Cement mill main reducer high speed shaft dynamic fault and its treatment

Cement mill main reducer high speed shaft running 2020 - dynamic fault and its treatment 04 - 08 chang-hai li ( Huai hai China united cement group co. , LTD. ) A profile, high speed shaft and its axial channeling dynamic fault 2 # cement mill for 4 a company. 2 m× 13. 2 m, Taiwan production in 105 ~ 135 t/h, the original is equipped with two sets of Romania production HB180 main reducer ( The power of 2000 kw) Transmission, with double edges. The load of the equipment are high, also has a high availability requirements. In September 2001 was provided, to replace two HB180 main reducer with two ZLY1045 domestic reducer ( ZLY1045 reducer gear structure and technical parameters are shown in table 1) 。 ZLY1045 domestic reducer power of 2000 kw, the input speed of 985 r/min, ratio of 9. 022; The reducer high speed shaft has three supporting bearing, for freedom bearing ( 23140 cc / W33) , the middle for locating bearing ( 23148 cc / W33) , as shown in figure 1. Table 1 ZLY1045 structure and technical parameters of gear reducer is shown in figure 1 gearbox gear component structure diagram on August 12, 2006, in the inspection found that the reducer high speed shaft bearing axial vibration increase than before, the maximum vibration speed 12 mm/s. Open the reducer after inspection found, of which the positioning bearing housings about 1/2 transverse cracking, cause bearing axial positioning failure, this is the main cause of bearing axial vibration. The lower bearing seat and the reducer casing is integrally cast, the scene could not repair, such as demolition back to factory processing, need 30 d, cycle is too long. Then organize relevant personnel, the company decided to transmit the auxiliary end bearing ( Originally free bearing) To manipulate the positioning. Second, channeling dynamic analysis of the causes from the damage of bearing seat section, the bearing some casting defects such as porosity, slag inclusion, cause the loss of strength. In addition, because of the speed reducer for transmission helical, primary tooth spiral Angle for 13 & deg; , look from the primary side, high-speed shaft clockwise operation, running speed reducer gear mesh make bearing axial force, and stress direction pointing to secondary side, as shown in figure 2. Figure 2 clockwise operation reducer gear mesh to make the bearing axial force three, treatment measures and effects ( 1) Because of middle positioning bearing housings can't repair, so decided to locate auxiliary preach end bearing. Particular way is: measurement in auxiliary bearing outer gland and bearing processing after the distance between a positioning ring, detailed dimension for & Phi; 370× Φ 350× H30, and made two and a half, do not need to tear open the wheel can be installed; The junction between the end cover and the box body and adjusting pad adjustment, to keep gland between seam allowance and block set of 0. 2 to 0. 3 mm gap and avoid bearing heat expansion, cause bearing heating, as shown in figure 3. Figure 3 transformation ( 2) Due to bearing end cover mouth height only 5 mm, and check the thickness of the flange only 14 mm, in order to ensure the reliable bearing positioning, bearing end cover for the transformation process, check the mouth height increased from 5 mm to 20 mm, check flange thickness increased from the original 14 mm to 30 mm, and the design into two fission, without auxiliary pass down the side of wheel can be installed. In addition, for reducer internal cleaning and replacement of new oil. Through the improved processing, with only 28 h on the trial production, the axial gained speed of 2. 6mm/s。 So far have been used in more than two years of maintenance, operating normally, to create a large number of economic benefits for enterprises.