating line, Bangladesh steel coils colour coating line.

My factory all workers hurry up to manufacture all equipment, ensure timely delivery according to the contract.


HiTo Equipment Engineering Company has supplied two color coating production line to Bangladesh market, and each one capacity is more than the single machine production capacity of the current operating production line, The huge demand market in Bangladesh is the biggest driving force behind the improvement of production lines, and more and more factories are considering updating new production lines.



The modern color coating production line has added a printing equipment process section, which can produce beautiful patterns and colors, such as flowers, wood grain, traditional patterns, stacked stone patterns, etc. However, the investment on equipment is also enormous.











HiTo has completed the shipment of equipment to the customer in Bangladesh in February . And HiTo installation term will go to Bangladesh to start installation work, We will start the debugging work of the entire production line in three months and help the customer start production as soon as possible to achieve the fastest profit After three months of procurement, production and five months of installation, the project in Dubai enters the debugging stage.The customer purchased a color coating line from HiTo,it works well.After one year,he ordered a hot dip galvanizing line.Thanks customer's trust to Weifang HiTo Equipment Engineering Co.,ltd.

HiTo Engineering has been manufacturing Coils Coating Lines such as Coils Continuous Hot Dip Galvanizing Line(Carbon Steel Coils Galvalume Line) and Coil Color Coating Line (Coils Paint Coating Line) since and has over 80 references worldwide.

The HiTo Continuous Galvalume Line has various design features and can produce high-quality products suitable for the following markets:


Roof and wall coverings
Drainage ditch
Fences and walls
Building products: Sandwich Panel no data