Study on vibration of the saw cylinder and its critical speed

Abstract

The force impact of the 130 saw cylinder of gins 4DP-130 and 5DP-130 was studied. It was determined that due to the significant weight of the saw cylinder, when it is rotated at 730 rpm, its radial runout increases, leading to shaft deflection and wear of its neck for bearing fit, rapid wear of the working part of the grates in the grate and blunting of saw teeth when saw teeth touching the grate, which led to their rapid wear. Increased wear of the saw blade and grate, increases the consumption of imported saws and grates, reducing their service life. In addition, due to the increase in the radial runout of the saw cylinder, it was impossible to set the necessary gaps of 1.5-2.0 mm along the entire length between the saw cylinder and the air chamber nozzle, which did not ensure complete removal of the fiber from the saw teeth and its transportation to the fiber discharge channel. This led to a decrease in the productivity of the gin and the daily production of fiber. When studying the saw cylinder, it was revealed that with a decrease in the mass of the shaft, the deflection and vibration of it should decrease, increasing stability. In this regard, a hollow shaft for saw gin is proposed. Theoretically, the critical speed of a hollow shaft for 130 saw gins is considered. It is determined that for the stability of the saw cylinder, its critical speed must be.