CN104395442A

CN104395442A - Anti-fretting additives for non-lubricated contact surfaces

Info

Publication number: CN104395442A
Application number: CN201380015560.8A
Authority: CN
Inventors: G.多尔; P.德雷施勒; C.黑格尔; R.埃文斯; P.施勒
Original assignee: Timken Co
Current assignee: Timken Co
Priority date: 2012-03-22
Filing date: 2013-01-24
Publication date: 2015-03-04
Also published as: JP6130902B2; EP2828366A1; WO2013141959A1; JP2015519468A; US20150093065A1

Abstract

An anti-fretting rust preventative solution includes a rust preventative fluid and an anti-fretting additive dissolved in the rust preventative fluid. The anti-fretting additive includes at least one compound that is surface-active with steel to produce a low-shear velocity accommodation layer in a metal-to-metal interference fit. The anti-fretting rust preventative solution can be provided in a bearing assembly with metal-to-metal interference fits, as well as other applications where fretting wear may otherwise occur.

Description

For the antiwear additive of unlubricated surface in contact

the cross reference of related application

This application claims the right of priority of the U.S. Provisional Patent Application numbers 61/614,364 submitted on March 22nd, 2012, its full content is incorporated herein by reference.

background of invention

The present invention relates to the process to unlubricated surface in contact, such as, " fixing " metal-metal joint in Bearing assembly, the outside surface of the axle such as allocating interior annular distance into or the outer shroud allocating shell into.These " fix " the general press-fit of joint or shrinkage fit together, are generally intended to the movement eliminated therebetween.Utilize the bearing of aperture size, reach enough shrink-fit (being sometimes referred to as wringing fit) to prevent or to stop fretting wear not to be challenge usually.But utilizing macropore bearing to reach enough shrink-fit may be significantly more difficult.Because some torque of Bearing assembly run duration and/or vibration occur, repeatability vibration by a small margin may be there is move between the surface of shrink-fit.In these cases, by Rough Contact (contacting asperities) adhesion and break and cause fretting wear.Fretting wear also by being oxidized or corroding expansion, then can show as abrasive wear.Therefore, fretting wear is the common issue of inner ring and outer shroud shrink-fit in macropore bearing.Fretting wear also can cause by corroding and abrasive damage and/or kill assembly by the adhesion between parts and welding.

To mismatch with running clearance (running clearance) due to surface in contact and generally must not mutually relatively rotate, therefore, fretting wear can not be prevented with commercially available lubricating oil or lubricant.Therefore, these surface in contacts representative " doing " friction condition.Generally speaking, the sole material existed in metal-metal joint is the thin slushing oil coating applied after fabrication.But slushing oil does not significantly protect surface to avoid the character of fretting wear damage.For reduction macropore bearing fretting wear risk, the standing procedure that some bearing manufacturer use applies low-friction material coating, thus cover the metal bearing ring surface being easy to fretting wear.Such as, the coating based on Teflon or the coating based on chromium can be provided, to avoid real metal-metal contact.Although think that these coatings effectively reduce fretting wear risk, adding coating is expensive to neck collar, and increases the complicacy of manufacturing processed.

summary of the invention

In one aspect, the invention provides one and to resistance to wear (anti-fretting) rust inhibiting solution, described in the rust inhibiting solution that resistance to wears comprise antirust fluid and be dissolved in the antiwear additive of antirust fluid.Antiwear additive comprises at least one and has surface-active compound for steel, to produce low shearing speed regulating course in metal-metal shrink-fit.

In yet another aspect, the invention provides a kind of Bearing assembly with antiwear properties.The rust inhibiting solution that resistance to wears that Bearing assembly comprises axle, is fixed to the inner ring of axle, comprises the shell in hole, is fixed on the outer shroud in shell aperture by the second shrink-fit and provides at least the first and second shrink-fit by the first shrink-fit.The rust inhibiting solution that resistance to wears comprises antirust fluid and is dissolved in the antiwear additive of antirust fluid.Antiwear additive comprises at least one and has surface-active compound for steel, to produce low shearing speed regulating course.

By considering to describe in detail and accompanying drawing, other side of the present invention will become apparent.

accompanying drawing is sketched

Fig. 1 illustrates conformal fretting wear test (conformal fretting wear test) friction results of 5% triisopropyl borate ester in slushing oil.

Fig. 2 illustrates the conformal fretting wear test temperature result of 5% triisopropyl borate ester in slushing oil.

The illustrative of conformal wearing test that Fig. 3 illustrates 5% triisopropyl borate ester in slushing oil gathers.

Fig. 4 is the skeleton view of conventional bearings subassembly.

detailed Description Of The Invention

Before any embodiments of the invention are explained in detail, should be appreciated that, the present invention is not limited to the described or structure detail shown in the following drawings and arrangement of components in the following description in its application.The present invention can have other embodiment, and can implement in every way or carry out other embodiment.

Fig. 4 illustrates a kind of typical Bearing assembly 10, and described Bearing assembly 10 comprises inner ring 12, the axle 14 be fixed in the hole 12A of inner ring 12, outer shroud 16 and have the shell 18 of the hole 18A wherein fixing outer shroud 16.Inner ring 12 and outer shroud 16 have low friction coupling betwixt, such as rolling element (not shown).The hole 12A of inner ring 12 has the shrink-fit with axle 14, to stop the relative rotation between inner ring 12 and axle 14.Equally, outer shroud 16 has the shrink-fit with the hole 18A of shell 18, to stop the relative rotation between outer shroud 16 and shell 18.Shrink-fit reaches by press-fit or shrinkage fit.In any one situation, the shrink-fit between inner ring 12 and axle 14 and both the shrink-fit between outer shroud 16 and shell 18 all can obtain metal-metal surface contact.In some constructions, Bearing assembly 10 can hold subassembly for large-size axis parts, and wherein the hole 12A of inner ring 12 is greater than about 200mm.Should be appreciated that, some application only may need a neck collar, is therefore that monometallic-metal interference coordinates.

In order to prevent or stop at least at inner ring and outer shroud 12, the corrosion on 16, the surface of inner ring and outer shroud 12,16 provides antirust (RP) fluid.RP fluid also may be provided on axle 14 and shell 18 one or both of.RP fluid can for making the fluid based on the hydrocarbon antirust fluid of water (or based on) of the surface wettability of inner ring and outer shroud 12,16.Fluid based on hydrocarbon can comprise based on oil fluid (such as, there is the thin oil of kerosene shape denseness) or the non-fluid based on oil (such as, vegetables or vegetables oil, synthetic materials etc.) or water soluble oils or the synthesis rust inhibiting solution based on water.The example being applicable to RP includes but not limited to Quaker FERROCOTE 5856 BF and Quaker FERROCOTE 5856 BF T1.In order to provide antiwear properties to metal-metal surface contact, add at least one additive to RP, to form solution.Examples of such additives can comprise boron compound (such as, boric acid, borate (such as Sodium Tetraborate), boric acid ester, borons acid ester (boronic ester) or hypoborous acid ester (borinic ester)) and extreme pressure (EP) additive (such as, molybdenum dithiophosphate " MoDTP ") at least one.Such as, additive can comprise at least one trialkyl borate, wherein alkyl is any straight or branched alkyl, be similar to but be not limited to (such as, trialkyl borate are as triisopropyl borate ester or tripropoxy-boron) such as ethyl, normal-butyl, isobutyl-, the tertiary butyl, n-pentyl, isopentyl.Do not consider accurate type, antiwear additive is in the solution in RP fluid, so that be assembled into the inner ring 12 of the first shrink-fit and axle 14 one of at least and be assembled into the outer shroud 16 of the second shrink-fit and shell 18 one of at least moistening with RP time, provide fretting wear to protect.In some constructions, inner ring 12 and axle 14 one or both of and outer shroud 16 and shell 18 one or both of are steel, and (namely antiwear additive can have surfactivity for steel, concentrate in contact at steel-steel and experience chemical reaction), to produce shear deformation layer or " low shearing speed regulating course ", make when two surfaces are moved relative to each other, sliding interface is in low shearing speed regulating course.Low shearing speed regulating course discusses in detail in Y. Berthier, M. Godet & M. Brendle (1989): Velocity Accommodation in Friction (speed setting in friction), Tribology Transactions, 32:4,490-496, described document is incorporated herein by reference.Such as, the document describes the difference between simple thick-film lubrication agent in detail, and it acts on by means of only fluid shearing according to predictable principle of hydrodynamics; " do " friction, it is by a lot of more complicated machining function, to adapt to the movement between two articles or surface.In metal to-metal contact, oil film can be there is, but speed setting mechanism does not observe independent simple fluid shearing mechanism." speed setting layer " used herein refers to that the layer of (that is, non-zero speed) ability is moved in the enhancing between two objects or surface therebetween.In some constructions, the boron compound being dissolved in RP fluid can have surfactivity for steel, to produce the speed setting layer of boric acid.MoDTP also has surfactivity for steel as additive, to produce molybdenumdisulphide MoS ₂speed setting layer.Observe in the laboratory of contriver, boron compound (such as, triisopropyl borate ester and tripropoxy-boron) and some EP additives (such as, MoDTP) are used as speed setting layer well in the reciprocating contact kind producing wearing and tearing.Experimental test shows, this method stops fretting wear extremely effectively, and does not sacrifice the inherent corrosion prevention of RP.

By the effect of two kinds of test method determination additives, also illustrate that it uses.The first is Fafnir Fretting Oxidation test (Fei Funa friction oxidation test) (ASTM D-4170-97), and this is the standard test for fretting wear.The second is the vibration conformal wearing test that imitation ring is applied at axle.Although be not restriction, test disclosed herein is carried out to four kinds of different solutions.By mixing (such as, dissolve) one of two kinds of additives as solute (triisopropyl borate ester and 2-ethylhexyl molybdenum dithiophosphate) accounting for cumulative volume 5% and one of two kinds of RP fluids (FERROCOTE 5856 BF T1 and FERROCOTE 5856 BF) as solvent, prepare four kinds of solution.FERROCOTE 5856 BF T1 RP fluid is identical or similar with FERROCOTE 5856 BF, uses solvent cut further.Test at least repeats twice.Fei Funa experimental evidence ASTM method is carried out, and carries out conformal fretting wear test according to following parameter.

Gap: ~ 0.254mm (0.010 inch)

Annular diameters: ~ 49.23mm (1.938 inches)

Outer annular distance: ~ 49.48mm (1.948 inches)

Contact width: ~ 13.07mm (0.515 inch)

Load: ~ 4480N (1000 lbs)

Contact stress: ~ 53MPa (7.7 ksi)

Inner ring surface polishing: ~ μm (μ in)

External annular surface polishing: ~ 0.813 μm (32 μ in)

Oil: 0.1mL FERROCOTE 5856BF, in contact

Vibration: 5 °, at 13.3 Hz

Time length: 22 hours, or when test is by temperature (100 DEG C) or friction

(110lbs) when stopping.

Fei Funa test is the most frequently used does testing of lubricating oil, therefore, improves preparation, to obtain the test conditions close to the actual antirust condition in this field.Make sample ultrasonic cleaning in hexane and Virahol.Surface to inner ring and outer shroud applies the thin layer of FERROCOTE 5856 BF or FERROCOTE 5856 BF and 5% triisopropyl borate ester.It is all excessive to wipe, or makes it drip off (such as, 5 minutes).Once inner ring is fixed on Falex axle, is placed on proving ring top with regard to making the test solution of 0.1mL drip, then fixes outer shroud.Multiple test is carried out to each solution.

Fei Funa experimental measurement is weightless.Weightlessness is larger, and fretting wear is larger.The results are shown in following table.

Table 1

Average weightlessness:	Baseline 5856BF T1	3.475 mg
			5% TIPB /5856BF T1	0.875 mg
	5% MoDTP/5856BF T1	-0.075 mg

Table 2

Average weightlessness:	Baseline 5856BF	1.075 mg
			5% TIPB /5856BF	0.250 mg
	5% MoDTP/5856BF	0.450 mg

Design ASTM D-4170 is to test lubricating oil, and the statistical appraisal in document is correct to lubricating oil.This test is carried out oil antirust agent, instead of to lubricating oil, therefore, we rely on and detect from these statistic data drawn.Utilizing FERROCOTE 5856BF T1 to study the numerical range found to baseline sample is 1.8mg.In FERROCOTE 5856BF tests, the scope of baseline sample is 0.38mg.In two tests, trend is similar, and namely additive reduces fretting wear really.

The result of conformal fretting wear test is the time of testing termination due to friction or temperature.When test conditions reaches friction or temperature cutoff value, protection surface avoids the film destroyed of wearing and tearing.Film continues longer, and it is better to protect.The results are summarized in in following table 3.

The time of table 3 – Falex test Jie Guo – to 65lbs friction cutoff

Owing to being intended to first to be corrosion inhibitor containing (additized) RP solution of additive, therefore, test is containing the rustless property of the RP solution of additive.Also long-term humidity cabinet test is carried out according to ASTM 1748.Be exposed to 120 degree (Fahrenheit temperature) after 4 months in 90% relative humidity, do not show corrosion with the sample that the solution of 5% volume triisopropyl borate ester in Quaker FERROCOTE 5856 T1 applies.Therefore determine that the anti-corrosion capability of antiwear additive to RP fluid itself does not have disadvantageous effect.Other additive, such as MoDTP are slip additive, and due to they uses within the bearing, and thinking does not have disadvantageous effect to the protection against corrosion of RP fluid.

RP fluid containing additive as described herein directly can replace the RP fluid used.In RP solution, the amount of additive can be about or at least about 0.1,0.5,1,2,3,4,5,6,7,8,9 or 10% volume (v/v) with entire volume, and with entire volume about or be less than about 90,80,70,60,50,40,30,20 or 10% volume (v/v), but other amount may also be effective.In some constructions, amount can entire volume between about 1% volume and about 10% volume (v/v), more particularly, in some constructions, can for entire volume about 5% volume (v/v).Although the upper limit need not be had, at very high additive concentration, the rustless property of sacrificing basic RP fluid may be started.In other words, additive can not cause corrosion, but should have the minimum quantity (such as, about or at least about 10,20,30,40,50,60,70,80 or 90%) realizing the necessary basic RP fluid of basic corrosion inhibition function.Any mode of generally applying of RP fluid can apply RP solution containing additive.In some constructions, impregnation section, and make it drain off.Although FERROCOTE 5856BF and FERROCOTE 5856BF T1 provides in this article as an example, but need not have preferential between, those of ordinary skill in the art should be familiar with, and other known RP fluid also can be modified to antiwear additive as herein described.

Another aspect of equal importance is, before installing in the application, may occur false hardening or wearing and tearing between the rolling element and raceway (raceway) of bearing.The RP of resistance to wearing solution as herein described also can reduce the risk of this type wearing and tearing such as occurred between transport and shelf lives.Prevent fretting wear to be also all used in other situation except neck collar shrink-fit and the metal assembly beyond bearing by the additive in RP solution described herein and alleviate fretting wear.The transport of metal parts needs some fretting wear protection form-lubricants usually, as lubricating oil, or physical barriers, as plastics or cardboard.The fretting wear protection provided by the RP of resistance to wearing solution described herein can be enough to be applicable to being used alone, and replaces the fretting wear of these other forms to protect at lower cost.

Claims

1. resistance to wear a rust inhibiting solution, described in the rust inhibiting solution that resistance to wears comprise:

Antirust fluid; With

Be dissolved in the antiwear additive of antirust fluid, described antiwear additive comprises at least one and has surface-active compound for steel, to produce low shearing speed regulating course in metal-metal shrink-fit.

2. the rust inhibiting solution that resistance to wears of claim 1, wherein antirust fluid is the fluid based on hydrocarbon.

3. the rust inhibiting solution that resistance to wears of claim 1, wherein said at least one compound has surfactivity for steel, to produce the low shearing speed regulating course of boric acid.

4. the rust inhibiting solution that resistance to wears of claim 3, wherein said compound comprises at least one in boric acid ester, borons acid ester and hypoborous acid ester.

5. the rust inhibiting solution that resistance to wears of claim 3, wherein said at least one compound comprises trialkyl borate, and wherein alkyl is one of sec.-propyl and n-propyl.

6. the rust inhibiting solution that resistance to wears of claim 1, wherein said at least one compound has surfactivity for steel, to produce the low shearing speed regulating course of molybdenumdisulphide.

7. the rust inhibiting solution that resistance to wears of claim 6, wherein said at least one compound comprises molybdenum dithiophosphate.

8. the rust inhibiting solution that resistance to wears of claim 1, wherein the amount of antiwear additive is at least 0.5% volume and is less than 50% volume.

9. the rust inhibiting solution that resistance to wears of claim 1, wherein the amount of antiwear additive is between about 1% volume and about 10% volume.

10. the rust inhibiting solution that resistance to wears of claim 1, wherein the amount of antiwear additive is about 5% volume.

11. 1 kinds of Bearing assemblies with antiwear properties, described Bearing assembly comprises:

The ring of matable assembly is fixed to by shrink-fit;

The rust inhibiting solution that resistance to wears provided at least shrink-fit, the described rust inhibiting solution that resistance to wears comprises antirust fluid and is dissolved in the antiwear additive of antirust fluid, described antiwear additive comprises at least one and has surface-active compound for steel, to produce low shearing speed regulating course.

The Bearing assembly of 12. claims 11, wherein antirust fluid is the fluid based on hydrocarbon.

The Bearing assembly of 13. claims 11, wherein said at least one compound has surfactivity for steel, to produce the low shearing speed regulating course of boric acid.

The Bearing assembly of 14. claims 13, wherein said at least one compound comprises at least one in boric acid ester, borons acid ester and hypoborous acid ester.

The Bearing assembly of 15. claims 13, wherein said at least one compound comprises trialkyl borate, and wherein alkyl is one of sec.-propyl and n-propyl.

The Bearing assembly of 16. claims 11, wherein said at least one compound has surfactivity for steel, to produce the low shearing speed regulating course of molybdenumdisulphide.

The Bearing assembly of 17. claims 16, wherein said at least one compound comprises molybdenum dithiophosphate.

The Bearing assembly of 18. claims 11, wherein the amount of antiwear additive is at least 0.5% volume and is less than 50% volume.

The Bearing assembly of 19. claims 11, wherein the amount of antiwear additive is between about 1% volume and about 10% volume.

The Bearing assembly of 20. claims 11, wherein the amount of antiwear additive is about 5% volume.

The Bearing assembly of 21. claims 11, wherein said ring is for utilizing matable assembly axle, by the inner ring that shrink-fit is fixing, described shrink-fit is the first shrink-fit, and wherein Bearing assembly comprises the outer shroud be fixed on by the second shrink-fit in shell aperture further, and provides the rust inhibiting solution that resistance to wears further in the second shrink-fit.