The shaker screen noise is generally higher than 90dB (A)when it is in the normal screening operations, this exceeds health standards of environmental noise 85dB (A) and industry standard ZBD95001 --- 87 provisions 90dB (A). This has seriously affected the workers’health, so attracted people’s attention. The Research results are: paste damping on the sides, paint damping or use constrained damping layer; replace the side panel with a metal frame; use rubber sieve bottom, polyurethane sieve bottom or plastic bag strip; provide damper or balance mass on the eccentric shaft; set rubber or polyurethane cushion between the bearing and the bearing outer ring; replace the metal gears with a flexible pieces of plate gear.
It is noteworthy that bearing is the main source of vibration noise source that the derrick screen is difficult to control. Since shaker rely a great incentive force to keep the work, so bearings to withstand large radial force. If the lubrication is poor, it will have a greater friction, makes the bearing temperature too high, the thermal expansion is too large, so the radial clearance will significantly reduce. Which in turn exacerbated the wear rise to further improve. To this end shaker now generally use a large bearing clearance, such as 3G3624 bearings. However, due to the larger radial clearance, it reduce the natural frequency of the radial bearing system. But also increases the possibility of rolling runout after be disturbed and its impact ferrule power. Thereby increasing the vibration of the high frequency portion, produce a strong high-frequency noise. Theoretical and experimental analysis shows that: the use of hollow bearing has better noise reduction.
Scientific and effective screening method that can improve the efficiency of derrick screen and production capacity. There are two main aspects research work in this area. 1. The theoretical model of material move on the screen surface. Establish an accurate and practical material screening theory. It is essential for rational choosing shaker dynamics and kinematics. More representative of the screen surface material movement theories are: single-particle material beating on the derrick screen surface model theory; material group on the shake screen surface Collision model theory; material group vibration theory and cell layer theory. 2. Movement analysis of the material in the screen surface. There are two motion analysis methods of material in the screen surface. One is base on a single particle bounce theory, obtain kinematic parameters of the theoretical average speed of the material, then in accordance with the experimental results to introduce into the materials group interaction coefficient to be amended. The other is the use of collision theory, put forward materials group kinematic parameters. In order to prevent material clogging the sieve opening, people have made unremitting study.