Common to reconditioned and hammer mill initial installation of the fuselage, where a strong vibration test run. This occurs mainly in the following reasons

(1) Maintenance hammer assembly installation errors. Hammer Plane turn used to prevent the rotor weight loss of balance, the hammer mill all together for face must turn around, otherwise strong vibrations occur during operation.
(2) corresponds to the difference between the two groups hammer weight over 5 grams. Exclusion method is to adjust the weight of the hammer, High-Pressure Suspension Grinder so that the weight of the two groups corresponding to the difference of less than 5 grams.
(3) Individual hammer card too tight, do not throw off running. Can be turned by hand after stopping to observe, think of ways to make the hammer rotation flexibility.
(4) Other parts by weight of the rotor imbalance,Winnowing pulverizer Mill then the need to adjust the balance were carefully examined.
(5) the shaft bending deformation. The solution is straightened or replaced.
(6) exceeds the limit or damaged bearing clearance. Replace with new bearings are generally used to solve the problem.