SU1640607A1 - Sliding-contact bearing friction and wear test device - Google Patents

Abstract

The invention relates to devices for testing friction bearings and wear bearings for oil-filled spindles of turbo drills. The aim of the invention is to increase / /// // // / - / // l //// // / 12 11 14 29 IS 5 8 1 1 1545 16 12 1110 Fig. 2 Reliability of the results On the holder 6, assembled, install the left rubber-bearing bearing 5 with the bracelet 29 and the collar 28 on the collar, and put the glass on the sleeve 5 After crimping 28 the internal cavity of the sleeve 5 is filled with lubricant. Then set right After that the camera 3 is mounted on the holder 6 and the subsequent installation in the body 2, the cavity of the camera 3 is filled with the drilling fluid. The sliding bearing is loaded, the holder 6 is rotated with the counter-specimens 7 and recorded the moment of strength of friction and the wear of 1 z p f-ly 4 il / - / 5 Е (О (о VI

Description

The invention relates to the testing of materials, in particular sliding bearings, with respect to the operating conditions of the oil-filled spindles of turbo-drills.

The purpose of the invention is to increase the reliability of the test results of sliding bearings with coaxially mounted collar collar outside of the rubber-metal bushings by sealing the bearing cavity with lubricant, which prevents the external environment (drilling mud) from entering the cavity.

FIG. 1 shows a device for testing sliding bearings: FIG. 2 shows section A-A in FIG. one; in fig. 3 cross-section of the lip seal; in fig. 4 - shaped bracelet.

The device comprises a base 1, a body 2 fixed on it, a hermetic chamber 3 and a holder 4 of a sleeve bearing 5. The holder 4 is made in the form of a glass with through longitudinal grooves (not shown) on its outer surface, through which the drilling fluid (external environment) passes. In the bores of the housing 2, the holder 6 of contra-snipers 7 are mounted for rotation, which are bushings fixed by a pin 8, tightened by a nut 9 through the sleeve 10. Holder 6 is connected to a drive (not shown). Bearing sleeves 5 are made in the form of two coaxially mounted in blind sockets (not shown) of the cup 4 rubber metal bushings with collar collar out. The sealing of the inner surface of the chamber 3 is provided with side covers 11 with gaskets 12, cuffs 13 and sealing rings 14 and 15. Two fittings 16 are embedded into the wall of chamber 3 for supplying and discharging the external environment, and a bracket 17, which interacts with the process of working with strainer 18 means of recording the moment of friction. The signal from the strain gauge, proportional to the friction force, is fed through an amplifier to a recording device (not shown). The device comprises means for detecting the rotational speed of the counter-sample holder 6, which are a slotted disk fixed on the holder and an inductive sensor mounted in series (not shown).

The radial loading mechanism is a balanced lever 19, hinged to the faceplate 20, which, in turn, is centered in glass 21 using

the bushings 22 are axially spring-loaded by the spring 23 and are limited in height by a stop (not shown) fixed to the rod 24. The normal load created by the weights 25 is transmitted to the bearing via a self-aligning rod 26 interacting with the bearing sector 27 rigidly fixed on the outer camera surface 3.

Rubber-metal bearing bushings 5, imitating natural radial bearings of turbo-drills and spindles in their support part, are installed

5 collars outward, which are crimped by collars 28 through profiled bracelets 29. Each of the bracelets has staggered on both sides and with an overlap in height h

0 slits, the width a and pitch t of which is chosen from the condition of ensuring the tightness of the internal volume of the bearing bushings 5, preventing the lubricant from leaking out of this volume, ensuring that the lubricant (but not abrasive) does not get onto the rubbing surface of the collar from the outside and prevents its premature wear . Since the length I of the bracelet 29 in its initial (uncompressed) state is somewhat less than the circumference along the outer surface of the collar (by the amount C), when the yoke 28 is tightened, the elastic collar is crimped along counterpiece 7 and the contact pressure diagram is discrete. In the general case, vary by the parameters a, h and t, i.e. by the coefficient of mutual overlap KW, it is possible to change the size and nature of the distribution of pressures on the surface of the friction.

0 The same crimping of the bracelets 29 is achieved by installing dimensional sleeves or a set of washers between the ears of the collar (not shown).

If it is necessary to record the temperature in the zone of friction and ambient temperature

5, thermocouples (not shown) are installed in the hermetic chamber 3 through fittings 16.

The assembly of the device is carried out in the following order. First, the left side cover 11 with the gasket 12, the sealing lip 13 and the sealing ring 14 are successively mounted on the holder 6 with the bearing bearings installed on it, and then the samples 7 fixed to each other by a stepwise undercut of the counter 5 and fixed by a pin 8 through the free a pin hole communicating with the central internal channel of the holder 6. On the holder 6 assembled in this way, put on the left side of the sleeve a bearing sleeve 5 s

pre-installed on its collar collar with a shaped bracelet 29 and collar 28, and on sleeve 5 all the way into the beaker 4 with pre-installed sealing rings 15 in its inner grooves. After clamping 28, the internal cavity of sleeve 5 is filled with grease, for example, dipping . Then the bearing sleeve 5 is installed right up to the stop in the bead of the glass 4 as well as the left outward with a collar and both of them are locking hardware with set screws relative to the glass 4. After oil is poured onto the inner cavity with bracelets 29 so that Cup 4 with sleeves 5 rotated relative to the counter-specimens 7, but oil leakage must be excluded. This is ensured by the fact that in the crimped state, the plot of contact pressures under the bracelets 29 is not uniform, but discrete. Under the slits, the contact pressure drops almost to zero and lubricant may leak in the friction zone, and since these slits are located on both sides in a staggered manner and with overlap in height, the inner surface of the collar is permanently lubricated.

A sealing ring 14 is put on the holder 6 up to the stop in the right sleeve 5. Then the subassembly is fixed inside the chamber 3 with a screw, and the side covers 11 are screwed onto it. On the holder 6 side, the sleeve 10 is installed with rolling bearings and all the assembly is tightened nut 9. The channel of the holder 6 is filled with oil and closed with a stopper (not shown)

The chamber 3 with the holder 6 located inside it is installed in the bearing seats of the housing 2, after which the rolling support bearings are rigidly clamped with covers (not shown), and the holder 6 is connected to the drive (not shown) through the coupling. The device is disassembled in reverse order. The assembled chamber 3, connected through the cup 4 with the test bearing sleeves 5, the sealed internal cavity of which is filled with lubricant, has the ability to rotate in a circumferential direction relative to the counter-specimens fixed on the holder 6 when the holder 6 is rotated and the chamber 3 is rigidly fixed on its outer the surface of the bracket 17 is carried away in the same direction by the forces of friction arising in the bearing and sleeve parts of the subjects

The sleeves of the sleeves of the cuffs 13, however, the resistance of the bearing sector 27 and the stop in the form of a strainer 18, the deformation of which is a measure of the resistance to this rotation, i.e. measure of strength of friction.

Thus, the frictional force moment (Mt) measured by a strainer of 18 is added up from 0 Mt Mp + Mm + Mm + Mssh.

where Mp is the moment of friction forces in the bearing (supporting) part of both sleeves 5;

Mmf moment of friction forces under the cuff collars of both sleeves 5; 5Mm - the moment of training on the holder 6

two sealing cuffs 13;

The mssh is the moment of friction from the interaction of the self-aligning rod 26 with the bearing sector of 27. 0 Mm and Mssh are determined in advance during calibration. Then, experiments are carried out in two stages (with unpressed and compressed cuff collars). With constant required P and V, the friction losses from each of the parts (bearing and sleeve) of the sleeve 5 are differentiated and, accordingly, the gap (or tension) of the sleeve and the compression force of the short-wave of the bracelet change its width and Other 0 factors for the sleeve sleeve.

In the first case (with open collars)

(Mm + Mssh).

In the second case (with crimped collars), Mp with zx

Mwm Mt-Mgg (Mm + Mssh)

Knowledge of these moments makes it possible to determine the specific friction forces on each of the sections of the test bearing 5 and, through them, proceed to the calculation of the moment of friction in full-size radial supports of this type.

The wear of the counterpiece 7 is determined by profilography separately under

5 supporting and cuff sections of the rubber-metal sleeve 5. and its wear - by weight or micrometric methods.

The device works as follows. Holder 6 with assembled on it

A sealed chamber 3 and support bearings are installed in the support sockets of the housing 2, connected by a rotary coupling and clamped with bearing caps. With this bracket

5 17 through the ball acts on the strainer 18. The rod 26 is installed in the hole of the faceplate 20. Turn the faceplate 20 with the arm 17 pivotally attached to it until the rod 26 is installed on sector 27. Setting the rotation to holder 6. at the end

The lever 19 hangs the load G, gathered under the condition of creating the required contact pressure, after which the rotational speed is finally set. During the test, the moment of friction, the rotation frequency of the holder 6, the temperature are recorded, and the wear is determined after the tests.

Claims (2)

Claim 1. Device for testing friction and wear sliding bearings, comprising a base, a housing fixed on it, mounted in a housing so as to rotate a counter-specimen holder with a drive and a sealed chamber enclosing the holder for fitting into its cavity and withdrawing the working medium located inside the chamber is a bearing bush bearing, a radial loading mechanism, made in the form of a lever with weights and a rod, mounted on the outer surface of the camera is a bearing sector p and means of measuring the frequency of rotation of the counterbrazier holder and the moment of friction, characterized in that, in order to increase the reliability of the results of testing the sliding bearings with rubber-metal coaxially mounted collar collar out bushings, the sleeve bearing sleeve holder is made in the form of a cup fixed inside the chamber with through longitudinal grooves on its outer surface and with blind cylindrical sockets on both ends, the device is equipped with means of adjustable crimping of sleeve collars made in the form of collars seizure of the corresponding collars through profiled bracelets, which are made in the form of split holders with cuts at both ends, arranged in a staggered order and with overlap in height. 2. The device according to claim 1, characterized in that, in order to reduce the test time, it is provided with a glass fixed on the basis of such in such a way that its axis is perpendicular to the longitudinal axis of the contrash-holder mounted in the glass using a centering bushing with a spring-loaded faceplate hinge support for accommodating the lever of the radial loading mechanism and guiding hole for accommodating the radial loading rod in it. 18 -z20 L. h "about : Figz 4