Hot sawing machine spindle bearing lubrication way improvements - bearing knowledge

In the rolling workshop is the special steel plant in lai steel are the main bar production workshop, its hot sawing machine for hot rolled round steel of key equipment. Due to the hot sawing machine failure rate is high, become the bottleneck of restricting production of steel rolling. One, the problem of hot sawing machine spindle bearing lubrication method used in 50 # machine oil oil bath lubrication oil pool, machine oil on the bearing lubrication effect is good, but serious, each all needs to shift to join a bucket in the headstock ( 12公斤) Oil, annual consumption of 12. 96吨。 Oil spill with the saw blade cooling water discharge, severe environmental pollution. Due to the oil spill quickly, bearing damage rather than sufficient lubrication; Often the oil ignition in the headstock, also cause downtime. About half the spindle bearing damage due to bad lubrication, the annual average downtime 20 h, become the persistent ailment of the production. Looking for oil spill reason for spindle box structure diagram as shown in figure 1. There are two main ways to spill: ( 1) Part of the oil along the shaft seal leakage. Hot working process for periodic reciprocating saw steel back, make the oil oil level in the headstock wave motion, and the amplitude is bigger, lead to oil leakage along the shaft seal gap. ( 2) Another part of the oil from the spindle box sand holes, porosity and crack and leakage. According to the conventional way to strengthen the shaft head seal on the box body defect welding repair for many times, had no obvious effect. Technical analysis hot saw saw steel, bearing great instantaneous impact load, impact load will be formed in the instantaneous great pressure, reciprocating and intermittent movement against the oil film formation. Spindle box under the steady baking hot steel become drier, making machine oil temperature rise caused by lower viscosity, to some extent, affect the service life of the bearing. According to theoretical analysis and calculation, the main shaft bearing can be used dry oil lubrication, at the same time also can simplify the structure of bearing lubrication device and sealing device. Dry lubrication can be used to work under high pressure, high temperature of friction surface, but also lubrication with varying load, vibration and impact of mechanical friction pair. MoS2 lithium base grease lubrication properties of water resistant and cold resistant, high temperature resistant, good chemical stability, drop point 170 ℃, 375 (penetration 1/10) mm。 At the same time, MoS2 lithium base grease has a lower friction coefficient and good adsorption and wedging, viscosity and very soft, oil by impact load in the bearing is easier to form the oil film. Studies choose YanHua group tianjin lubricating oil co. , LTD production of 'jin fat' brand MoS2 extreme pressure lithium base grease. Technical measures, See figure 2) ( 1) In two bearing has a transparent cover on one side of the ring groove processing, facilitate and bearing cover meet installation position. ( 2) The processed the two bearing on one side of the transparent cover on the spindle assembly fashion to the shaft. ( 3) The assembly good hot saw the main shaft hoisting in place, make corresponding card into the corresponding two bearing, bearing the two bearing cover card table in the inner ring groove. ( 4) Bearing in adding suitable amount of MoS2 extreme pressure lithium base grease, keep bearing roller and rack is full, then cover the bearing cover, put the screw fastening. ( 5) Remove the original cover with spindle box is big, easy to observe the tally and fastening screws, etc. A preliminary calculation grease replacement time of up to 240 days. Spindle bearing lubrication MoS2 instead of extreme pressure lithium base grease, a cover body temperature ( In the summer) Can be stable in 50 ℃. The spindle run very smoothly. Use to 8 months still not damaged, in order not to cause downtime, tentatively for 8 months to replace new bearing and grease. Simplify the structure of the bearing seal at the same time, easy to maintenance.