Common Problems in Resin Grinding Wheel Manufacturing

Grinding with abrasive tools is a very important type of mechanical processing method, and it is the most basic and preferred processing method for precision machining and ultra precision machining. It has been widely used in industry. Resin grinding tools are an important component of abrasive grinding tools and one of the important grinding tools for industrial production applications. This article mainly introduces common problems in the manufacturing of resin grinding wheels.

1、 Analysis of the reasons for unstable quality of resin grinding wheels

There will be many quality problems in the production process of resin grinding wheels, and due to the multidisciplinary nature of resin grinding wheel manufacturing, the causes are complex and varied.

Raw material issues

Resin grinding wheel is a complex system composed of various main and auxiliary raw materials. As long as the materials are abrasives and binders, the auxiliary materials include fillers, reinforcing materials, coloring agents, etc.

1. Issues that should be paid attention to in terms of abrasives

At present, the quality of abrasives on the market varies greatly, mainly manifested as:

（1）. The chemical composition of abrasives is often qualified, but their physical properties are poor; The main manifestation is that there is still a gap in the packing density of abrasives compared to foreign countries.

（2）. The particle size composition of abrasives is chaotic and deviates significantly from the standard specifications; This is mainly manifested in the difference in the basic particle content of abrasives with the same particle size compared to foreign countries.

2. In terms of binders, the main ones are phenolic resins:

（1）. The stability of resin quality, especially the level of free phenol content in the resin. Excessive free phenol content can accelerate the resin cracking of resin grinding wheels after heating and hardening, affecting the strength of the grinding wheels;

（2）. Uniformity of mixing resin powder with Urotropin. Urotropin, as a hardener for resin, is not added in sufficient amounts, resulting in incomplete resin hardening and affecting the strength and hardness of the grinding wheel; If the content is too high, the excess Urotropin will not bind with the resin and will decompose and evaporate during the hardening process, increasing the porosity of the grinding wheel and reducing its strength and hardness.

（3）. The binder particles are too coarse or too fine:

It is generally believed that the particle size of the binder should be fine, which is beneficial for making the binder evenly distributed. If the particle size is too coarse, the formed material is not easily mixed evenly, which affects the hardness and strength of the grinding wheel. Even for resin thin film cutting grinding wheels and cymbal shaped grinding wheels with coarse particle size, the selected binder (resin powder) particle size should be finer than 320 #.

However, if the particle size of phenolic resin powder is too fine, it brings difficulties to the mixture, making it difficult to achieve uniformity of the mixture, which in turn affects the cutting and grinding performance of the resin grinding wheel.