[0001] The present invention relates to an anti-galling method for treating materials.
[0002] Two mechanical bodies that slide with respect to each other during their normal operation
can be subject to a phenomenon known as galling.
[0003] The term "galling" normally refers to the occurrence of locking of two or more complementary
moving mechanical members due to excessive sliding friction, which causes the consequent
temporary or permanent interruption of their regular operation.
[0004] Said galling can be due to various reasons, which lead to a single consequence: excessive
overheating of the propulsion unit. For example, galling can be caused by lack of
lubrication, by excessive stress at full power and prolonged over time (caused for
example by an operating rate that is higher than the actual capability of the machine)
or by incorrect play between the parts (an excessively small play between the bushing
and the respective pivot, for example, can cause an interruption of the lubricating
film; an excessive play does not allow correct segregation of the lubricant, if any,
and can generate impacts between the components).
[0005] Between coupled components in reciprocal motion there is generally a lubricant (grease,
oil or specific emulsions), although numerous mechanical couplings in which no lubricant
is used are provided.
[0006] In principle, the present invention relates preferably to any pivot-bushing assembly
the components of which are made of a metallic material (for example steel, aluminum
and alloys of another type) with a reciprocal rotary motion.
[0007] In this type of assemblies, galling often occurs which causes machine downtime and
evident damage of the pivot.
[0008] In order to obviate these drawbacks, lubricants are often interposed between the
pivot and the bushing (within the play between them) and segregated therein by means
of specific sealing elements.
[0009] In some cases, however, the lubricant may not be sufficient to avoid galling, especially
after many hours of operation.
[0010] Accordingly, assemblies of the known type are particularly subject to galling and
in order to avoid its onset periodic maintenance is provided which is aimed at checking
the state of the lubricant arranged in the play between the pivot and the bushing
and at restoring its ideal conditions.
[0011] Therefore, assemblies of the known type are subject to galling phenomena and, if
one wishes to avoid the occurrence of this phenomenon, which would cause machine downtime,
frequent and expensive periodic maintenance of the assemblies is necessary.
[0012] In order to reduce the onset of galling, it is known to resort to the execution of
different types of thermal treatment on pivots made of quenched and tempered steel,
at the end of which the surface of said pivot is subjected to grinding.
[0013] Even after subjecting them to these treatments, the pivots remain in any case subject
to the phenomenon of galling and therefore a long service life of the same cannot
be ensured.
[0015] The aim of the present invention is to solve the problems described above, proposing
an anti-galling method for treating materials that allows minimizing the onset of
galling to the point of making it even negligible.
[0016] Within the scope of this aim, an object of the invention is to propose an anti-galling
method for treating materials that makes it possible to minimize the risk of galling
of a pivot intended to be turned with respect to a bushing that is mated with it.
[0017] Another object of the invention is to propose an anti-galling method for treating
materials that ensures a reduction of the periodic maintenance of the mechanical couplings
that comprise components subjected to said method.
[0018] Another object of the present invention is to provide an anti-galling method for
treating materials that has low costs, is relatively simple to provide in practice
and is safe in application.
[0019] This aim and these and other objects that will become more apparent hereinafter are
achieved by an anti-galling method for treating materials, which provides for subjecting
at least one of the at least two components mutually coupled with at least one degree
of freedom, made of metallic material, to a first preliminary step of thermal treatments
to increase surface hardness and to a second preliminary step of surface grinding,
which consists in
- performing a first step of washing at least one portion of the surface of the at least
one component subjected previously to the preliminary steps;
- performing a second step of shot peening said at least one portion of the surface
of the at least one component previously subjected to washing;
- performing a third step of applying a layer of molybdenum disulfide on said at least
one portion of the at least one component previously subjected to shot peening.
[0020] Further characteristics and advantages of the invention will become more apparent
from the description of a preferred but not exclusive embodiment, of the anti-galling
method for treating materials according to the invention, illustrated by way of non-limiting
example in the accompanying drawing, wherein Figure 1 is a sectional front view, along
a transverse plane, of a possible rotatable mechanical coupling provided by applying
the anti-galling method according to the invention.
[0021] With particular reference to the figure, the numeral 1 generally designates a possible
rotary mechanical coupling provided by applying the anti-galling method for treating
materials according to the invention.
[0022] The method according to the invention can be applied to mechanical couplings between
which there is at least one degree of freedom.
[0023] Said components are preferably made of metallic material: by way of example, mention
is made of metallic alloys, such as steel, or metals substantially in the pure state,
such as aluminum. If reference is made to components made of steel, quenched and tempered
steel will generally be used.
[0024] The anti-galling method according to the invention entails subjecting at least one
of the at least two components to a first preliminary step of thermal treatments to
increase surface hardness and to a second preliminary step of surface grinding.
[0025] The two preliminary steps are the ones normally applied in the background art.
[0026] The method according to the invention provides for the execution of additional consecutive
steps on the at least one component.
[0027] It is in fact necessary to perform a first step of washing at least one portion of
the surface of the at least one component previously subjected to the preliminary
steps.
[0028] It is then necessary to perform a second step of shot peening of at least one portion
of the surface of the at least one component previously subjected to washing.
[0029] Finally, the process requires the execution of a third step of application of a layer
of molybdenum disulfide on the at least one portion of the at least one component
previously subjected to shot peening.
[0030] The first washing step also comprises a surface degreasing of the at least one portion
of the surface of the at least one component previously subjected to the preliminary
steps.
[0031] Degreasing consists in removing any trace of grease or dirt from the surface of the
component (generally made of steel) before subjecting it to subsequent treatments
(mechanical, thermal, etcetera) or to surface finishing. It is important to remove
traces of grease and dirt, because the presence of organic molecules, being constituted
essentially by carbon, can be dangerous: the carbon may in fact enter the matrix of
the material during a thermal treatment, if performed (some mechanical treatments
that generate heat also can cause the migration of the carbon contained in the grease
that is present on the external surface of the part being machined), causing an aesthetic
damage to the part and most of all a local degradation of its characteristics. Carbon
enrichment can affect negatively the mechanical properties of the part by hardening
and embrittlement, even reducing its corrosion resistance.
[0032] Degreasing can be performed with organic solvents by utilizing the chemical principle
according to which "like dissolves like" or with alkaline or acid solvents in an aqueous
base. In this second case, one acts on the hydrophilic part of the compound.
[0033] The second step of shot peening the at least one portion of the surface of the at
least one component previously subjected to washing is extended to obtain, in said
at least one portion, a state of residual compression with a value comprised between
200 MPa and 10000 MPa: the ideal value of residual compression that can be obtained
for correct execution of the method according to the invention is approximately 1100
MPa.
[0034] Shot peening is an operation that consists in surface cold hammering by means of
a violent jet of spherical shot, or of cylindrical shot obtained by cutting a wire
(known as cut-wire shot).
[0035] The machines that perform this treatment, i.e., peening machines, propel the jet
of rounded or cylindrical shot toward the parts to be machined by means of one or
more rapidly rotating impellers, generally centrifugal ones, or by means of compressed
air; in any case, the materials used for the grit can be cast iron, steel, glass and,
more rarely, ceramics.
[0036] Moreover, shot peening improves the distribution of the surface tensions that has
been perturbed by mechanical treatments and/or thermal treatments and attenuates the
concentrations of efforts produced by notches, threads, decarburization, etcetera.
[0037] Shot peening, as regards the manners of execution, resembles sanding, while for its
intended purpose it is more similar to rolling, since it acts more on plasticity than
on abrasion.
[0038] It causes in fact a surface compression, since its jet induces a plastic deformation
that propagates to a depth of a few tenths of a millimeter in the material being considered
and technically it serves to improve the distribution of surface tensions, increasing
the fatigue strength of the treated part.
[0039] This effect is due to the residual compressive tensions that it causes in the surface
of the material and in the underlying layers, which are able to reduce the internal
tensions when the part is subjected to stresses. The material is thus rendered more
resistant to fatigue stresses.
[0040] At the end of the treatment, due to the micro-cavities that are generated and are
mutually superimposed, one has, as a secondary effect, also a reduction in the quantity
of light reflected on the material, i.e., a sort of satin finish.
[0041] The effect of shot peening depends, if the nature of the shot peened material remains
constant, on the hardness and size of the shot, on the flowrate, on the velocity and
angle of impingement of the stream, on the distance of the part from the projection
system, on the intensity and on the coverage. Shot peening intensity, measured in
Almen degrees, is evaluated by the curvature undergone, in the direction of incidence
of the stream, by one of the two faces of a laminar test piece (76 x 19 mm) obtained
from C 70 UNI 7845 killed steel hardened and tempered at 44 ÷ 45 HRC, the thickness
"s" of which can assume three different values that correspond to shot peenings of
weak intensity N, medium intensity A, and strong intensity C. The curvature, produced
by the stream of shot, is measured with a quadrant comparator.
[0042] Coverage is determined by subjecting a polished test piece to a stream of shot for
a time that corresponds to the associated intensity and by measuring, with a 50X magnification,
the areas of all the impinged regions located within a circumference having a conventionally
set diameter; coverage is defined as the ratio between the sum of the areas of the
impinged regions and the area of the circle.
[0043] This second step of shot peening of the at least one portion of the surface of the
at least one component subjected previously to washing is performed with S110 steel
balls with a diameter comprised between 0.01 mm and 1.5 mm: preferably, balls are
adopted which have a diameter equal to approximately 0.3 mm, a value for which an
optimum result of the treatment in the method according to the invention has been
observed.
[0044] It should also be noted that the second step of shot peening of the at least one
portion of the surface of the at least one component subjected previously to washing
is performed with an intensity between 4 and 40 Almen degrees referred to a type A
test piece (i.e., peening of medium intensity identified by the letter A).
[0045] In this case also, it is deemed appropriate to specify that the ideal value of peening
intensity, expressed in Almen degrees and referred to peening of medium intensity
identified by the letter A, is approximately 6 or 8.
[0046] In any case, said second step of shot peening is performed by providing a coverage
of more than 60%, although optimum results are achieved with 100% coverage of said
at least one portion.
[0047] The third step of the method according to the invention, which corresponds to the
application of a layer of molybdenum disulfide on the at least one portion of the
at least one component, entails the provision of a layer with a thickness comprised
between 1 and 50 µm.
[0048] In this case also, it is convenient to specify that ideal thicknesses of molybdenum
disulfide, within the scope of the method according to the invention, are between
5 and 15 µm.
[0049] The third step of application of a layer of molybdenum disulfide on the at least
one portion of the at least one component provides for the aspersion, on said portion,
of an aerosol comprising molybdenum disulfide in a percentage by weight of more than
10%, inorganic resins, solvents and propellants.
[0050] It is preferable to adopt aerosols in which the molybdenum disulfide percentage is
higher than 20% in order to obtain better results and a more efficient and stable
layer on the treated portion of the component.
[0051] The combination of the steps indicated and provided by the method according to the
invention is particularly effective, since surface cleaning defines ideal conditions
for the adhesion of the molybdenum disulfide layer.
[0052] At the same time, the shot peening step generates on the outer surface of the component
a plurality of contiguous micro-concavities.
[0053] This surface irregularity facilitates the adhesion of the molybdenum disulfide, ensuring
that deposits of even higher thickness are produced locally which increase its structural
strength.
[0054] Furthermore, it is evident that with respect to a same smooth surface, the surface
affected by a plurality of contiguous concavities without discontinuity has a larger
area, thus extending the regions of contact between the molybdenum disulfide and the
surface itself: the toughness of the adhesion of the molybdenum disulfide is directly
proportional to the area of the surface that is coated and therefore an irregular
surface produces a higher stability of the stratification.
[0055] Finally, the residual tension produced by the shot peening step ensures higher rigidity
of the surface of the component.
[0056] A component that is less subject to deformations is certainly more suitable to be
subjected subsequently to the deposition of a layer of rigid material, since deformations
might cause layer separations.
[0057] The combination of the steps entails therefore an overlap of the indicated effects
and also a synergistic combination thereof which ensures a strength of the layer of
molybdenum disulfide and also an effectiveness of the mechanical coupling that is
surprising in terms of durability and mechanical performance.
[0058] It should be noted that the method according to the invention also provides for the
optional execution of an additional auxiliary step of removing material in the other
of the two mutually coupled components, in order to increase play between them.
[0059] The removal of material, in this case, occurs at at least one region of the other
component that does not face and is proximate to the at least one portion subjected
to the first to third steps.
[0060] The removal of material makes it possible to ensure that sliding between the two
(or more) components occurs exclusively at the portions subjected to the method: the
other parts in fact are separated by considerable play, which is obtained with the
further removal of material provided in the auxiliary step cited earlier.
[0061] Moreover, the increase in plays makes it possible to contain a larger quantity of
lubricant (oil or grease) within said plays. The lubricant is segregated within the
free space (play) that is present between the components by means of respective sealing
elements of the traditional type, for which the provision of any specific description
is not deemed necessary (since they are known).
[0062] According to a particular application of the method according to the invention, which
makes it possible to simply and immediately identify its numerous advantages and considerable
potentials, a first component is constituted by a pivot 2 and a second component is
constituted by a bushing 3.
[0063] The pivot 2, in the configuration for use, is inserted rotatably within the bushing
3 and defines a sliding of its at least one portion 4, subjected to the first to third
steps, on corresponding areas of the internal surface of the bushing 3.
[0064] In turn, the bushing 3 is machined with removal of material on a part of its internal
surface in order to define a region 5 of the cavity formed by it that has a larger
diameter.
[0065] In this manner it is possible to identify a play 6 (which can also have considerable
dimensions) between the pivot 2 and said region 5 of the bushing 3.
[0066] Within the play 6, a predefined quantity of lubricant can be segregated which facilitates
the mutual rotations of the pivot 2 and the bushing 3.
[0067] The accompanying figure, in particular, refers to a possible coupling of links of
a chain that are mutually articulated.
[0068] Analyzing specifically the constructive solution given by way of example, the links
7 and 8 of the chain in this case are keyed on the bushing 3 with a predefined interference.
[0069] Likewise, two other chain links 9 and 10, opposite the ones that are integral with
the bushing 3, are keyed, again by adopting a predefined interference, on the pivot
2.
[0070] In practice, according to the configuration defined previously, the assembly of the
pivot 2 and of the links 9 and 10 constitutes a first joint part and the assembly
of the bushing 3 and of the links 7 and 8 constitutes a second joint part.
[0071] The two joint parts constitute the mechanical coupling, which can be particularly
efficient if the portions 4 of the pivot 2 that are intended to slide on the internal
surface of the bushing 3 have been subjected to the method according to the invention.
[0072] Finally, it is specified that in order to ensure the necessary segregation of the
lubricant in the play 6 defined between the pivot 2 and the region with larger diameter
of the cavity inside the bushing 3, sealing elements 11 and 12 are used between the
pivot 2 and the bushing 3.
[0073] Chains of the type shown in the accompanying figure are used universally in earth-moving
machines and in many other industrial processes.
[0074] The method according to the invention can be applied in any case to a considerable
number of other mechanical couplings and joints which, due to the mechanical tensions
applied and/or to the speed and frequency of the mutual movements, are normally subject
to galling.
[0075] Advantageously, the present invention solves the problems described earlier, proposing
an anti-galling method for treating materials that allows minimizing the onset of
galling to the point of even rendering it negligible.
[0076] This result is achieved by the synergistic effect of the residual state of compression
induced by the shot peening step and by the presence of a layer of molybdenum disulfide.
[0077] Usefully, the anti-galling method according to the invention allows minimizing the
risk of galling of a pivot 2 intended to be turned with respect to a bushing 3 that
is mated therewith, thus being particularly effective in the case of rotary couplings.
[0078] Efficiently, the anti-galling method according to the invention ensures a reduction
in periodic maintenance of the mechanical couplings comprising components subjected
to said method.
[0079] In fact, the reduced onset of the galling phenomenon and the presence of a greater
play 6 (with respect to couplings of the traditional type) ensures a drastic reduction
of the number of required maintenance interventions.
[0080] Favorably, the anti-galling method according to the invention can be performed with
substantially low costs, is relatively simple to provide in practice and is safe in
application.
[0081] The materials used, as well as the dimensions, may be any according to the requirements
and the state of the art.
[0082] Where technical features mentioned in any claim are followed by reference signs,
those reference signs have been included for the sole purpose of increasing the intelligibility
of the claims and accordingly such reference signs do not have any limiting effect
on the interpretation of each element identified by way of example by such reference
signs.
1. An anti-galling method for treating materials, which provides for subjecting at least
one of the at least two components mutually coupled with at least one degree of freedom,
made of metallic material, to a first preliminary step of thermal treatments to increase
surface hardness and to a second preliminary step of surface grinding, which consists
in
- performing a first step of washing at least one portion of the surface of the at
least one component subjected previously to the preliminary steps, said first washing
step also comprising surface degreasing of the at least one portion of the surface
of the at least one component subjected previously to the preliminary steps;
- performing a second step of shot peening said at least one portion of the surface
of the at least one component previously subjected to washing;
- performing a third step of applying a layer of molybdenum disulfide to said at least
one portion of the at least one component previously subjected to shot peening; said
third step of application of a layer of molybdenum disulfide on said at least one
portion of the at least one component providing for the aspersion, on said at least
one portion, of an aerosol comprising molybdenum disulfide in a percentage by weight
of more than 10%, inorganic resins, solvents and propellants.
2. The anti-galling method according to claim 1, characterized in that said second step of shot peening said at least one portion of the surface of the
at least one component previously subjected to washing is prolonged until a state
of residual compression with a value comprised between 200 MPa and 10000 MPa is obtained
in said at least one portion.
3. The anti-galling method according to claim 1, characterized in that said second step of shot peening said at least one portion of the surface of the
at least one component previously subjected to washing is performed with S110 steel
balls with a diameter comprised between 0.01 mm and 1.5 mm.
4. The anti-galling method according to claim 1, characterized in that said second step of shot peening said at least one portion of the surface of the
at least one component previously subjected to washing is performed with an intensity
whose value is comprised between 4 and 20 Almen degrees referred to a type A test
piece.
5. The anti-galling method according to claim 1, characterized in that said second step of shot peening said at least one portion of the surface of the
at least one component previously subjected to washing is performed with a coverage
of more than 60% of said at least one portion.
6. The anti-galling method according to claim 1, characterized in that said third step of application of a layer of molybdenum disulfide on said at least
one portion of the least one component provides for the creation of a layer with a
thickness comprised between 1 and 50 µm.
7. The anti-galling method according to claim 1, characterized in that it comprises an auxiliary step of removing material in the other one of the two mutually
coupled components to increase the play between them, said removal of material taking
place in at least one region of said other component that does not face and lie proximate
to said at least one portion subjected to the first to third steps.
8. The anti-galling method according to claim 1, characterized in that a first component is a pivot (2) and a second component is a bushing (3), said pivot
(2), in the configuration for use, being inserted rotatably within said bushing (3)
and defining a sliding of its at least one portion (4), subjected to the first to
third steps, on corresponding areas of the internal surface of said bushing (3).
1. Verfahren zur Verhinderung von Fressen zur Behandlung von Materialien, das vorsieht,
dass mindestens eines der mindestens zwei mit mindestens einem Freiheitsgrad miteinander
gekoppelten Bauteile aus metallischem Material einem ersten vorbereitenden Schritt
von Wärmebehandlungen zur Erhöhung der Oberflächenhärte und einem zweiten vorbereitenden
Schritt des Oberflächenschleifens unterzogen wird, der besteht in
- Durchführen eines ersten Schritts des Waschens mindestens eines Abschnitts der Oberfläche
des mindestens einen Bauteils, das zuvor den vorbereitenden Schritten unterzogen wurde,
wobei der erste Schritt des Waschens auch das Entfetten der Oberfläche des mindestens
einen Abschnitts der Oberfläche des mindestens einen Bauteils umfasst, das zuvor den
vorbereitenden Schritten unterzogen wurde;
- Durchführen eines zweiten Schritts des Kugelstrahlens des mindestens einen Abschnitts
der Oberfläche des mindestens einen Bauteils, das zuvor dem Waschen unterzogen wurde;
- Durchführen eines dritten Schritts des Aufbringens einer Schicht aus Molybdändisulfid
auf den mindestens einen Abschnitt des mindestens einen Bauteils, das zuvor dem Kugelstrahlen
unterzogen wurde; wobei der dritte Schritt des Aufbringens einer Schicht aus Molybdändisulfid
auf den mindestens einen Abschnitt des mindestens einen Bauteils das Aufsprühen eines
Aerosols auf den mindestens einen Abschnitt vorsieht, das Molybdändisulfid in einem
Gewichtsprozentanteil von mehr als 10 %, anorganische Harze, Lösungsmittel und Treibmittel
umfasst.
2. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass der zweite Schritt des Kugelstrahlens des mindestens einen Abschnitts der Oberfläche
des mindestens einen Bauteils, das zuvor dem Waschen unterzogen wurde, verlängert
wird, bis ein Zustand der Restkompression mit einem Wert zwischen 200 MPa und 10000
MPa in dem mindestens einen Abschnitt erreicht wird.
3. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass der zweite Schritt des Kugelstrahlens des mindestens einen Abschnitts der Oberfläche
des mindestens einen Bauteils, das zuvor dem Waschen unterzogen wurde, mit S110-Stahlkugeln
mit einem Durchmesser zwischen 0,01 mm und 1,5 mm durchgeführt wird.
4. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass der zweite Schritt des Kugelstrahlens des mindestens einen Abschnitts der Oberfläche
des mindestens einen Bauteils, das zuvor dem Waschen unterzogen wurde, mit einer Intensität
durchgeführt wird, deren Wert zwischen 4 und 20 Almen-Grad liegt, bezogen auf ein
Prüfstück vom Typ A.
5. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass der zweite Schritt des Kugelstrahlens des mindestens einen Abschnitts der Oberfläche
des mindestens einen Bauteils, das zuvor dem Waschen unterzogen wurde, mit einer Bedeckung
von mehr als 60 % des mindestens einen Abschnitts durchgeführt wird.
6. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass der dritte Schritt des Auftragens einer Schicht aus Molybdändisulfid auf den mindestens
einen Abschnitt des mindestens einen Bauteils für die Erzeugung einer Schicht mit
einer Dicke zwischen 1 und 50 µm sorgt.
7. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass es einen zusätzlichen Schritt des Abtragens von Material in dem anderen der beiden
miteinander gekoppelten Bauteile umfasst, um das Spiel zwischen ihnen zu vergrößern,
wobei das Abtragen von Material in mindestens einem Bereich des anderen Bauteils erfolgt,
der dem mindestens einen Abschnitt, der den ersten bis dritten Schritten unterzogen
wurde, nicht zugewandt ist und in der Nähe davon liegt.
8. Verfahren zur Verhinderung von Fressen nach Anspruch 1, dadurch gekennzeichnet, dass ein erstes Bauteil ein Drehzapfen (2) und ein zweites Bauteil eine Buchse (3) ist,
wobei der Drehzapfen (2) in der Gebrauchskonfiguration drehbar in die Buchse (3) eingesetzt
ist und ein Gleiten seines mindestens einen Abschnitts (4), der den ersten bis dritten
Schritten unterzogen wurde, auf entsprechenden Bereichen der Innenfläche der Buchse
(3) definiert.
1. Procédé d'anti-grippage pour le traitement de matériaux, qui prévoit de soumettre
au moins l'un des au moins deux composants mutuellement couplés selon au moins un
degré de liberté, réalisés en un matériau métallique, à une première étape préliminaire
de traitements thermiques pour augmenter la dureté de surface et à une seconde étape
préliminaire de meulage de surface, qui consiste à
- effectuer une première étape de lavage d'au moins une partie de la surface de l'au
moins un composant soumis précédemment aux étapes préliminaires, ladite première étape
de lavage comprenant également un dégraissage de surface de l'au moins une partie
de la surface de l'au moins un composant soumis précédemment aux étapes préliminaires
;
- effectuer une deuxième étape de grenaillage de ladite au moins une partie de la
surface de l'au moins un composant précédemment soumis au lavage ;
- effectuer une troisième étape d'application d'une couche de disulfure de molybdène
sur ladite au moins une partie de l'au moins un composant précédemment soumis à un
grenaillage ; ladite troisième étape d'application d'une couche de disulfure de molybdène
sur ladite au moins une partie de l'au moins un composant prévoyant l'aspersion, sur
ladite au moins une partie, d'un aérosol comprenant du disulfure de molybdène selon
un pourcentage en poids de plus de 10 %, des résines inorganiques, des solvants et
des propulseurs.
2. Procédé d'anti-grippage selon la revendication 1, caractérisé en ce que ladite deuxième étape de grenaillage de ladite au moins une partie de la surface
de l'au moins un composant précédemment soumis à un lavage est prolongée jusqu'à ce
qu'un état de compression résiduelle avec une valeur comprise entre 200 MPa et 10000
MPa soit obtenu dans ladite au moins une partie.
3. Procédé d'anti-grippage selon la revendication 1, caractérisé en ce que ladite deuxième étape de grenaillage de ladite au moins une partie de la surface
de l'au moins un composant précédemment soumis à un lavage est effectuée avec des
billes d'acier S110 d'un diamètre compris entre 0,01 mm et 1,5 mm.
4. Procédé d'anti-grippage selon la revendication 1, caractérisé en ce que ladite deuxième étape de grenaillage de ladite au moins une partie de la surface
de l'au moins un composant précédemment soumis à un lavage est effectuée avec une
intensité dont la valeur est comprise entre 4 et 20 degrés Almen par rapport à une
éprouvette de type A.
5. Procédé d'anti-grippage selon la revendication 1, caractérisé en ce que ladite deuxième étape de grenaillage de ladite au moins une partie de la surface
de l'au moins un composant précédemment soumis à un lavage est effectuée avec une
couverture de plus de 60 % de ladite au moins une partie.
6. Procédé anti-grippage selon la revendication 1, caractérisé en ce que ladite troisième étape d'application d'une couche de disulfure de molybdène sur ladite
au moins une partie de l'au moins un composant permet la création d'une couche avec
une épaisseur comprise entre 1 µm et 50 µm.
7. Procédé anti-grippage selon la revendication 1, caractérisé en ce qu'il comprend une étape auxiliaire d'enlèvement de matière dans l'autre des deux composants
mutuellement couplés pour augmenter le jeu entre eux, ledit enlèvement de matière
ayant lieu dans au moins une région dudit autre composant qui ne fait pas face et
ne se trouve pas à proximité de ladite au moins une partie soumise aux première à
troisième étapes.
8. Procédé anti-grippage selon la revendication 1, caractérisé en ce qu'un premier composant est un pivot (2) et un second composant est une douille (3),
ledit pivot (2), dans la configuration d'utilisation, étant inséré de manière rotative
dans ladite douille (3) et définissant un glissement de son au moins une partie (4),
soumise aux première à troisième étapes, sur des zones correspondantes de la surface
interne de ladite douille (3).