Formula and production process of diamond wet polishing pad and dry polishing pad

With the increasing development of the country's economy, the awareness of resource conservation and environmental protection has gradually strengthened. In terms of stone surface polishing, we are working on developing a product capable of dry grinding & polishing to solve the problems of energy saving, environmental protection and user safety. In foreign countries, new diamond dry polishing pads have gradually replaced the use of some diamond wet polishing pads. Some large stone processing bases in China, such as Guangdong Yunfu, Foshan, Fujian Quanzhou, Xiamen, Shandong Laizhou, etc., have begun to use dry polishing pads. With the continuous update and improvement of diamond dry polishing pad products in the process of use, it has become a trend to completely replace the use of wet polishing pad.

Dry abrasive production method

After the resin material and glue are stirred, they exist in the form of liquid during the production operation, unlike wet polishing pad powder, which is easy to fly. Pour the mixed powder into the forming mold, unload the mold with a special clamp, and bake in an oven for 20 minutes at a temperature of about 70°C to solidify and form.
Since the dry polishing pad was first developed and applied abroad, it has just started in China. The use of some raw materials and the characteristics of the curing agent are not well understood. Some processing methods are limited. Now the domestic production of dry polishing pads is mainly based on Manual operation is the main method, and batch production cannot be carried out in a short period of time, thereby directly affecting the production efficiency of the dry polishing pad and increasing the production cost of the dry polishing pad.

 

Wet polishing pad production method

 

The main raw materials for making wet polishing pads in China are melamine resin and phenolic resin, plus other auxiliary materials, such as: rosin modified resin, calcium sulfate dihydrate, etc., and the forming heating equipment is a flat vulcanizing machine. The prepared powder is poured into the mold, the heating temperature is below 200°C, and the heating time is controlled between 9 and 10 minutes. The raw materials of wet polishing pads have certain toxicity, such as: melamine resin powder, phenolic resin, etc. are toxic substances. Long-term exposure of workers and inadequate protection measures are likely to cause harm to health.

 

The appearance comparison between the dry grinding plate and the water grinding plate is shown in Figure 1 and Figure 2

The dry polishing pad is mixed and stirred with glue, baked and cured in an oven, with high bonding strength and smooth surface; the wet polishing pad is formed by a press mold at one time, and if the material is unevenly spread, it is easy to cause particle loss (dropping teeth).

 

1 Selection of Diamond Raw Materials for Diamond Resin Dry Polishing Pads

Resin and vitrified bond diamond abrasive tools are suitable for RVD varieties. Optional diamonds that belong to fine grinding and grinding in terms of particle size

Granularity number: 50/60, 60/70, 70/80, 80/100, 100/120, 120/140, 140/170, 170/230, 230/270, 270/325, 325/400, 400/ 500.
Optional micropowder grade superabrasives belonging to the polishing category: W40, W28, W20, W14, W10, W7, W5, W3.5, W2.5, W1.5, W1.0, W0.5.
According to the user's requirements for processing stone, the diamond particle size number is mainly divided into: 30#, 50#, 100#, 150#, 300#, 400#, 600#, 800#, 1000#, 1500#, 2000#, 3000#, BUFF white, BUFF black, etc.

 

2 Selection of raw materials for resin powder and auxiliary abrasives in the production of diamond resin dry polishing pads

Resin powder plays the role of glazing and coloring. The main varieties of colorants are Cr₂O₃ and Fe₂O₃, which are basically the same as those of ordinary ceramic abrasive tools. Cr₂O₃ and Fe₂O₃ are what we often call chrome green (see Figure 3) and iron green (see Figure 4), together with other zinc oxide and tin dioxide. Abrasives are the components that play a grinding role in abrasive tools [3]. Adding auxiliary abrasives such as silicon carbide and white corundum will have a better heat conduction effect, which can further improve the grinding efficiency of the grinding disc, and will not cause scratches on the stone surface. mark.

3 AB glue for mixing raw materials of diamond resin dry polishing pad

AB glue for diamond resin dry polishing pad plays a great role in the production process. It can not only resist high temperature during the grinding process, but also play a role in molding during the abrasive casting process. It can also make the product in production Curing in time after putting into the oven. Its main component A glue is epoxy resin glue (Figure 5a), and B glue is polyamide curing agent (Figure 5b).

Manufacturing process of diamond resin dry polishing pads

Batching→mixing→rubber mixing→preparing molds and fixtures→filling→unloading→shaping→baking in an oven→subsequent processing→finished products (as shown in Figure 6)