Analysis of Static Friction Coefficient Between Work-piece and Rubber Belt in Sanding Wood-Based Panel

This study analyzes the critical static friction coefficient (μ0) and the static friction coefficient (μ) between work-piece and rubber belt during sanding medium density fiberboard (MDF) and particle board (PB). The purpose is to provide theoretical support for improving design techniques of sanding machine and choosing appropriate rubber belts for sanding. The results indicate that μ0 is a constant that can be calculated by maximum sanding force (sFMax) and maximum normal force (nFMax). Besides, there is an exponential relationship between intensity of pressure (P) and μ when work-piece is relatively static on a rubber belt. Among all sanding parameters, git size (G) has the greatest influence on μ. In single-factor experiment, we found that the smaller the nFMax is, the greater the μ is (for same rubber belts), but the variation rates of μ and nFMax are coincident. Six types of rubber belts are adopted, and the average μ of No. 1 and No. 4 are greater than others, but average μ of all the belts are lower than μ0, so when use such six types of rubber belts, a hold-down device or vacuum chuck should be equipped on the sanding machine. Patterns of rubber belts have some impact on μ, and appropriate patterns on the surface of rubber belts contribute to higher μ.