CKP240 cement vertical mill common failure analysis and solution measures

CKP240 cement vertical mill 2020 - common failure analysis and solution measures 10 - 17 BuJiangJiang YueHongMei ( Jidong cement ( Yantai) Co. , LTD. ) Vertical mill complex structure, high maintenance requirements, difficult operation, production is restricted by the problem of stable operation. Based on the vertical mill in the production process of roller shell burst, gland bolts fracture problem, put forward technical transformation measures, eliminates the hidden trouble, reduce maintenance costs, improve equipment reliability. 01 gland bolts fracture 1. Phenomenon 1 file now mill roller bearing ring bolt cut off, the original performance for roller lubrication oil station drops rapidly, if found, not in time grinding roll assembly soon went forward, leading to intermittent contact with mill rollers, occasionally send file 'dong, dong' banging, after further deterioration will also cause bearing lock, characterized by vertical mill current drops rapidly, about 20 a lower than normal. 1. 2 the reason analysis of roller structure as shown in figure 1, the labyrinth seal and gland surrounding clearance design value is 0. 6 mm, each gland bolts when cut off, after opening will be found between the labyrinth seal and gland with traces of friction, even though their gland bolts are not cut off all have friction marks, thus can judge the labyrinth clearance design here is too small, the main reason is that the design has failed to fully consider grinding temperature change caused by thermal expansion because different materials and different conditions. Grinding temperature can reach 118 ℃ in summer, even if the winter will reach more than 95 ℃, due to the labyrinth seal two kinds of material thermal expansion coefficient of different causing bulging die maze, roller rotation is not flexible. In addition, by measuring the axial clearance of the roller, found some roller up to 1 mm, and the theoretical value should be zero. 15 - 0. 25mm。 Axial clearance is too large, lead to in the process of running up before and after the grinding roller is too large, further exacerbating the sealing ring bolt because of the force is too large, the phenomenon of the fracture, because of the thrust bearing for fission bearing, once appear, gland bolts cutting, grinding roll up will be. 1. Three solutions to processing of gland, to 1 mm on each side, make the labyrinth clearance reaches 1. 6 mm, at the same time, the roller seal fan instead of air volume and total pressure greater seal fan, make up for the labyrinth gap bigger after air volume loss, to ensure that the seal fan pressure is still greater than 3000 pa; For grinding roller to the clearance is too large, first of all, in the case of no pressure seal will tighten gland bolts, measure the bearing clearance value, then the interval set processing, use grinding machine to grind the thickness of thin, size depends on the axial clearance of the deviation value, but there is no certain proportion relationship, the two best points and a small amount of processing for many times, until clearance control in the reasonable scope, this time with a lead wire out gasket thickness, pressure on thickness as a benchmark to choose the appropriate seal axial clearance can be adjusted. 2 02 roller set up scamper to crack. 1 phenomenon in the process of running hear grinding is the sound of 'dong, dong', open the door check found that is grinding roller cracking, a different tone is mainly caused by the roller opened up move forward after collision with mill, sometimes in the repair process will also hear the sound of the 'KaBa, inspection found to be the grinding crack. 2. 2 reason analysis of the grinding crack section is relatively neatly, sometimes burst for running, sometimes to crack during downtime, so can judge and foreign body into the relationship is not big. Via detecting ground gas temperature as high as 110 ℃, material temperature about 130 ℃, the basically high temperature is the direct cause of the grinding crack. In addition, the grinding small curvature radius ( As shown in figure 2) As well as the material of high hardness, brittleness, further promoted the grinding crack. 2. 3 solutions to improve clinker grate cooler is ventilated, reduce the temperature of the clinker, roller roller set material welding by high sawing cast iron instead, in the belt grinding increase iron remover and metal detectors, reducing or eliminating foreign bodies to enter. Since the above measures, in addition to the regular surfacing annually roller set, never seen roller shell cracking phenomenon, and welding roller set of abrasion resistance is far better than that of high chromium cast iron roller set, not only greatly improve the reliability of the equipment, but also reduce the maintenance cost. Due to obvious energy saving effect, vertical mill system existing in grinding process is the device of choice, but its structure is relatively complex, higher requirements for maintenance, a thorough understanding of equipment operation, the root cause analysis for concrete problems to solve and improve measures, to guarantee the performance of the roller mill. Source: 'cement' 11, 2019