Cement slow end bearing shell temperature analysis and processing

Cement slow end bearing shell temperature too high 2020 - analysis and processing 03 - Good you-fang li (26 floor Zhejiang tiger eagle cement co. , LTD. ) My company has three & Phi; 3. 2 m× 13 m edge transmission of cement mill, bearing shell through the GDY - 25 thin oil terminal, use N320 number of extreme pressure gear oil for lubrication. Early production, the adoption of open flow process, not with roller press system, production around 50 t/h, cement grinding temperature 90 ℃, the ground wind temperature 85 ℃, basic guarantee grinding end bearing shell temperature below 55 ℃. Running two years later, no. 2 and no. 3 mill equipped with roller press system, output rose to 75 t/h, cement grinding temperature 110 ℃, the blast temperature 95 ℃. High temperature in the grinding mill often end bearing ( More than 65 ℃) Jump stop, especially the summer high temperature mill continuous running, when the temperature of the bearing is set at 70 ℃ and jump stop, seriously affected the mill production. 1 problem analysis and solution to the problem analysis, equipped with roller press system, increase production, discharge temperature of cement obviously increased, grinding in a large number of high temperature material with heat transfer to the external surface of bearing, although between hollow shaft and spiral cone winding 5 mm thick thermal insulation material, but external water and oil cooling cannot take away the new increase part quantity of heat, leading to high temperature. Ever taken for bearing internal, inspection station system cleaning and changing the measures such as lubricating oil, but can't completely solve the problem of bearing temperature is too high. Finally, in the summer of 2010, we refer to the thermos heat preservation principle, at the end mill hollow shaft spiral cylinder is equipped with a heat insulation sleeve, using air and heat insulation, try to reduce the material to transfer heat. And in the lubricating oil station equipped with heat exchanger, lube oil cooling. 2 2 transformation process. 1 add insulation hollow shaft with heat insulation sleeve structure as shown in figure 1. With 10 mm thickness, materials for Q235 steel, rolled to a ( Two and a half) Heat insulation sleeve body, and then rolling & 60 deg; Tapered flange ring into the material side, cone makes the material flow, the purpose is to reduce the resistance between the welding connection. In the interim of discharging cover the lateral cut a round hole, Or round hole) , aperture slightly bigger than a heat insulation sleeve, for it is advisable to enter the installation. Heat insulation sleeve from the hole, welding assembling the entire heat insulation sleeve, at the same time, in the mill end insulation sleeve lining length is 400 mm on welding article 3 ~ 4 spiral blade. The blades of screw barrel ( Only a third the length of the spiral tube length Don't have to cut out, and can be used as a heat insulation sleeve supporting part. In general, insulation gap, the greater the effect is better, but by an influential for the material, can according to the spiral vane height ( 80 ~ 100毫米) Determine the heat insulation outside diameter, 100 mm insulation clearance, with convenient installation advisable. After adding heat insulation sleeve, although the ventilation area is less, but increasing the material flow rate and will not bring adverse effect to production. In addition, in the original spiral tube and heat insulation sleeve clearance with a (galvanized pipe as the cooling air duct, the pipe through the discharging, into heat insulation cover inside, into the length of the original spiral tube, about two-thirds will be subject to not encounter spiral blade, the other end fixed installed in the discharge welding. Such a fixed cooling duct to the mill hollow shaft of the rotating heat insulation sleeve air natural ventilation with external temperature inside the peripheral clearance, in order to reduce the air temperature in the insulation clearance. 2. GDY - 2 add heat exchanger 25 dilute gas station oil cooling for shell and tube heat exchanger, the heat transfer area of 3 m & sup2; 。 To feed, back to the original, all the way with a pipe, a jacketed pipe water to reduce the oil temperature processing, but the effect is not ideal. Later on thin oil terminal flowline series of plate heat exchanger ( Type of BR - 0. 1, so the heat exchange area of 10 m & sup2; ） Oil supply of grinding end bush for cooling. 3 the reform step by step implementation effect. After adding heat insulation sleeve and bearing shell temperature decrease for at least 5 ℃, greatly improve the mill running status. Equipped with heat exchanger in the gas station, can directly reduce the oil temperature 5 ℃ above, improve the cooling effect, further reduce the bearing shell temperature. Completes the maintenance work at ordinary times, the runtime as long as the oil, water continuously, mill bearing shell temperature basically stable in high temperature season under 60 ℃. In recent years, there was no grinding machine due to bearing shell temperature high jump phenomena. 4 run maintenance experience on mill bearing shell temperature too high, in addition to take appropriate reform measures, what is more important in the operation of maintenance, maintenance we experience: 1) Every year during overhaul, the mill bearing inner surface, bush, dilute oil cleaning and inspection station system adjustment, and replacement lubricating oil or filter the reoccupy after processing. 2) According to water quality status, regularly, Such as half a year) Check the cleaning pad cooling water and cooling water heat exchanger tube fouling gas station, dredge pipes to ensure the best cooling effect. Clean-up can ask professional personnel for cleaning unit, also can be simple homemade a oil tank, oil pump and cleaning fluid device connected to the cooling and lubricating system of cleaning cycles. 3) Check the electric control system, such as bearing accuracy calibration of measuring points and the end resistance to avoid misunderstanding of false signal, and the pressure, temperature and flow control instrument, such as reliable and accurate protection. （ Source: China cement spare parts network)