Reducing fan blade vibration in rice harvesters and combine harvesters by applying product grouping

Abstract

Currently, several thousand of rice harvesters and combine harvesters are assembled every year. These harvesters are sold within Thailand and exported to the CLMV and South Asian countries. However, one of the major claims of these products is broken bolts at the connection between fan blade and fan shaft. The investigation indicated that a cause of this failure is high vibration of a fan unit. In order to eliminate this failure, vibration control of the fan unit is required. However, a production line is a lot of time consumption for balancing a fan unit of these harvesters because operators must do both static and dynamic balancing processes for every single fan unit. According to the primary investigation, the variation in position and dimension of the fan blade is a major cause of its unbalance. In order to reduce this variation, a new standard procedure was introduced. This procedure was developed based on an assumption that the vibration of the fan unit can be significantly decreased if the standard deviation of the fan blade’s weight is reduced. Experimental results indicated that the new procedure can reduce time consumption for doing static and dynamic balancing processes of the fan unit significantly. For example, in case of a 4-ft fan unit, the total assembly time of the fan unit can be reduced for more than 50%. Currently, this new procedure has been used in several production lines. © Research India Publications.