Home>Bearing knowledge>Some experiences in repairing grinding machine hydrostatic bearings

/*728*90 created on 2018/5/16*/ var cpro_id = "u3440131";

Some experiences in repairing grinding machine hydrostatic bearings

Source: Bearing network time: 2018-01-22

/*250*250 was created on 2017/12/25*/ var cpro_id = 'u3171089';

Hydrostatic bearings are widely used in M210, M131W, 3160A grinding machines and 2A710, FYT10 diamond boring heads due to their high reversal accuracy, good rigidity, high bearing capacity, no wear and high durability. Followed by CNC technology; static pressure Bearings are also widely used in the machining of spindles for CNC machine tools in the middle. One of the top engine plants of the company; there are many static pressure grinders and static pressure diamond hoes; some investigations and tests were carried out during the repair; several experiences were obtained.
1. The small hole saver (1) changes the internal saving to external saving; and the pressure gauge is used to instantly display the upper and lower chamber pressures, which makes the repair and maintenance convenient; especially, it can be easily cleared regularly; this is unmatched by the internal saver.
(2) Saving ratio. The theoretical value of the saving ratio Î² is between 1.2 and 1.5; and based on the experience of many years, it is preferably 1.25. This is in repair; requires a few precisions on the spindle, front and rear bearing pads. Strict control of precision, concentricity, roundness and taper; in order to ensure the beta value. According to the load of the machine tool, the e value (the amount of misalignment between the main shaft and the bearing bush) can be determined; the Î² value is optimal.
(3) When the oil chambers are not equipped with the main shaft; the oil columns of the respective oil outlets must be common (observation method); if they are not common; the method of changing the aperture of the saver should be adopted; change the flow rate. Take 4 chambers as an example; Usually, the oil column of the lower, left and right chambers is between 20 and 25 mm; the diameter of the small holes is from 0. 25 to 0.4 mm.
2. The film reaction saver film reaction saves the bearing stiffness is very large; but the machine tool often exhibits the appearance of tiling, pulling, and falling pressure during the operation. The most important factor in the film reaction is the film; in practice, the bearing is locked and napped. The primary reasons are: 1 caused by plastic deformation of the film, 2 slow reaction. When the external load suddenly changes; when the film has not reacted; the axis and the tile are now in conflict, 3 the film is tired. The film is used for a long time; fatigue deformation; Changed the reaction parameters.
Adding the thickness of the film and changing to some fatigue-resistant materials; can receive outstanding results. Usually the rigid film, pre-loading, and clearance are used. The detailed method is: change the film of 1.4mm thickness to 4mm Thick rigid film; è…”äºº cavity pad 0. 05mm thick tin foil paper; the spindle is adjusted to a height of 0.05 mm higher than the azimuth orientation. The intention is to force the spindle (grinding wheel component, cutting force); just return to the middle of the ambition.
3. The oil supply system improves the static pressure bearing oil supply system; except for coarse filtration and fine filtration; other components have the effect of guaranteeing the hydrostatic bearing. The oil supply system is improved on the basis of the original system.
(1) After the plate is saved, the pressure port is connected to the pressure relay and the pressure gauge (originally in front of the accumulator); this allows the operator to see the cavity pressure and the inlet pressure. When the pressure difference is greater than a certain value; Stop immediately; prevent the axle from locking. For example: the inlet pressure is 2 MPa; the outlet pressure is 1. 2 to 1.6 MPa; less than 1.2 MPa is to stop.
(2) Adding digital detection equipment The static bearing of the hydrostatic bearing has a gap of 0. 04 ~ 0. 05mm; the oil in between has a certain resistance value; detecting the change of this resistance; The size of the gap. The main axis is one pole; the bearing bush is the other pole; the resistance value is measured. This signal is sent to the photoelectric alarm and the control system amplifier; the spindle motor is controlled to start and stop; The conflict of the tile.

Recommend to friends comments close window

Bearing related knowledge

How to adjust the clearance of SKF bearing operating conditions and environmental conditions by manipulating the preload of the bearing
Characteristic Analysis of Rolling Noise of NSK Bearings Linear Bearing LM and LME Codes Basic Meaning Sliding Bearings Overview

This article links to http://
Please indicate China Bearing Network http://

Previous:The influence of bearing layout on oscillation and noise Next edit: Key analysis of bearing selection

Bibcock

Zhejiang minmetals huitong import and export Co., Ltd , https://www.zjminmetals.com