In the production process of blow molding barrels, color difference may occur.
Today, Yankang will share with you the solution of color difference in the production process of blow molding barrels.
Problems with blow molding machine parts
The blown screw of the blow molding machine has a damage gap for a long time, and there is a material dead angle at the notch. During the production process, the previous batch of different color raw materials slips, resulting in an uninterrupted color difference of the finished product.
Color difference solution: it is necessary to check the size of the damage problem, is the choice of repair or replacement screw.
Problems of raw materials and color masterbatch
Control of raw materials is the key to solve the color difference.
If the full use of new material to control the temperature parameters, the raw material caused by the basic possibility of finished product color difference is very small. If the back material is added, the color difference of the finished product will occur due to the color value of the back material and the uneven mixing in the process of adding quantity.
Color difference solution:
If the production added back to the material, according to the performance of the back to the material, to adjust the proportion of adding and mixing time, to ensure that the raw material is uniform, reduce the color difference of the finished product.
In the use of masterbatch, strengthen the inspection of raw materials into the warehouse.
Production of the same product as far as possible with the same manufacturer, the same brand of masterbatch, masterbatch production.
If you need to change the color master manufacturer, do a good sample test, in line with the standard, before the batch production.
Uneven mixing of raw materials and masterbatch
Poor mixing of raw materials with the masterbatch can also result in color changes.
After the mixing of raw materials and color masterbatch is uniform, the color masterbatch is separated from the masterbatch due to electrostatic effect and easily adsorbed on the hopper wall when the raw material and color masterbatch are fed into the hopper through the lower suction material. This is bound to cause the change of color masterbatch quantity in the blowing period and thus produce the color difference.
Color difference solution: the most effective way is not to use the suction machine, but the use of hot air dryer, with the method of artificial feeding to prevent the color powder and masterbatch separation caused by the color difference.
Cylinder temperature affects the color difference
In production, it is often encountered that a heating ring is damaged or the heating control part is out of control, and the temperature of the long firing material cylinder changes dramatically, resulting in color difference.
Generally, the failure of the heating ring to produce color difference will be accompanied by an uneven plasticizing phenomenon. But the heating control part loses control the long-burning often accompanies the product gas spot, the serious discoloration even the coking phenomenon.
Color difference solution: therefore, it is necessary to check the heating part frequently in production, and timely replace and repair the heating part if it is damaged or out of control, so as to reduce the probability of such color difference.
Problems in production process adjustment
When adjusting the blowing process parameters in the production process, as far as possible, the blowing temperature, back pressure, blowing cycle, and the amount of color masterbatch should not be changed. At the same time, the influence of the changing process parameters on the color and luster should be observed.
Above is about the solution of color difference in the process of blow molding barrel production.
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