Centrifugal fan output decline may exist for the following reasons: 1: motor stator winding fault as local short-circuit caused the speed dropped 2: impeller may have to pay dirt with the load increase the impact of its speed 3: impeller unbalance (at the same time there will be abnormal vibration) 4: Are there obstacles inlet air intake of substances such as inlet valve off small or dirty air inlet filter clogged other reasons. For the selection of the bearing using the unit will change in accordance with the general equipment manufacturers of the original model with a rather large selection of note is appropriate, bearing improper selection. With the bearing and the bearing bore is generally used JS7 / BU 6, so not too tight with limited impact on the bearing clearance for higher speeds, I make a high temperature centrifugal fan, due to bearing and shelters Tighten the coupling bolts tight general case do not use the torque wrench, in order to lock in Chengdu centrifugal fan size, tightening force is often too large, so that the one for the clearance smaller, thus causing the bearing heat caused by high temperatures;! or because the bearing Jilin clearance small aluminum centrifugal fans, leading to self-mountain-side bearings can not automatically move with the axis thermal expansion, so that both the bearing axial load is too large centrifugal fans, causing heat damage bearings. Therefore, the production of replacement bearings, especially high temperature high speed centrifugal fan bearings, pay attention to the selection of bearings: ① attention to the speed limit is appropriate, ③ to choose the original clearance larger group C3 bearings. Chengdu size centrifugal fans, centrifugal fans, blowers nagorye provided by Shanxi nagorye blower limited liability company. Shanxi nagorye Blower Co., Ltd. (www.sxgfj.cn) strong, credible, Shanxi Xinzhou fan, ventilation equipment industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead nagorye blower and you hand into the brilliant, for a better future!