DE1926586B - Bearing components with self-lubricating effect - Google Patents

Description

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There are already different types of bearings which can be rigid grains with lubricating effect components with self-lubricating effect in use. either made of ceramic-like material with peculiarities Components consist, for example, of nylon, lubricating effect or of carbon containing, Metals or resin compositions in which ceramic-like material are made. Instead of this Filler particles with a lubricating effect, such as graphite 5, can also be made from a rigid resinous binder or Molybdenum disulfide, are incorporated. agents, such as epoxy or phenolic resins, or one

These known materials show, however, among ceramic-like binders consist in which finely divided high loads and high-temperature operating lubricants made of sulfides, selenides and tellurides conditions disadvantages. So tend z. B. thermoplastics from molybdenum, tungsten, tantalum, titanium, zirconium, see and thermosetting resins, at high temperatures ίο hafnium, niobium and thorium, also graphite, polyperatures to become soft and lose their support- tetrafluoroethylene and / or boron nitride are dispersed skill traits that are often required. and where optionally calcium fluoride, zinc oxide, Since no bearing component completely eliminates the friction, zinc sulfide, potassium titanate and / or antimony trioxide is always the problem of heat absorption as additives can be included. In each given in the camp. Because of the lack of firmness, the rigid grains have to be larger For many materials, the lubricant diameter must be more than 0.075 mm, and the flexible one part of the component under high load a considerable material through which they are cemented together, borrowed have a deep cross-section. That increases but that must be 15 to 35 percent by volume of the entire composite heat absorption problem, because it is difficult to identify the heat material.

derive through the bearing components themselves. In addition, the following detailed explanations are provided

Some of the resinous materials tend to be useful for a better understanding of the invention:

Time to find use under high temperature The flexible putty, in which the rigid grains

Operating conditions for breaking down what are dispersed with lubricating effect can result from

causes the component to fail. This elastomer, thermoplastic or thermosetting

Collapse often leads to a gas breakdown. The specified minimum diameter

drive, which in certain types of application knife for the rigid grains with lubricating effect

is undesirable. is both for the flexibility you want as well

A process for the production of ceramic-like bearing components with self-lubrication importance, which is crucial for the lubricating properties, has already been established. Proposed in the rigid grains with lubricating effect, according to which solid lubricating effect, the specified lubricants can be present in medium-filler particles in ceramic-like structures of finely divided form, the named being embedded. Such bearing components are lubricant additives of up to 50%, based on the weight of the lubricants, especially for use at high temperatures.
Suitable for operating conditions and high loads. The proportion of finely divided lubricants in the their lubricating effect is excellent, but they have 35 rigid grains can be between 50 and 97 Vo, the disadvantage that they are fragile and subject to harsh handling conditions based on the weight of rigid binder or by VI-f - lubricant. The rigid filler grains can break bration easily. The same also applies, for example, by coarsely comminuting large bearing components for the carbon-containing bearing components with pieces of the rigid material and then having a self-lubricating effect. 40 Fine grinding down to the desired grain size

The present invention therefore relates to bearing sizes which - as already mentioned several times - are larger

parts in which the above-mentioned disadvantages must be as far as 0.075 mm are produced. The stare

are excluded as much as possible. The invention grains with self-lubricating effect can, however

According to bearing components are under high loads also consist of a rigid structure in which liquid

functional, can easily be in a form with 45 or waxy lubricants in individual or

minimal space requirements, continuous pores are dispersed,

and the tendency to break is to a minimum. As a binder (= cement compound) for the rigid grains

degraded. elastomers are preferably used; it was

The bearing components according to the invention with their own, however, found that also flexible, thermoplastic

lubricating effect from a mosaic structure exhibiting 50 or thermosetting resins for cementing the lubricating

Composites are characterized in that medium particles can be used. Furthermore, was

the particular composite made from found that the desired properties in

(1) 15 to 35 percent by volume of a flexible cement mass composed of elastic, in some cases by adding fiber-like, marked, thermoplastic or thermosetting starch materials and / or relatively small resins, 55 quantities of finely divided lubricant particles, such as in the possibly additional lubricant Molybdenum disulfide or graphite, can be improved to the cement mass particles with a grain size of less than 0.075 mm Composite embedded fabric or reinforcement are embedded, as well as from ^6o * ^us > ⁿ , the ^same e "statistically distributed fibers, such as

_, ^& ... __. ,. . Graphite or asbestos fibers exist. When graphite

(2) in this flexible putty mass disperse rigid _{{asem in which} , the _{material is distributed}

Grains consists mm having a lubricating effect of a particle size _{and by the presence of graphite e} i _n i _{wt sse} s of greater than 0.075. _{Degree of} lubricating effect achieved.

The composite materials obtained in this way have a mosaic pattern structure that is so flexible because of its construction, composites are currently flexible polymers that they shocks and vibrations without damaging products such as organopolysiloxane elastomers, ethylene damage can absorb. Propylene-diene terpolymers, elastomeric mixed

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polymers from perfluoropropene and vinylidene- lying invention by cold pressing of the non-fluoride or polymers from 2-chloro-butadiene-1,3 cured material at much lower pressures than particularly preferred. previously possible to be deformed. Typical mosaic when using organopolysiloxane elastomers, like materials can be, for. B. be deformed at room temperature together with fillers with self- ^{lubricating effect, 5 under pressures of 70.3 kg / cm 2} , such as molybdenum sulfide and zinc sulfide, which by nature react acidic for the powdery resin structure material, it is advantageous to use a buffer Pressures of 2812 kg / cm * and more are required, substance to modify the pH value with the use of smaller presses. For this purpose, several compression molds and less massive compression molds are made possible, which makes suitable bonds, for example ethylenediamine io, leads to a reduction in costs. Except for KaItpropylttimethoxysilan. The addition of such preliminary presses can improve the mosaic-like materials due to the better adhesion of the strength properties, of course also through compression deformation in the heat, filler particles to the organopolysuoxane elasto-injection molding and extrusion molding, extrusion and chambers. The hardening of the landierverfahren and with some materials even elastomers, with pH-regulating catalysts, ig can be produced by casting,
like triethylenediamine, serves the same purpose. As already mentioned, organopolysiloxane-The flexibility and compressibility of the mosaic elastomers and some other polymers are preferred for the type of composite materials with self-lubricating properties. Production of the composite materials according to the invention has numerous advantages over those preferred for these. Of course, however, materials known to date can also be used. The composite so other materials can be used for this purpose, e.g. B. fabrics can be made in the form of fairly thin foils, the urethanes are made from mixtures of low and high, which leads to material savings. viscous diols and bifunctional or trifunctional, the known compositions have onelle isocyanates. The urethanes, however, have a self-lubricating effect, especially those difficult to handle with resins because of their rapidly combined types, a greater thermal curing time when using conventional catalysts than the metal components with which they are connected when using slower-acting catalysts and for the lubrication of which they serve. unusually long pressing times are required. This difference can cause loss of bearing. In addition, urethane elastomers tend to cause backlash. Charcoal bushings require z. B. to have considerably less stability than the one additional snug fit spacing in the holding systems preferred.

devices, because the low thermal expansion nylon is also usable, but this has the disadvantage of loosening at high temperatures part of a large heat absorption and a high level. Composites using organic resins as binding friction compared to the elastomeric Miterialien. contain agents, can expand faster It is assumed that nylon is in the than the metal fastenings and is thus forced to 35 contact with moving metal parts in a bearing on the rotating shaft or other such a high friction on the nylon surface, to remove movable parts and to cause seizure of the molten nylon bearing at these points. ; layer forms. This plastic deformation can be caused by the fact that the mosaic-like composites can be inserted into a coating of the lubricant grains through nylon in the form of thin strips, 40 which results in a layer of nylon in all and, due to their compressibility, they are capable of bearing components . In addition, nylon shows the different thermal expansion to grain - not the excellent deformation and back-pumping and so the problems mentioned - the properties of the preferred materials,
shut down. In addition to the types of application that are usually intended for bearing components, the composite materials according to the invention can also be conveniently produced for other applications. Due to their flexibility, areas can be used, such as for piston rings, and a thin film with a mosaic structure can be used in the seals. Due to the compressibility of the desired shape to be bent, so that a material it is also possible to adjust to a smaller number of shapes are required. 50 of the outside of the composite material, in order to also compensate for the heat dissipation due to the production of the composite the abrasion in different types of applications to materials with thin cross-sections. So z. B. instead of confusing a bearing component with the resin-bonded structures, as is customary at the moment. With better heat dissipation, there are only a few screws that need to be tightened to compress the composite with less heat for each coefficient of friction, creating a receptacle in the bearing. ' Repair with minimal costs and production-even if a failure is reached in application forms.

require a larger cross-section of the lubricating material.It should be noted that, in addition to the molding under pressure, various resins, elastomers, and catalysts mentioned, the use of uncured elastomers and fillers also means that further mers may be used to bind the rigid lubricant granules for ease of handling facilitates compression molding. Many of the currently available can also be used. For example, resin-like materials used can be pressed into the mold in powder form, if necessary mold release agents. This requires high temperatures and mixed in.
High pressure pressing devices. Since the uncured 65

Elastomers by nature at room temperature are an example!

is highly viscous material, the 35.3 parts by weight of an uncured ethylene prop-

meren producible composites according to the pre-ylene-diene terpolymer, 30.4 parts by weight of a

resinous organopolysiloxane copolymer made from 25 mol percent methylvinylsiloxane, 15 mol percent Monovinylsiloxane, 20 mole percent phenylmethylsiloxane and 40 mole percent monophenylsiloxane units, 21 parts by weight of one-part carbon black and 13 parts by weight of graphite fibers were on a cold Mixed two-roll mill and added 0.87 parts by weight of dicumyl peroxide as a catalyst.

The catalyzed mixture was treated with lubricating grains on a hot two-roll mill in a ratio of 15 percent by weight of polymer mixture to 85 percent by weight of lubricating grains. The lubricating grains were a mixture of 40 _{parts by weight of MoS 8} and 40 parts by weight of ZnS in 16.7 parts by weight of an epoxy resin binder which had been cured with 3.3 parts by weight of a dianhydride of 1,2,3,4-cyclopentanetetracarboxylic acid at 205 ° C. for 2 hours was. The cured material was crushed and sieved 1.4 mm to 2.0 mm and 50 ° / ₀ grain size of 0.8 to 1.4 to give 50% of the grains size.

To make it easier to disperse the solid grains with a lubricating effect in the uncured polymer mixture, the mixture was diluted by adding 5 percent by weight of heptane, which was then removed again by drying in air. The polymer-lubricant grain mixture was pressed for 15 minutes at 163 ⁰ C under pressure and post-cured for 2 hours at 205 ⁰ C. The bearing component obtained in this way was tested in a journal bearing tester in a 30-day test under a pressure of 3.52 kg / cm ² and a speed of 138.4 m / min. The pressure in the device was 3.52 kg / cm ⁸ at 1725 rpm. The constant temperature of the composite was 66 ^° C. At the end of the test, a wear of 0.17 cm and a weight loss of 2.6 g were measured. The same rigid epoxy resin binder and filler loading, but in finely divided form, were tested in an identical test. A constant temperature of 76 ° C. was obtained and a wear of 0.23 cm and a weight loss of 5.9 g were found. This proves a better resistance to wear of the mosaic-like composite than the filler with lubricating effect in finely divided form.

These two samples were also tested on the Alpha-LFW-1 tester at 40.8 kg (40.8 kg / cm ² ) load on the samples. The results are shown in Table I below.

The wear on the Alpha-LFW-1 tester was determined as follows: a cylindrical metal test block was pressed against a rotating metal test ring under the specified load. The wear visible on the block was determined in cm · 10 " ⁹ per centimeter of the ring circumference, ie the wear is measured in centimeters per centimeter of the ring that was moved against the surface to be worn. The wear determined using this method ίο is therefore dimensionless .

These tests show comparable friction and wear properties between the two Materials. However, the flexure deflection rupture indicated the breakage of the composite after a rash of 0.315 cm of a 2.54 cm wide chip compared to the flexural deflection deflection of the solid material at 0.041 cm, demonstrating the considerable superiority of the mosaic structure in the absorption of Shocks and vibrations showed.

Example 2

85 percent by weight of the rigid epoxy resin lubricant filler grains according to Example 1, in sizes between 0.82 and 0.225 mm, were with 15 percent by weight of an uncured elastomer molding compound of 100 parts by weight of polymerized 2-chloro-butadiene-1,3 (neoprene GW), 5 parts by weight of magnesium oxide and 4 parts by weight of zinc oxide mixed, ^{compression-molded at 177 ° C. for 1} _{l for 2} hours and post-cured for 1 hour at the same temperature.

On an Alpha-LFW-1 tester at 38.0 kg / cm ⁸ a coefficient of friction of 0.08 to 0.05 at 43.89 m / min, and of 0.033 at 109.73 m / min.

detected. The constant temperature was between 65 ° and 71 ° C at both speeds.

Table I.

Frictional tempera Ver coefficient door wear Rigid composite 21.95 m / min 0.08 48 ° C 1.77 87.78 m / min 0.05 82 ° C 1.43 131.67 m / min. ... 0.04 94 ° C 0.925 Mosaic-like Composite 21.95 m / min 0.11 57 ° C 5.5 87.78 m / min 0.06 93 ° C 0.925 131.67 m / min. ... 0.05 107 ⁰ C 2.7

Example 3

90 parts by weight of the rigid epoxy resin lubricant grains according to Example 1 from 60 parts of a size of 1.4 to 0.8 mm and 30 parts of a size of 0.225 to 0.075 mm were treated with an uncured elastomer molding compound of 10 parts by weight of polyisoprene, 1 part by weight of dicumyl peroxide and 0, 20 parts by weight of ethylenediaminopropyltrimethoxysilane mixed. The mixture was compression-molded for 30 minutes at 177 ⁰ C and post-cured for 45 minutes at 177 ⁰ C. The results on the Alpha-LFW-1 tester gave at 43.89 m / min, a coefficient of friction of 0.09 and a temperature of 55 ° C. At 109.73 m / min. The coefficient of friction was 0.06 and the constant temperature 68 ⁰ C.

Example 4

89.4 parts by weight of the solid epoxy resin filler according to Example 1 in grain sizes between 0.82 and 0.225 mm were mixed with 9.9 parts by weight of an ethylene-propylene-diene terpolymer, 0.40 parts by weight of dicumyl peroxide and 0.25 part by weight of ethylenediaminopropyltrimethoxysilane. The solid Epoxyharzfüllstoffmaterial accounted for 76% ^it d total volume of. The material was pressed onto a wire mesh pad to form a 0.24 cm thick film. This material was tested on the Alpha-LFW-1 tester under a load of 40.8 kg. At 21,95 m / min, the coefficient of friction 0.0666 and the constant temperature was 49 ⁰ C. at 87.78 m / min, was

the coefficient of friction was 0.0 (51 and the temperature 72 ⁰ C; at 131.67 m / min. | the coefficient of friction was 0.056 and the temperature 85 ⁰ C.

The same tests were performed on samples in which the Volumprozentgehalt of the polymeric filler 14 to 35.7 ° / ₀ varied. At 15 percent by volume, the resilience of the material became extremely low, although the lubricating properties were comparable. At 35.7 percent by volume, the sample failed due to high friction and high wear.

Example 5

A rigid lubricant was made by mixing 80 parts by weight of a finely divided MoS ₂ (Molykote Z), 20 parts by weight of a phenylmethylsiloxane resin with an average of 1.5 methyl and phenyl radicals in total per Si atom and a ratio of phenyl to methyl radicals of 1.13 to 1 , 0 and 1 part by weight of triethylenediamine produced as a hardening material for the resin. This turned into panels 0.635 cm thick χ 1.27 cm ^! Width χ 12.7 cm high, compression molded. These panels were then subjected to a reducing atmosphere at 400 ⁰ C for 2 hours, then at 60O ⁰ C for 2 hours and finally calcined for 2 hours at 800 ° C and then allowed to cool.

The ceramic-like material thus obtained was crushed and sieved to form grains with a lubricating effect with a grain size of 0.075 to 1.4 mm. 84 parts by weight of the grease grain material were with 9.2 parts by weight of ethylene-propylene-diene terpolymer, 5.5 parts by weight of finely divided graphite, 1.0 part by weight of dicumyl peroxide and 0.25 part by weight Ethylenediaminopropyltrimethoxysilane mixed and cured.

The test on the Alpha LFW-1 test apparatus under 40.8 kg load showed a coefficient of friction of 0.167 and a temperature of 55 ⁰ C at 21.95 m / sec., 0.0444 coefficient of friction and 60 ⁰ C at 43.89 m / sec. and 0.0611 coefficient of friction and 71 ⁰ C at 87.78 m / sec. j

Example 6

Ceramic-like rigid material was prepared according to Example 5 and sieved using the following components:;

(1) 40 parts by weight of MoS ₂ , 50 parts by weight of zinc oxide and 20 parts by weight of phenolic resin and

(2) 70 parts by weight MoSi and 30 parts by weight Phenolic resin. j

The molding compositions were pressed under pressure, fired, comminuted and sieved, as in Example 5, instead of the ceramic-like filler used there in the same ratio. The results of the test on the Alpha-LFW-1 test device can be seen in Table II: \

Table II

Table II continued

Mosaic-like
Composite

21.95 m / sec.

43.89 m / sck.

87.78 m / sec.

Coefficient of friction

0.145
0.111
0.072

temperature

51 ° C
63 ° C
71 ⁰ C

Rigid composite

21.95 m / sec

43.89 m / sec

87.78 m / sec

Coefficient of friction

¹ 0.167 j 0.103 i 0.067

temperature

55 ° C 63 ° C 74 ⁰ C

Example 7

The zinc sulfide was each replaced by calcium fluoride, zinc oxide and antimony trioxide as a lubricating filler of the rigid material in the previous examples, equivalent results were obtained.

Example 8

Instead of molybdenum disulfide in Example 1, boron nitride, polytetrafluoroethylene, graphite and wool-fram disulfide were used used, practically the same results were achieved.

Claims (4)

Patent claims: 1. Bearing components with self-lubricating effect made from composites with a mosaic structure, characterized in that the respective composite consists of (1) 15 to 35 percent by volume of an elastomer, thermoplastic, or thermoset Resins composing flexible putty mass, in which optionally additional lubricant particles with a grain size of less than 0.075 mm in quantities of up to 50%, based on the weight of the flexible putty, and / or a fiber reinforcement are embedded, as well as from (2) Rigid granules having a lubricating effect dispersed in this flexible putty compound Grain size larger than 0.075 mm. 2. Bearing components according to claim 1, characterized in that the rigid grains with The lubricating effect of a grain size larger than 0.075 mm consists of a rigid binding agent, wherein lubricants made of graphite, polytetrafluoroethylene, boron nitride and / or sulfides, selenides and tellurides of molybdenum, tungsten, titanium, tantalum, zirconium, hafnium, niobium and thorium Are dispersed, the lubricant content 25 to 97%, based on the weight of rigid Binder + lubricant, and that the lubricants may also be finely divided Calcium fluoride, zinc oxide, zinc sulfide, potassium titanate and / or antimony trioxide in amounts up to 50% »based on the weight of the lubricants. 3. bearing components according to claims 1 and 2, characterized in that the fiber reinforcement from a fabric embedded on the surface of the composite or from in the composite randomly distributed fibers. 4. Bearing components according to claims 1 and 2, characterized in that the respective composite as flexible putty masses organopolysiloxane elastomers, elastomeric ethylene-propylene-diene terpolymers, elastomeric copolymers of perfluoropropene and vinylidene fluoride or polymers of 2-chloro-butadiene-1,3. 109534/366