Study On The Influence Of Hammer Pieces' Abrasion On Hammer Mill's Rotor Vibration

The imbalance of the rotor is one of the familiar running malfunctions for the muller. In the course of milling, thanks to the arranging form of the hammer pieces and other factors, the hammer pieces are usually fretted asymmetrically, that will bring on eccentricity to the rotor's mass and the rotor will lose its balance. Inspirited periodically by means of centrifugal inertial force, the lopsided rotor will produce coercionary vibration and inordinate noises, accordingly result in the exacerbating of the working conditions. At the same time, the components of the axletree will wear down quickly, that has reduced the natural life and working efficiency. Therefore it's significant to make scientific researches on the influence, which the rotor's balance will come in for when the hammer pieces were abrased.The whole research can be divided into two parts, namely, the academic research and the vibration measurement. The academic research has served as the base of the vibration measurement. Via the analysis and research on the vibration mechanism of the rotor, the researcher has established the mechanical model and differential equation for the rotor's vibration; thus, the influencing relation between the hammer pieces' abrasion and the rotor's vibration has been established in theory.The vibration testing is aimed at validating and consummating the outcome of the theoretical analysis. In this research, the flowing things have been done: (1) adopting the programming software named Lab VIWEW by the mode of graphics, a virtual vibration test system has been developed, by which we can realize the real-time acquisition, analysis and data processing of the vibration signals; (2) by means of measuring the swing of the vibration system, we can form the relation curve reflecting the correlation between the vibration intensity and the imbalance grade, and it's expression is ; (3) via testing the system's frequency of vibration, we can acquire the expression of the steady-going response for the system; (4) basing on testing the system's frequency of synchronous vibration, and substituting it for the system's inherent frequency, we can obtain the system's two main vibratory parameters, namely, the system's rigidity and damp with the sameeffect, so that we can consummate the mechanical model in the part of theoretic analysis.Combining the theoretic research and the result of the vibration testing, we can make sure that the hammer pieces' abrasion has prominent effect on the vibration of the rotor. When the hammer pieces have been abraded asymmetrically, with the increasing of the imbalance degree of the rotor, the intensity of the rotor's vibration will also continually tone up. In addition to these, when the system's dynamic parameters with characteristics are invariable, the intensity of the rotor (swing A) is in direct proportion to it's imbalance degree (E). It's one of the innovative features for the research to convert the traditional qualitative study into digital analysis and express the correlation between the rotor's vibration intensity and its imbalance degree. The relation curve and vibration parameters obtained by testing will provide important foundations for the optimization of rotor designing, the overhaul and replacing of the hammer pieces, the verifying of the muller's dynamic balancing and the vibration surveillance of the rotor.