A masterbatch apparent quality inspection
(1) The appearance of the masterbatch should be free of continuous particles and dust, with a bright surface and uniform color
(2) The size of the masterbatch is uniform, usually we use 3mm diameter as the best particle size of the conventional masterbatch:
(3) The surface of the masterbatch should be smooth and flat. If the particles have more raised points, it is due to uneven plasticization or poor dispersion. If the particles are hollow or foamed, the water content in the masterbatch is higher, which is a vacuum in the production of the masterbatch. Caused by poor exhaust
Common problems in the use of B masterbatch
(1) Black spots
There are black spot particles on the surface or inside of the product, and the main reasons for the black spots are: the cleaning machine is not clean: there are black spots in the raw materials: the screw is carbonized; the environmental pollution.
Main solutions:
a. The machine was not cleaned up during the process of transferring to production. Clean the machine again.
b Strengthen incoming material inspection, especially black spots and impurities are more likely to appear in fillers or flame retardants
c. Note the control temperature and material processing time to prevent the processing temperature from being too high;
d. Pay attention to environmental hygiene. Do a good job of isolation and protection between machines of different colors
(2) Discoloration
The color of the product changes during the production process, and there is obvious color difference. The reasons are: uneven mixing; unclean cleaning; too high temperature: strong shear
Main solution
a. Strictly follow the mixing process to ensure the uniformity of the mixing;
b. Arrange inspection after the cleaning is completed to ensure that the cleaning is clean
c. Control the extrusion temperature to prevent the pigment from decomposing due to excessive temperature:
d. Choose a suitable screw combination to avoid too strong shear.
(3) Bubble
Air lines on the product surface, or vacuum eyes and foaming on the cut surface, are mainly due to: the vacuum system is blocked; the master batch is damp; the plastic has high water content
Main solutions:
a. Regularly inspect and maintain the vacuum system
b. Dry the raw materials with higher water content in advance
c. Reasonably control inventory to avoid prolonged storage of wet materials
(4) Poor plasticization
There are refractory substances on the surface of the product, or the surface is black and has toad skin. The main reasons are: the heating temperature is too low and the raw material compatibility is poor
Main solutions:
a. The processing temperature of root raw materials, set the best temperature for product processing;
b. Confirm the compatibility of the masterbatch with the plastic. If it is incompatible, select the special masterbatch for the plastic
(5) Carbonization
The leaking material at the die is coked and turned into black material, and granular scorch appears on the surface of the plastic. The main reasons for carbonization are that the heating temperature is too high, causing the melt to burn; the screw is used for a long time without cleaning, and the scorch accumulates: the downtime is too long, and the head and screw are not cleaned.
Main solution
a. Frequently check whether the heating system is normal, and if there is a problem with the heating system, solve it in time;
b. Regularly clean the screw or machine head and thoroughly clean it
c. The filter plate, filter screen and die should be cleaned in time and clean to prevent carbonization. If carbonization is found, the machine head and screw should be cleaned immediately.
PUDA masterbatch packing machine:
Ususlly we use free flow type machine to pack masterbatch, but it depends on material's bulk density, air content and water content. Also we offer open bag machine and valve bag machine and dual bag machine for customers to choose their best.
