CNC vertical lathe overhaul case analysis
CNC vertical lathe overhaul case analysis release time: 2018 - 01 - 19 clicks: one, 3827 times before the overhaul CNC vertical lathe, found the following main problems: 1, the workbench static pressure up uneven. 2, the precision of the spindle radial and axial precision is not up to standard. 3, beam clamping problems. 4, beam lifting lead screw nut wear tests. 5, beam level cannot meet the needs of the machining accuracy. Second, nc vertical lathe overhaul construction repair plan: 1, on the workbench static pressure uneven float adjustment scheme table adopts separate structure, separation around the column and table base, table base guide part and spindle separation, workbench USES short spindle structure, radial double row cylindrical roller bearings with high precision centering, the inner ring with a taper hole, can adjust radial clearance, to ensure that the spindle rotation accuracy of axial pre-tightening load: the constant current static pressure guide rail, oil by high precision for the oil flow, such as, a total of 24 static pressure oil cavity. Workbench guide principle of static pressure system: tank & rarr; Oil suction filter & rarr; Gear pump & rarr; Paper filter & rarr; The overflow valve & rarr; Globe valve & rarr; Amount of points. Workbench static pressure device working pressure are set in the relief valve. Set methods for static pressure oil pump work after close the cut-off valve, and then adjust the relief valve to the set pressure, then open the valve. To clean the oil, every pump outlet is equipped with paper filter with the differential transmission device. When the differential transmission device alarm, 10 - at this time should be delay 20 seconds to stop and clean or replace filter in a timely manner. Amount of points is the static pressure pump oil machine provides the oil amount to 24 working oil cavity. Is monitoring the hydraulic oil flow transmission device is enough, if too little oil emit signals, workbench is not allowed to turn right now, otherwise will grind the workbench. Workbench hydrostatic oil film floating up by three electric displacement sensor monitoring, when the workbench floating appreciation is less than 0. 4 mm when issued a report to the police. 2, recovery precision of the spindle radial and axial adjustment precision of spindle bearings and tapered roller thrust bearing, the goal is to reduce the bearing clearance, ensure the accuracy of the workbench radial and axial precision due to the main shaft bearing inner ring hole is cone hole, can produce radial deformation when bearing inner ring downward adjustment, so as to adjust the fitting clearance of bearing roller and the inner and outer ring. The workbench and pre-tightening force is in order to improve the axial stiffness of the workbench and ensure cutting workbench have enough resistance torque. To ensure that the axial accuracy of workbench. Workbench spindle bearing adjustment and preloaded in accordance with the following steps: the precision of the spindle radial adjustment:, in turn, remove the end cover, flange, encoder, cover, gland, adjusting pad, bearing, pressing sleeve, tapered roller bearing; In remove the adjustment pads, with screw fastening gland and measurement after adjusting pad and the distance between the spindle bearing inner ring, coarse adjustment to adjust pad makes gland and the distance between the spindle bearing inner ring for 4 - 5 mm, then according to the gland and the spindle bearing inner ring between the actual value adjustment to adjust pad. The adjustment after the installation of tapered roller bearing and pressure, and then to adjust the pad to adjust. Spindle axial precision adjustment: to increase the oil film of hydrostatic guideway stiffness, high precision thrust tapered roller bearing should be adjusted, the adjustment method is as follows: remove the adjustment pads, installed after the gland contacts of the dial indicator on the work you and open the workbench static pressure oil pump, when the workbench of the rules for hydrostatic guideway access to tighten the screws evenly after pressure oil slowly, until the dial indicator shows the workbench can't measured at 0. When stop around 13 mm, adjusting for gland position to adjust pad. 3, fix beam clamping beam six clamping point. When the beam is in a state of clamping, pressure oil into the oil cylinder, push the pistons, oblique iron ( Slope 1:10) To the clamping mechanism of internal movement, pressure plate to relax. Oil cylinder profile of micro switch signal, beam lifting motor can start ( Electric interlocking) But when the pressure oil into the move to the clamping mechanism of the external oblique iron piston, clamping beam. When need to adjust the clamping piece and column guideway clearance ( Relax) , may be adjusted according to the following method: a, first the control of the elevator motor fuse, or will be loaded in the micro switch on the side of the oil cylinder contactor release, make the beam lifting motor cannot be started; B, according to the beam lift button, pressure oil into the oil cylinder, relax the beam state ( The beam cannot lift) ; C, budge clamping mechanism of occlusal nut, adjust; D, will fuse in again or to reset the micro switch. 4, regular check beam lifting lead screw nut wear inspection method is: the bottom of the beam lifting lead screw nut is equipped with an insurance nut, in machine tool factory, the gap between the two nut to 5 mm, must check the clearance value in use. When the clearance value is close to 3, then the thickness of the nut thread worn close to 2 mm. The nut can not continue to use, must replace the new nut, otherwise will be caused by wear nut bar the risk of loss. 5, adjustment of beam horizontal precision beam horizontal position is through the beam and column of the left and right sides of the nut and screw hanging at the top of the column on the worm gear box below, out of a drive shaft and two worm gear box beam lifting motor connection, if the spin a shaft side beams can be obtained rise or fall, the purpose of adjusting the precision of beam. Adjust, loosen the set screw, exit coupling, according to need direction of rotation screw, set after installed coupling, will set screw tightening.