Common problems in the manufacturing of resin bonded grinding wheels
Resin abrasives is an important part of abrasives and one of the important common and important grinding tools in industrial production. In order to promote technical exchanges in the industry and help customers to solve common problems in the manufacturing process of resin grinding wheels, this article mainly introduces common problems in the manufacturing of resin bonded grinding wheels.
I. Analysis of the causes of unstable quality of resin grinding wheel
There are many quality problems in the production process of resin grinding wheels.
Raw material problem
The Resin Abrasive Wheels are complex product made from a variety of main and auxiliary raw materials including filler, reinforcing material, coloring agent etc.
1. about abrasives At present, the quality of abrasives on the market is uneven, mainly as follows:
(1). The chemical specification of abrasives is often qualified, but also with poor physical properties. It is mainly shown that there is still a gap between bulk density of China and international quality material. (2). The particle distribution of some abrasives is disordered, which is quite different from the standard specification.
2. In terms of binder, mainly about phenolic resin:
(1). Resin quality stability problems, especially the level of free phenol in the resin. Excessive free phenol content will accelerate the cracking of the Resin Cutting Disc after heating and hardening of the resin wheel and affect the strength of the grinding wheel;
(2). The binder’s particle is too thick or too fine: It is generally believed that the fine grain is benefitial to uniform distribution of the binder. If the grain is too coarse, the molding material is not easily mixed uniformly, which affects the hardness and strength of the grinding wheel. Even for the coarse-grained resin sheet cutting wheel and the cymbal grinding wheel, the size of the binder (resin powder) selected should be finer than 320#.
Manufacturing process of resin grinding wheel
The manufacturing of Resin Grinding Disc is a highly technical industrial process. There are many problems in the processes of materials mixing, molding, hardening, and processing.
(1). Mixing process: The key of mixing is uniformity.
(2). Molding process: At present, rotating material distribution mechanism is widely applied in domestic market. But due to the limitations of the rotating material distribution mechanism, the employees of some large manufacturing enterprises have no way to operate, which causes the distribution of mixed materials uneven.
(3). Hardening process: This is the most critical production process. There are two factors that easily cause quality problems. One is the temperature difference among the curing oven or the firing kiln is too large. The other is improperly installed furnace.
(4). Manufacture procedure (mainly large-diameter and high-thickness resin grinding wheels): Resin grinding wheels, especially with large diameters and high thicknesses, or with strict dimensional tolerance must be processed after hardening to ensure the geometric size and tolerance.
(5). Apply the production formula and process parameters mechanically.