Vertical Mill pressure difference
Vertical Mill pressure difference is reflecting the Sintered Bauxite Raymond Mill load is one of the important parameters of internal material cycle. Mill pressure difference is mainly composed of two parts, one is vertical mill wind ring local ventilation resistance; The other part are produced by the classifier selection powder resistance, the sum of the two resistance constitutes the mill pressure difference. Under normal working condition of grinding in differential pressure should be stable, that is in a range in stabilizing change state, this marks the amount of raw materials into the vertical mill and the finished product quantity to achieve a dynamic balance, once the balance broken, grinding inner loop load changes, the pressure difference will jump or sharp reduction, if not promptly Cui Xiaoyu: such as heavy vertical mill grinding process of calcium carbonate and its operating effect control is analysed, that will affect the stable operation of the mill. Impact mill pressure difference of many factors, such as material grinding, feed feed rate and system air volume, the grinding pressure, rotating speed of classifier, etc. All the factors affecting grinding machine running steadily, almost can be reflected on the pressure difference.
Higher differential pressure show that the amount of raw materials is greater than the amount of Talc Powder Machinery Production products, grinding inner loop load increase, the feed improve mechanical and rheological, slag discharge quantity increase, at this time can be judged from mill limit device material layer is thickened. Fineness of qualified products, general separator speed do not adjusted (or in case will not affect the fineness can be appropriately reduced speed). Usual practice is to be cut, transient cutting processing, smooth mill differential pressure recovery, steady increase feed to reasonable value; Or in the range of allowable grinding machine Lord motor load does not do subtraction, cutting processing, appropriate to improve the roller pressure, increase the grinding ability, avoided mill grinding “full” situation, because of the heavy load vibration is produced. Differential pressure decrease is showed that the amount into the grinding material is less than the amount of finished product, circulate in mill load is reduced, the feeding enhance mechanical and electrical flow decreases, and reduced the volume of sludge discharge, at that moment, from mill spacing device can determine material bed is gradually thinning. Can take charging at this time, relief or reduce the ventilation measures, avoid mill grinding “empty” case, the vibration due to material layer is too thin. According to the debugging experience, under the same conditions, product fineness of the thinner, the mill and the higher pressure difference, and to be low. The practice of neutral ground operation parameters are interrelated, operation should pay attention to coordination of dynamic parameters.
The System Ventilation Rate
Graphite Mineral Milling Machine system the chase air volume, according to the theoretical calculation by the mill capacity generally consider duct air leakage resistance, system factors such as proper surplus (5% ~ 10%), can be concluded that roller mill system the chase the reasonable air volume and air pressure, it is also the fan selection basis. Vertical mill operation under negative pressure, the material conveying, drying, classification must be a lot of wind and proper ventilation rate is within the grinding machine is a necessary condition for stable operation. Grinding during the ventilation rate is directly affect the product yield and fineness. Ventilation rate, increase in wind speed, drying and conveying material, reduced the volume of internal and external circular grinding machine, bed coarse particles increased, material layer is thinner, mill output, if the volume is too big, can lead to unqualified product fineness (run) or product fine powder content (fewer cycle, short grinding time), quality to drop, mill also can produce vibration due to the material layer is too thin and; Wind speed reduced in the ventilation rate is small, grinding, drying and pick-up the ability is abate, increase quantity of internal and external circular grinding machine, thick material, grinding machine grinding increases power consumption, product fineness is fine, but mill production is reduced, at the same time, mill also on material layer is too thick load is too large and may cause vibration or vibration.
Vertical mill system ventilation rate is mainly through the fan damper opening (or fan motor frequency control of motor speed) to regulate, vertical grinding ontology, dust collector and air leakage had a great influence on grinding inside ventilation ventilation pipe, often cause the loss of production and operation instability factors. According to the scene debugging experience, the production of below 400 mesh coarse whiting powder, vertical mill slag discharge, generally for a small amount of particles and powder, at this time as long as the guarantee smooth feeding, the reasonable air volume, increasing, vertical mill run relatively stable; Production more than 600 mesh powder, the material need to cycle times in the vertical mill grinding and classification, therefore vertical mill discharge port will produce more powder, appropriate control and reasonable feed feed rate and air flow, the discharge amount is stable can be appropriately increased air volume, improving the capacity of belt material, to reduce the amount of slag discharge in differentiable increase feed feed rate, to ensure the dynamic balance of chance in internal and external circular grinding.