Initial failure indicator for sub-surface lower layer of wear component

Abstract

The wear component comprises a subsurface lower layer initial failure indicator; the mechanical component includes at least one wear component comprising a subsurface sublayer initial failure indicator; and the mechanical system comprises at least one mechanical component, the at least one mechanical component comprises at least one wear component, and the at least one wear component comprises a subsurface sublayer initial failure indicator. An elastomeric seal (300) has one or more failure indicators that include elements and / or molecules that are spectrally distinguishable from operating intrinsic component species of a mechanical system and are located below the elastomeric seal at one or more subsurface distances, the one or more subsurface distances include at least one subsurface distance within an initial failure region (302). The frictional wear of the elastomeric seal (300) may expose a sub-surface layer (304) with a failure indicator embedded therein, each exposure causing spectrally distinguishable elements and / or molecules to mix with a lubricant of the mechanical system. Based on detecting the failure indication characteristic spectrum, the mechanical system may be removed from operation and one or more elastomeric seals (300) replaced.

Description

Technical Field

[0001] The present disclosure relates to wear components of mechanical systems. More particularly, the present disclosure relates to wear components comprising a subsurface incipient failure indicator. Background Art

[0002] Routine wear of mechanical components during operation of mechanical systems is a major source of expense to operators of such mechanical systems. Among the most common causes of wear, frictional wear occurs in mechanical systems when a hard surface slides against another surface, thereby removing material from the other surface. Additionally, fatigue occurs in mechanical systems when a material is subjected to cyclic loading (i.e., repeated loading forces) that causes cracks to form in the material at or beneath its surface. During the operational life of a mechanical system, some components that are subject to severe wear damage will cause the system's performance to degrade, and such components may be replaced to restore the system to its previous performance without having to replace the entire system. Such replaceable components that are subject to wear may be collectively referred to as "wear parts" or "wear components."

[0003] Various forms of wear cause the performance of mechanical systems and their wear components to gradually experience incipient failure rather than catastrophic failure. Because incipient failures are gradual and may not cause noticeable performance degradation for a period of time, operators of mechanical systems containing wear components that experience incipient failure due to wear may continue to operate these systems normally without detecting the occurrence of wear until the wear worsens and causes catastrophic failure.

[0004] Therefore, if operators of mechanical systems fail to detect incipient wear failures in a timely manner, they risk not being able to prevent catastrophic failures. Because the worn components are often located at the mechanical seals of the system, operators cannot easily access the worn components for visual inspection. Various spectroscopic oil analysis techniques have been developed to measure mechanical wear indirectly: by sampling the fluid collected from the lubricated machinery, the elements and molecules present in the sample can be identified to determine the extent of metal debris generated by wear.

[0005] However, while oil analysis is often used to detect wear of metallic components, non-metallic components, such as elastomers used in mechanical seals, are also subject to mechanical wear. Incipient failure of mechanical seals due to wear can also lead to gradual failure of the mechanical system. Therefore, there is a need to detect any mechanical wear (including elastomer wear) during the incipient failure period without relying on complete failure of the mechanical system as a warning sign.

[0006] U.S. Patent No. 6,752,604 (the "'604 Patent") describes encapsulating a tracer material in the vanes of a sliding vane pump and detecting vane wear by detecting the emission of the tracer material when the vanes reach a worn state. However, such tracer materials require non-traditional detection techniques, such as the use of magnets to collect the tracer material. Such non-traditional wear detection techniques described in the '604 Patent add unnecessary complexity to the routine operation and maintenance of the mechanical system and serve no purpose other than detecting a single tracer material.

[0007] Example embodiments of the present disclosure are intended to overcome the above-mentioned drawbacks. Summary of the invention

[0008] In an example of the present disclosure, an elastomeric member includes: an exterior face; a first subsurface layer located below at least a portion of the exterior face; and a first incipient failure indicator embedded through the first subsurface layer. The first incipient failure indicator includes an element or molecule that is spectrally distinguishable from a substance that is an intrinsic component of the operation of a mechanical system.

[0009] In another example of the present disclosure, an actuator includes: a barrel; a piston member; a rod member; a first elastomeric seal, the first elastomeric seal being assembled into a circumferential first gland of the piston member adjacent to the barrel; and a second elastomeric seal, the second elastomeric seal being assembled into a circumferential second gland of the barrel adjacent to the rod. The first elastomeric seal has a first subsurface layer having a first incipient failure indicator embedded through the first subsurface layer. The second elastomeric seal has a second subsurface layer having a second incipient failure indicator embedded through the second subsurface layer.

[0010] In yet another example of the present disclosure, a system includes a first hydraulic actuator and a second hydraulic actuator. The first hydraulic actuator has a first elastomeric seal that is assembled into a circumferential first gland of the first hydraulic actuator; the second hydraulic actuator has a second elastomeric seal that is assembled into a circumferential second gland of the second hydraulic actuator. The first elastomeric seal has a first subsurface layer that has a first incipient failure indicator embedded through the first subsurface layer. The second elastomeric seal has a second subsurface layer that has a second incipient failure indicator embedded through the second subsurface layer. The first incipient failure indicator and the second incipient failure indicator each include an element or molecule that is spectrally distinguishable from a substance that is an intrinsic component of the operation of the mechanical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1A cross-sectional view of a hydraulic cylinder is illustrated.

[0012] Figure 2 A cross-sectional view of an elastomeric seal including an incipient failure region is illustrated.

[0013] Figure 3 A cross-sectional view of an elastomeric seal including an incipient failure region and a subsurface failure indicator is illustrated.

[0014] Figure 4 Illustrated Figure 1 A hydraulic cylinder is provided with an elastomeric seal providing a dynamic seal.

[0015] Figure 5 An example computing system for implementing spectral analysis techniques as described herein is illustrated.

[0016] Specific method

[0017] Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

[0018] Figure 1 Illustrated is a cross-sectional view of a hydraulic cylinder 100. By way of example, in a conventional hydraulic cylinder, a hydraulic fluid chamber 102 (shown in phantom) is housed within a cylinder barrel 104, and the fluid chamber 102 is enclosed by the alignment of a rod 106 and a piston 108 within the cylinder barrel 104.

[0019] The work performed by many mechanical systems, such as stationary machine tools and mobile construction and agricultural machinery, is driven by hydraulic actuator assemblies, such as hydraulic cylinders 100, as shown in FIG. Figure 1 exemplified.

[0020] The piston 108 further divides the fluid chamber 102 into two partitions 102A and 102B, one partition being located in either direction of the actuation motion of the piston 108. Actuation of such a hydraulic actuator is powered by a pressurized working fluid that is pumped through the fluid chamber enclosed by the cylinder barrel 104 and divided by the piston 108. Powered actuation of the hydraulic cylinder 100 requires that the working fluid does not mix between the two chamber partitions 102A and 102B and that the working fluid does not leak from the entire fluid chamber 102.

[0021] The rod and piston assembly does not cooperate with the cylinder 104, but is actuated through an opening in the cylinder 104 (hereinafter illustrated as opening 110). Likewise, the piston 108 is actuated through the fluid chamber 102. Such actuation leaves a path for fluid leakage, and in order to allow actuation, such a path cannot be statically sealed. Therefore, mechanical seals in hydraulic actuator assemblies are usually installed to perform dynamic sealing, in which the seal deforms under the pressure of the fluid to block the outward passage of the fluid in the direction of the pressure.

[0022] In a common hydraulic cylinder, a mechanical seal is established by a combination of a gland and an elastomeric member such as an O-ring. Where two surfaces are adjacent, the gland is formed as a groove around the periphery of one of the two surfaces, wherein a plurality of glands may be formed around a plurality of peripheries of one of the two surfaces. For each gland, an elastomeric seal or a wear ring is fitted into the gland, and each of the elastomeric seal and the wear ring is a wear component that is subject to significant wear during operation of the hydraulic cylinder.

[0023] If at least one of the two adjacent surfaces is not stationary relative to each other during operation of the hydraulic cylinder in the mechanical system, the elastomeric seal can be freely assembled into the gland without being statically attached. In addition, the wear ring to be described later can be assembled into the other gland without being statically attached. Conversely, if both adjacent surfaces are stationary relative to each other during operation of the hydraulic cylinder in the mechanical system, the elastomeric seal can be attached in the gland relative to both adjacent surfaces.

[0024] Typically, an elastomeric seal may be a circular component manufactured by molding an elastomeric compound. The elastomeric compound may consist of a combination of polymers and other auxiliaries and / or additives that is cured by a process such as vulcanization, resulting in the polymers forming crosslinks, creating a non-plastic state, wherein the elastomeric compound acquires elastic properties, allowing it to recover its original shape after deformation. The curing of the elastomeric compound constituting the elastomeric seal is typically performed simultaneously with the shaping of the elastomeric seal in the molding process.

[0025] In contrast, wear rings can be circular rings manufactured by molding a variety of possible materials, including metals, thermosetting elastomeric compounds, and thermoplastic compounds that do not have elastic properties. Wear rings between two adjacent surfaces do not seal, but rather guide the movement of one surface against another and control the level of friction between the two surfaces.

[0026] By way of example, Figure 1As illustrated, the cylinder 104 includes glands 112A, 114A, 116A, and 118A from outside to inside on the surface adjacent to the rod 106. In addition, the piston 108 includes glands 120A and 122A on the surface adjacent to the cylinder 104. Additionally, between the two inner surfaces, the cylinder 104 includes a gland 124A on one of the two inner surfaces. Additionally, the piston 108 includes a gland 126A on the surface adjacent to the inner section of the rod 106.

[0027] An elastomeric seal 112B is disposed within the gland 112A. The gland 112A is open to the outside, and the elastomeric seal 112B extends outwardly from the gland 112B above the rod 106. The elastomeric seal 112B may be a dust seal configured to seal the interior of the cylinder 104 to prevent entry of foreign matter such as contaminants.

[0028] In each of the glands 114A, 118A and 120A, a corresponding elastomeric seal 114B, 118B and 120B is provided. Each of the elastomeric seals is confined within its corresponding gland by a surface adjacent to the side of the corresponding gland, which encloses the gland. Each of the elastomeric seals is free to move within its corresponding gland, providing a dynamic seal.

[0029] In each of the glands 116A and 122A, a corresponding guide ring 116B and 122B is provided. Each of the guide rings is defined in its corresponding gland by a surface adjacent to the side of the corresponding gland, which encloses the gland. Each of the guide rings can rotate circumferentially in its corresponding gland relative to the two adjacent surfaces.

[0030] With each of the glands 124A and 126A, a respective elastomeric seal 124B and 126B is provided. Each of the elastomeric seals is statically disposed between two adjacent surfaces stationary relative to one another (the interior surface of the cylinder 104 in the case of the gland 124A, and the interior surfaces of the piston 108 and the rod 106 in the case of the gland 126A), providing a static seal rather than a dynamic seal.

[0031] Thus, elastomeric seal 112B prevents foreign matter from entering cylinder barrel 104; elastomeric seals 114B and 118B collectively prevent pressurized working fluid in chamber partition 102A from leaking from cylinder barrel 104, with one seal acting as a buffer for the other seal; and elastomeric seal 120B prevents pressurized working fluid in chamber partition 102A or chamber partition 102B from leaking into the other chamber partition. Typically, leakage of working fluid will cause hydraulic cylinder 100 to depressurize, thereby hampering the operating performance of the hydraulic cylinder and any mechanical system that includes the hydraulic cylinder.

[0032] In such examples of elastomeric seals, those elastomeric seals configured to perform dynamic sealing are subject to abrasive wear due to the repeated contact of the elastomeric seal with one or more adjacent surfaces. Those elastomeric seals configured to perform dynamic sealing may also be subject to biting, cracking, spiral failure or other failure modes that may develop in an incipient manner before turning into a catastrophic failure.

[0033] Because the moving components of a mechanical system are lubricated before and during operation, oil analysis techniques have been developed in which samples of lubricant from the mechanical system during operation (hereinafter referred to as "operational lubricant" for brevity) are collected over time for predictive maintenance purposes. When two surfaces are adjacent in a mechanical system and at least one of the surfaces moves relative to the other during operation of the mechanical system, lubricant is applied to at least one of the two surfaces to reduce friction between the two surfaces during operation of the mechanical system.

[0034] During the operation of a mechanical system, various elemental substances and / or molecular substances may enter the running lubricant in the mechanical system, and the presence of such elemental substances and / or molecular substances may be detected in a running lubricant sample by spectroscopic oil analysis ("SOA"), which generally refers to various techniques for determining elemental composition based on spectroscopic analysis of a running lubricant sample, such as atomic absorption spectroscopy ("AAS") and inductively coupled plasma spectroscopy ("ICP"), and various techniques for determining molecular composition based on spectroscopic analysis of a running lubricant sample, such as Fourier transform infrared ("FTIR") spectroscopy, and the like.

[0035] Oil analysis techniques detect wear debris from metallic wear components (hereinafter referred to as "wear metals" for brevity) based on the corresponding composition of the mechanical system components. In addition, because foreign materials can enter the mechanical system during operation, oil analysis techniques further detect common contaminants found in the operating environment of the mechanical system or from the subsystems of the mechanical system. In addition, lubricant compositions also typically contain various additives that customize or improve the performance of the lubricant for various settings. In different lubricant formulations, a series of heterogeneous additives will produce different properties.

[0036] The SOA technique is performed on a running lubricant sample obtained from a mechanical system, where radiation is emitted from a radiation source, passes through the running lubricant sample, is captured by a radiation detector, and converted to an electrical signal by the radiation detector. The electrical signal is then converted to one or more spectral measurements, such as absorbance and transmittance.

[0037] According to AAS spectroscopy or ICP spectroscopy, the sample spectrum indicates the presence of various elements in the lubricating sample. According to FTIR spectroscopy, the sample spectrum generally indicates the presence of various molecular bonds constituting molecules in the lubricating sample.

[0038] To facilitate analysis of operating lubricant composition from a sample spectrum so that it is more efficient than manual analysis, a computing system may be configured to receive as input a sample spectrum of a sample of the operating lubricant, compare the sample spectrum to a reference spectrum of the same lubricant to derive a difference spectrum, and perform regression on the difference spectrum to determine a plurality of component spectra that make up the difference spectrum.

[0039] After the computing system determines the magnitude of the various component spectra, the computing system can calculate the concentration of the various substances in the lubricant sample.

[0040] Example embodiments of the present disclosure provide: a wear component comprising a sub-surface incipient failure indicator; a mechanical component comprising at least one wear component comprising a sub-surface incipient failure indicator; and a mechanical system comprising at least one mechanical component comprising at least one wear component comprising a sub-surface incipient failure indicator.

[0041] Figure 2 A cross-sectional view of an elastomeric seal 200 including an incipient failure region is illustrated. The incipient failure region 202 includes the hatched area of ​​at least one side or at least one radial slice of the elastomeric seal 200. During operation of the mechanical system, the elastomeric seal 200 providing a dynamic seal may move freely within the gland and, therefore, be subject to abrasive wear against adjacent surfaces of the gland. During operation of the mechanical system, the elastomeric seal 200 may be subject to a degree of abrasive wear on the same side while continuing to substantially provide a dynamic seal against the working fluid on one or more sides of the gland, as described above with reference to FIG. Figure 1 The incipient failure region 202 is generally no greater than and may be less than the region where frictional wear extending to the innermost edge of the region has not yet resulted in catastrophic failure of the dynamic seal.

[0042] According to an exemplary embodiment of the present disclosure, an elastomeric seal is manufactured as an elastomeric member including a subsurface incipient failure indicator. The failure indicator may include any combination of elemental substances or molecular compounds. The failure indicator may include any combination of particulate matter that is soluble or insoluble in the lubricant and hydrophobic molecules that are soluble in the lubricant.

[0043] The failure indicator may include any element having a characteristic spectrum that can be distinguished from the characteristic spectrum of metal wear compounds, the characteristic spectrum of contaminants, and the characteristic spectrum of lubricant additives in spectral analysis. The failure indicator may include any molecule having a characteristic spectrum that can be distinguished from the characteristic spectrum of metal wear compounds, the characteristic spectrum of contaminants, and the characteristic spectrum of lubricant additives in spectral analysis. In other words, the characteristic spectrum of one or more components of the failure indicator can be distinguished from the characteristic spectrum of one or more components of substances inherent to the operating mechanical system (hereinafter referred to as "operation-inherent component substances" for simplicity), even if such component substances are foreign to the newly assembled mechanical system.

[0044] The definition of operation-inherent components may be different for different mechanical systems in different operating environments and containing different lubricant additives. By way of example, for stationary machine tools operating indoors, soil may be excluded from possible contaminants, so silicon is unlikely to be present in the contaminants, while for mobile engineering machinery and agricultural machinery operating outdoors, soil is included in possible contaminants, so silicon may be present in the contaminants. By way of another example, for mechanical systems that add anti-wear additives to the lubricant, phosphorus and zinc may be present in the lubricant additives, while for mechanical systems that add detergent additives to the lubricant, calcium may be present in the lubricant additives. Therefore, different mechanical systems have different sets of operation-inherent components, and therefore, for these different mechanical systems, different sets of failure indicators may have characteristic spectra that can be distinguished from the characteristic spectra of the operation-inherent components.

[0045] However, according to example embodiments of the present disclosure, the failure indicator may also have a characteristic spectrum that is broadly distinguishable from the characteristic spectrum of the operating intrinsic component substances for the various mechanical systems. By way of example, elements and molecules that are not present in the lubricant (regardless of whether wear debris is present and whether the lubricant is single-grade or multi-grade) or lubricant additives (for the various mechanical systems), are not present in wear debris (for the various mechanical systems), and are not present in contaminants (for the operating environment of the various mechanical systems), and are additionally not present in the various mechanical systems themselves, will only increase in concentration during normal operation of the mechanical system if they are present as failure indicators.

[0046] For example, cerium is not present in lubricants or lubricant additives of various mechanical systems, is not present in wear debris of various mechanical systems, is not present in pollutants of the operating environment of various mechanical systems, and is not present in the various mechanical systems themselves. Therefore, for various mechanical systems, failure indicators containing cerium can have characteristic spectra that can be distinguished from characteristic spectra of operating inherent component substances.

[0047] For example, yttrium is not present in lubricants or lubricant additives of various mechanical systems, is not present in wear debris of various mechanical systems, is not present in contaminants of the operating environment of various mechanical systems, and is additionally not present in the various mechanical systems themselves. Therefore, for various mechanical systems, failure indicators containing yttrium may have a characteristic spectrum that can be distinguished from the characteristic spectrum of operating inherent component materials.

[0048] For example, lanthanum is not present in lubricants or lubricant additives of various mechanical systems, is not present in wear debris of various mechanical systems, is not present in contaminants of the operating environment of various mechanical systems, and is additionally not present in the various mechanical systems themselves. Therefore, for various mechanical systems, failure indicators containing lanthanum may have a characteristic spectrum that can be distinguished from the characteristic spectrum of the operating inherent component material.

[0049] For example, scandium is not present in lubricants or lubricant additives of various mechanical systems, is not present in wear debris of various mechanical systems, is not present in contaminants of the operating environment of various mechanical systems, and is additionally not present in the various mechanical systems themselves. Therefore, for various mechanical systems, failure indicators containing scandium may have a characteristic spectrum that can be distinguished from the characteristic spectrum of operating inherent component materials.

[0050] For example, zirconium is not present in lubricants or lubricant additives of various mechanical systems, is not present in wear debris of various mechanical systems, is not present in contaminants of the operating environment of various mechanical systems, and is additionally not present in the various mechanical systems themselves. Therefore, for various mechanical systems, failure indicators containing zirconium may have a characteristic spectrum that can be distinguished from the characteristic spectrum of the operating inherent component material.

[0051] Furthermore, it should be understood that the distinguishability of any failure indicator characteristic spectrum from any operation-inherent component material characteristic spectrum does not necessarily mean that the failure indicator is not present in the operation-inherent component material. On the contrary, even if the element or molecule of the failure indicator is also present in the operation-inherent component material at a non-negligible concentration, if the concentration of the element or molecule does not increase significantly during the operation life of the mechanical system, the characteristic spectrum of the failure indicator can still be distinguished from the characteristic spectrum of the operation-inherent component material.

[0052] By way of example, elements and molecules that are present in lubricant additives (for a particular mechanical system) but are not present in wear debris (for that particular mechanical system) and are not present in contaminants (for the operating environment of that particular mechanical system) will not increase significantly in concentration during normal operation of the mechanical system (and may decrease in concentration in the event of performance degradation or failure).

[0053] For example, molybdenum may be present in lubricant additives used in a particular mechanical system, is not typically present in contaminants, and is not present in wear debris unless the mechanical system includes a molybdenum alloy. Thus, for a mechanical system that does not include a molybdenum alloy, a failure indicator containing molybdenum may have a characteristic spectrum that can be distinguished from the characteristic spectrum of the operating inherent component material.

[0054] For example, magnesium may be present in lubricant additives used in certain mechanical systems, is not typically present in wear debris, and is not present in contaminants unless the mechanical system is operating in an environment where hard water or certain calcium-containing debris is present in large quantities. Therefore, for mechanical systems that do not operate in such environments, a failure indicator containing magnesium may have a characteristic spectrum that can be distinguished from the characteristic spectrum of materials inherent to the operation.

[0055] For example, lead is not present in lubricant additives, is not typically present in contaminants (in non-hazardous operating environments), and is typically present at background levels in wear debris in most mechanical systems. Thus, for most mechanical systems, a failure indicator containing lead may have a characteristic spectrum that is distinguishable from that of the operating intrinsic constituent materials (although due to the toxic properties of lead, it may be undesirable to introduce such high levels of lead into many mechanical systems unless the mechanical system is already operating in a toxic but substantially lead-free environment).

[0056] Therefore, it should be understood that while failure indicator elements and / or molecules may be embedded in non-metallic wear components to indicate abrasive wear, the failure indicator elements and / or molecules may still be metallic in nature.

[0057] Such failure indicator elements and / or molecules having characteristic spectra that can be distinguished from characteristic spectra of operating intrinsic components should not be limited to the above examples, and should be understood to cover any such elements and / or molecules that meet the above description of operating intrinsic components of operating mechanical systems; which themselves do not corrode, wear, damage or otherwise cause failure of elastomeric seals; which do not reduce the lubricating properties of lubricants and lubricant additives of operating mechanical systems; which exist in large quantities in at least non-diluted form (if not in pure form) and are easy to purchase in large quantities without geographical restrictions; and which do not chemically react with lubricants and lubricant additives of operating mechanical systems in a volatile or dangerous manner. Such failure indicator elements and / or molecules should also be non-toxic unless the mechanical system is operated in a toxic environment (but the environment is substantially free of failure indicator elements and / or molecules). For simplicity, such failure indicator elements and / or molecules will be referred to as "spectrally distinguishable" elements and / or molecules.

[0058] In addition, according to the SOA technique, the mechanical system generally includes a lubricant filter that excludes particulate matter above a certain size (hereinafter referred to as the "exclusion size limit") from the lubricant flowing through the filter. Therefore, downstream of the lubricant filter, large contaminant particles can be excluded from the lubricant. The lubricant sample for applying the SOA technique can be collected from upstream of the lubricant filter or downstream of the lubricant filter. If the failure indicator includes particulate matter that is insoluble in the lubricant, depending on the size of the failure indicator particulate matter, the lubricant sample collected for detecting the failure indicator element and / or molecule can be obtained upstream of the lubricant filter in the case where the failure indicator particulate matter is larger than the exclusion size limit of the lubricant filter; and the lubricant sample can be obtained downstream of the lubricant filter in the case where the failure indicator specific substance is smaller than the exclusion size limit of the lubricant filter.

[0059] By way of example, if the failure indicator particulate matter may interfere with the function of other mechanical components of the mechanical system, the particulate matter should be larger than the exclusion size limit of the lubricant filter and the lubricant sample should be obtained upstream of the lubricant filter. If the mechanical system is physically constructed so that it is difficult for personnel to access or contact the lubricant sample upstream of the lubricant filter, the particulate matter should have properties that rarely interfere with the function of other mechanical components of the mechanical system, and the lubricant sample can be obtained downstream of the lubricant filter.

[0060] In addition, for reasons that will be described in detail later, according to various exemplary embodiments of the present disclosure, the failure indicator may include elements and / or molecules that can withstand the vulcanization process (such as high temperature conditions) of elastomer molding. According to exemplary embodiments of the present disclosure, the elastomeric seal has one or more failure indicators, which include elements and / or molecules that are spectrally distinguishable at one or more sub-surface distances, including at least one sub-surface distance within the incipient failure region.

[0061] Figure 3 A cross-sectional view of an elastomeric seal 300 including an incipient failure region and a subsurface sublayer failure indicator is illustrated. The incipient failure region 302 includes the hatched area of ​​at least one exterior face of the elastomeric seal 300 (which may be circular, or may have any other geometric shape). At the inner edge of the incipient failure region 302 (where frictional wear to the inner edge has not substantially resulted in catastrophic failure of the dynamic seal), a failure indicator is embedded through a subsurface layer 304 of the elastomeric seal 300 across at least a portion of at least one exterior face of the elastomeric seal 300.

[0062] The distance from the subsurface layer 304 to the exterior face of the elastomeric seal 300 may be generally uniform (on a scale of millimeters) throughout the length of the subsurface layer 304, as illustrated by the distance between the exterior face of the elastomeric seal 300 and the subsurface layer 304. In the case where the cross-section of the elastomeric seal 300 is substantially circular, the subsurface layer 304 may generally circumferentially span at least a portion of the inner perimeter. In the case where the elastomeric seal has multiple faces, one or more subsurface layers 304 may be located below one or more faces of the elastomeric seal 300.

[0063] After the elastomeric seal 300 is installed in a mechanical system to provide a dynamic seal, over time during the operational life of the mechanical system, abrasive wear of the elastomeric seal 300 may expose at least a portion of the subsurface layer 304. Because the elastomeric seal 300 is lubricated like other wear components of the mechanical system (and the elastomeric seal 300 may otherwise be self-lubricating), exposure of the subsurface layer 304 causes the failure indicator, which includes spectrally distinguishable elements and / or molecules, to mix with the lubricant of the mechanical system, thereby being dissolved if the failure indicator includes hydrophobic molecules, and being entrained in the lubricant if the failure indicator includes particulate matter.

[0064] Thus, as described above, a computing system configured to perform spectral analysis on a lubricant sample from a mechanical system may be further configured to record failure indicating characteristic spectra of spectrally distinguishable elements or molecules of a failure indicator. The computing system may be further configured to detect whether the difference spectrum includes a failure indicating characteristic spectrum.

[0065] By way of example, the computing system may be configured to perform a regression on the difference spectrum to determine whether the failure-indicating characteristic spectrum is among the component spectra that make up the difference spectrum.

[0066] In the event that the computing system determines that the failure indication characteristic spectrum is among the component spectra, the mechanical system operator can, based on the determination, remove the mechanical system from operation and replace one or more elastomeric seals to prevent future performance degradation due to future incipient failure of one or more elastomeric seals and / or prevent further degradation of performance due to incipient failure of one or more elastomeric seals, thereby reducing the risk of one or more elastomeric seals reaching a catastrophic failure point.

[0067] According to example embodiments of the present disclosure, the same elastomeric seal may include multiple subsurface layers at different distances from the exterior face of the elastomeric seal, and the same or different failure indicators (each including different spectrally distinguishable elements and / or molecules) may be embedded above each different subsurface layer. Thus, over time, abrasive wear of the elastomeric seal may progressively expose at least a portion of the shallowest subsurface layer, then expose at least a portion of the next shallowest subsurface layer, and so on, until at least a portion of the deepest subsurface layer is exposed. The progressive exposure of each deeper subsurface layer causes the same failure indicator to mix with the lubricant of the mechanical system at progressively higher concentrations, or causes different failure indicators (including different spectrally distinguishable elements and / or molecules) to mix with the lubricant of the mechanical system.

[0068] Thus, as described above, a computing system configured to perform spectral analysis on a lubricant sample from a mechanical system may be further configured to detect whether a difference spectrum includes a failure indicating characteristic spectrum of lower magnitude or higher magnitude, wherein lower magnitude indicates that only shallower sub-surface layers have been exposed by friction and wear, while higher magnitude indicates that deeper sub-surface layers have been exposed by friction and wear.

[0069] The computing system may also be configured to record multiple failure indicator characteristic spectra of spectrally distinguishable elements or molecules of multiple failure indicators, each failure indicator characteristic spectrum being embedded in the elastomeric seal in a sequence from the shallowest subsurface layer to the deepest subsurface layer (hereinafter, "sequentially sequenced from the shallowest layer" shall mean that one or more of these failure indicator characteristic spectra are sequenced continuously from the shallowest layer). The computing system may be further configured to detect whether the difference spectrum includes one or more failure indicator characteristic spectra sequenced continuously from the shallowest layer.

[0070] By way of example, the computing system may be configured to perform a regression on the difference spectrum to determine whether one or more failure-indicating characteristic spectra that are ordered consecutively from the shallowest layer are among the component spectra that make up the difference spectrum. (Abrasive wear is less likely to expose discontinuous subsurface layers without exposing intermediate subsurface layers, or to expose deeper subsurface layers without exposing shallower subsurface layers; therefore, the computing system may be configured to reduce or decrease the likelihood that multiple failure-indicating characteristic layers that are not ordered consecutively from the shallowest layer are among the component layers of the difference spectrum.)

[0071] In the event that the computing system determines that one or more failure indicating characteristic spectra are sequentially ordered from the shallowest level among the component spectra, the mechanical system operator may decide whether to remove the mechanical system from operation and replace one or more elastomeric seals based on the determination. The presence of a failure indicating characteristic spectrum of smaller magnitude or the presence of fewer different failure indicating characteristic spectra may indicate that friction wear is in the early stages of incipient failure, and the presence of a failure indicating characteristic spectrum of larger magnitude or the presence of multiple different failure indicating characteristic spectra may indicate that friction wear is in the late stages of incipient failure.

[0072] According to example embodiments of the present disclosure, different elastomeric seals of the same mechanical system may include different failure indicators, each failure indicator including a different spectrally distinguishable element and / or molecule respectively embedded therein. Thus, abrasive wear of the different elastomeric seals may expose subsurface layers having different failure indicators embedded therein, each exposure causing a different spectrally distinguishable element and / or molecule to mix with the lubricant of the mechanical system.

[0073] Thus, as described above, a computing system configured to perform spectral analysis on a lubricant sample from a mechanical system may be further configured to record multiple failure indicating characteristic spectra of spectrally distinguishable elements or molecules of multiple failure indicators. The computing system may be further configured to detect whether the difference spectrum includes one or more of these failure indicating characteristic spectra. As long as the mechanical system does not include more than one elastomeric seal embedded with the same failure indicator, each different failure indicating characteristic spectrum may indicate frictional wear and incipient failure of a different elastomeric seal. A mechanical system operator may clearly identify and replace those elastomeric seals that exhibit frictional wear without having to manually inspect or replace elastomeric seals that do not exhibit frictional wear.

[0074] Additionally, for each replacement of an elastomeric seal, a machine system operator may rotate elastomeric seals for the machine system with progressively different failure indicators embedded for each replacement. Thus, detection of different failure indicating characteristic spectra may indicate that the elastomeric seal has been replaced multiple times in the machine system.

[0075] According to an example embodiment of the present disclosure, a hydraulic actuator assembly of a mechanical system may be installed with one or more elastomeric seals providing a dynamic seal, each elastomeric seal being embedded with a subsurface incipient failure indicator. By way of example, Figure 4 Illustrated Figure 1 A hydraulic cylinder 100 is provided which is equipped with an elastomeric seal providing a dynamic seal.

[0076] like Figure 1As illustrated, within each of the glands 114A, 118A, and 120A of the hydraulic cylinder 100, a corresponding elastomeric seal 414B, 418B, and 420B is disposed. Each of the elastomeric seals is confined within its corresponding gland by a surface adjacent to the side of the corresponding gland, which encloses the gland. Each of the elastomeric seals is free to move within its corresponding gland, providing a dynamic seal.

[0077] As mentioned above Figure 3 As described, according to various exemplary embodiments of the present disclosure, each of the elastomeric seals 414B, 418B, and 420B may have the same failure indicator embedded therein; each of the elastomeric seals 414B, 418B, and 420B may have a different failure indicator embedded therein. Therefore, both the piston seal and the rod seal of the hydraulic cylinder may have a failure indicator embedded therein. In addition, any, some, or all of the elastomeric seals 414B, 418B, and 420B may have more than one different failure indicator embedded therein at multiple subsurface layers at different depths.

[0078] In addition, according to the exemplary embodiments of the present disclosure, the mechanical system may be installed with any number of hydraulic actuator assemblies, each of which is as described above. Figure 4 As illustrated, one or more elastomeric seals are installed to provide a dynamic seal, each elastomeric seal being embedded with a sub-surface incipient failure indicator.

[0079] As mentioned above Figure 3 and Figure 4 As described, according to various example embodiments of the present disclosure, each of the elastomeric seals of such a mechanical system may have the same failure indicator embedded therein; and each of the elastomeric seals of such a mechanical system may have a different failure indicator embedded therein. In addition, the elastomeric seal of the first hydraulic actuator assembly may have a first failure indicator embedded therein, and the elastomeric seal of the second hydraulic actuator assembly may have a second failure indicator embedded therein. As long as the mechanical system does not include more than one hydraulic actuator assembly and the hydraulic actuator assembly has an elastomeric seal embedded with the same failure indicator, each different failure indication characteristic spectrum may indicate the frictional wear and incipient failure of the elastomeric seals of the different hydraulic actuator assemblies. The mechanical system operator can specifically repair and replace the elastomeric seal of one hydraulic actuator assembly without having to manually inspect or replace the elastomeric seals of different hydraulic actuator assemblies that do not exhibit frictional wear.

[0080] Any, some, or all of the elastomeric seals of the mechanical system may have more than one different failure indicator embedded therein at multiple sub-surface layers at different depths.

[0081] According to example embodiments of the present disclosure, an elastomeric seal embedded with a subsurface sublayer incipient failure indicator can be manufactured by various manufacturing processes, wherein the elastomeric member can be manufactured in more than one stage, or manufactured as two members that are subsequently bonded. Thus, an inner core member of the elastomeric seal (not part of the incipient failure region) can be first manufactured by subjecting a polymer material to a molding and vulcanization process; a failure indicator can be applied to at least a portion of the outer face of the inner core; and an outer layer member of the elastomeric seal can be manufactured on the inner core by subjecting an additional polymer material to a molding and vulcanization process, wherein the outer layer can be molded over the top of the inner core or the outer layer can be molded separately and bonded to the inner core. According to example embodiments of the present disclosure, the process can be repeated, wherein each outer layer becomes the outer face of a new inner core, the new inner core having the same or different failure indicator applied to its outer face, and then a new outer layer is molded over the top of it, or a new outer layer is molded separately and bonded thereto.

[0082] By way of example, such manufacturing processes may include a two-shot molding process, such as an overmolding process. By such a process, the inner core may be molded and cured in a smaller mold; a failure indicator may be applied to at least a portion of the outer face of the inner core; and the inner core to which the failure indicator is applied may be placed in a larger mold, wherein an outer layer is molded and cured around the inner core. The process may be repeated to embed the failure indicator in multiple subsurface layers, progressively molding an outer layer over each subsurface layer. The failure indicator should include elements and / or molecules that withstand high temperature conditions in order to withstand the vulcanization process as described above.

[0083] By way of example, such a manufacturing process may include a vulcanization bonding process. By such a process, an inner core may be molded and cured in a first mold; a failure indicator may be applied to at least a portion of an outer face of the inner core; an outer layer may be molded and cured in a second mold; and the outer layer may be bonded to the outer face of the inner core by further vulcanizing the outer layer and the inner core. The process may be repeated to embed the failure indicator in multiple subsurface layers, progressively bonding the outer layer over each subsurface layer. The failure indicator should include elements and / or molecules that withstand high temperature conditions in order to withstand the vulcanization process as described above.

[0084] By way of further example, any elastic manufacturing technique that bonds two elastomeric members may embed a failure indicator between the two bonded members according to an example embodiment of the present disclosure. For example, a conveyor belt may be manufactured by splicing two elastomeric members joined end-to-end or by the edges of mating counterparts. According to an example embodiment of the present disclosure, a failure indicator may be applied to the joint between the two elastomeric members, thereby producing a conveyor belt having an underlying incipient failure indicator embedded therein.

[0085] In addition, the present disclosure provides a wear indicator carried in a sealed cavity of a mechanical system ("cavity-borne wear indicator"). The mechanical system may include a hollow cavity that is sealed to block the passage of free mechanical elements, but not the passage of fluids. By way of example, the pistons and / or rods of other actuators, including hydraulic actuators, pneumatic actuators, and internal combustion engine actuators, may be carried by their directional motion through linear bearings, which are mechanical assemblies that carry the load of pistons and rods, etc. within two circular tracks, and rolling elements are accommodated between the two circular tracks to reduce the friction of the load. Similarly, rotating elements such as shafts and shafts may be carried by their rotational motion through rotating bearings that carry the load in a similar manner. In either case, the sides of the circular tracks may be sealed by elastomeric seals that seal the rolling elements within the cavity, and external contamination and leakage are prevented from entering the cavity. Such elastomeric seals are also wear components described herein.

[0086] According to example embodiments of cavity-borne wear indicators, a wear indicator as described above may be carried in a solvent or non-solvent fluid and carried in a sealed cavity of a mechanical system, or a fluid wear indicator may be carried in a sealed cavity of a mechanical system. As described above, the wear indicator may be gradually released from the sealed cavity after a wear component sealing the sealed cavity begins to exhibit incipient failure. Failure indicators including spectrally distinguishable elements and / or molecules may be mixed with a coolant of the mechanical system, thereby being soluble in the coolant if the failure indicator includes hydrophilic molecules, and being carried in the coolant if the failure indicator includes particulate matter.

[0087] A computing system configured to perform spectral analysis on a coolant sample from a mechanical system, as described above, may detect whether a difference spectrum includes a failure-indicating characteristic spectrum.

[0088] Figure 5 An example computing system 500 is illustrated for implementing the spectral analysis techniques described above.

[0089] The techniques and mechanisms described herein may be implemented by multiple instances of the computing system 500 , as well as by any other computing devices, systems, and / or environments. Figure 5 The computing system 500 shown is only one example of a system and is not intended to impose any limitation on the scope of use or functionality of any computing device used to perform the above-described processes and / or flows. Other well-known computing devices, systems, environments, and / or configurations that may be suitable for use with the various embodiments include, but are not limited to, personal computers, server computers, handheld or laptop devices, multiprocessor systems, microprocessor-based systems, set-top boxes, game consoles, programmable consumer electronics, network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above-described systems or devices, implementations using field programmable gate arrays ("FPGAs") and application-specific integrated circuits ("ASICs"), and / or the like.

[0090] The computing system 500 may include one or more processors 502 and a system memory 504 communicatively coupled to the processor 502. The processor 502 and the system memory 504 may be physical or may be virtualized and / or distributed. The processor 502 may execute one or more modules and / or processes to enable the processor 502 to perform various functions. In an embodiment, the processor 502 may include a central processing unit ("CPU"), a graphics processing unit (GPU), both the CPU and the GPU, or other processing units or components known in the art. Additionally, each of the processors 502 may have its own local memory, which may also store program modules, program data, and / or one or more operating systems.

[0091] System memory 504 may be volatile (such as RAM), non-volatile (such as ROM), flash memory, a micro hard drive, a memory card, etc., or some combination thereof, depending on the exact configuration and type of system 500. System memory 504 may include one or more computer executable modules 506 that can be executed by processor 502.

[0092] Module 506 may include, but is not limited to, a spectrum receiving module 508 , a spectrum difference module 510 , and a spectrum regression module 512 .

[0093] The spectrum receiving module 508 may configure one or more processors to sample a spectrum of a running lubricant sample as input as described above.

[0094] The spectral difference module 510 may configure one or more processors to compare the sample spectrum to a reference spectrum of the same lubricant to derive a difference spectrum as described above.

[0095] The spectral regression module 512 may configure one or more processors to perform a regression on the difference spectrum to determine a plurality of component spectra that make up the difference spectrum as described above.

[0096] The computing system 500 may additionally include an input / output (I / O) interface 540 that allows the computing system 500 to communicate with an input device (such as a radiation detector as described above) that converts radiation into electrical signals and converts the electrical signals into one or more spectral measurements; and a communication module 550 that allows the computing system 500 to communicate with other systems and devices over a network. The network may include the Internet, wired media (such as a wired network or a direct wired connection), and wireless media (such as acoustic media, radio frequency ("RF") media, infrared media, and other wireless media).

[0097] Some or all of the operations of the above methods may be performed by executing computer-readable instructions stored on a computer-readable storage medium as defined below. The term "computer-readable instructions" as used in the specification and claims includes routines, applications, application modules, program modules, programs, components, data structures, and algorithms, etc. The computer-readable instructions may be implemented on a variety of system configurations, including single-processor or multi-processor systems, minicomputers, mainframe computers, personal computers, handheld computing devices, microprocessor-based systems, programmable consumer electronics, and combinations thereof, etc.

[0098] Computer-readable storage media may include volatile memory (such as random access memory ("RAM")) and / or non-volatile memory (such as read-only memory ("ROM"), flash memory, etc.). Computer-readable storage media may also include additional removable and / or non-removable storage devices, including but not limited to flash memory, magnetic storage devices, optical storage devices, and / or tape storage devices that can provide non-volatile storage of computer-readable instructions, data structures, program modules, etc.

[0099] Non-transitory computer-readable storage media are examples of computer-readable media. Computer-readable media include at least two types of computer-readable media, namely computer-readable storage media and communication media. Computer-readable storage media include volatile and non-volatile, removable and non-removable media implemented in any process or technology for storing information such as computer-readable instructions, data structures, program modules or other data. Computer-readable storage media include, but are not limited to, phase change memory ("PRAM"), static random access memory ("SRAM"), dynamic random access memory ("DRAM"), other types of random access memory ("RAM"), read-only memory ("ROM"), electrically erasable programmable read-only memory ("EEPROM"), flash memory or other memory technology, compact disk read-only memory ("CD-ROM"), digital versatile disk ("DVD") or other optical storage device, cassette, tape, disk storage device or other magnetic storage device, or any other non-transmitting medium that can be used to store information for access by a computing device. In contrast, communication media can embody computer-readable instructions, data structures, program modules or other data in a modulated data signal (such as a carrier) or other transmission mechanism. As defined herein, computer-readable storage media do not include communications media.

[0100] Computer-readable instructions stored on one or more non-transitory computer-readable storage media may perform the above operations when executed by one or more processors: Generally, computer-readable instructions include routines, programs, objects, components, and data structures that perform specific functions or implement specific abstract data types. The order in which the operations are described is not intended to be construed as a limitation, and any number of the described operations may be combined in any order and / or in parallel to implement the process.

[0101] Industrial Applicability

[0102] It is desirable to detect wear, galling, cracking, screw failures, and other such incipient failure modes in wear components of a mechanical system during the earliest possible stage before such failures result in leakage and affect mechanical performance (such as hydraulic cylinder performance). However, because wear components (such as elastomeric seals) are deeply integrated into the operating machinery and cannot be accessed unless the machinery component is disassembled, and the machinery component cannot be accessed unless the entire mechanical system is removed from use and disassembled (e.g., on a machine such as an excavator or aerial work platform where the hydraulic cylinder is significantly elevated), it is desirable to detect incipient failures in wear components without direct physical access to the wear components.

[0103] The mechanical system includes non-metallic wear components, such as elastomeric seals. The elastomeric seals are formed of elastomeric compounds that do not include pure elements, and the characteristic spectrum of the elastomeric compound can be easily distinguished from the characteristic spectrum of the operating lubricant by spectral analysis targeting elemental composition. In addition, the polymer crosslinks that constitute the elastomeric seals have similar molecular bonds as the lubricant (both include many hydrocarbon molecules), so they also do not include molecules whose characteristic spectrum can be easily distinguished from the characteristic spectrum of the operating lubricant by spectral analysis targeting molecular composition.

[0104] Thus, while the incipient failure of metallic wear components may be indirectly detected during the operational life of a mechanical system via SOA techniques, the incipient failure of non-metallic wear components cannot be easily detected in a similar manner. As a result, wear of non-metallic wear components is more easily detected by inspection, which can only be performed when the mechanical system is removed from operation; if the incipient failure of an elastomeric seal in a mechanical system occurs earlier than the detection of the incipient failure of a mechanical wear component, the mechanical system operator may have no reason to remove the mechanical system from operation (which may be a costly process) to inspect the wear of the elastomeric seal, and thus the mechanical system may suffer from degraded, suboptimal performance (which may itself incur costs) for a period of time before the incipient failure can be detected. In addition, the mechanical system operator may only replace elastomeric seals after the mechanical system has been in operation for a certain number of operating hours; such replacement policies are rigid and inflexible, and do not reflect the actual state of the dynamic sealing provided by these seals, which may or may not have been degraded.

[0105] Therefore, according to an example embodiment of the present disclosure, spectral analysis performed on a lubricant sample from a mechanical system can further identify a failure-indicating characteristic spectrum of a spectrally distinguishable element or molecule of a failure indicator. By receiving a sample spectrum of a running lubricant sample as input, comparing the sample spectrum with a reference spectrum for the same lubricant to derive a difference spectrum, and performing regression on the difference spectrum to determine a plurality of component spectra constituting the difference spectrum, it can be determined whether the failure-indicating characteristic spectrum is among the component spectra constituting the difference spectrum.

[0106] Upon determining that the failure indication characteristic spectrum is within the component spectrum, the mechanical system operator may, based on this determination, remove the mechanical system from operation and replace one or more elastomeric seals to prevent future performance degradation due to future incipient failure of one or more elastomeric seals and / or prevent further degradation of performance due to incipient failure of one or more elastomeric seals, thereby reducing the risk of one or more elastomeric seals reaching a catastrophic failure point.

[0107] Although various aspects of the present disclosure have been specifically shown and described with reference to the above embodiments, it will be understood by those skilled in the art that various additional embodiments may be conceived by modifying the disclosed machines, systems and methods without departing from the spirit and scope of the disclosed content. These embodiments should be understood to fall within the scope of the present disclosure as determined based on the claims and any equivalents thereof.

[0108] Recitation of ranges of values ​​herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein.

Claims

1. An elastomeric member (300), comprising: external face; a first subsurface layer (304) underlying at least a portion of the exterior face; and a first incipient failure indicator, the first incipient failure indicator being embedded through the first subsurface layer (304); The first incipient failure indicator includes an element or molecule that can be spectrally distinguished from an inherent component of the mechanical system.

2. The elastomeric member (300) of claim 1, wherein the distance from the first sub-surface layer (304) to the outer surface of the elastomeric member (300) is substantially uniform over the entire length of the sub-surface layer (304).

3. The elastomeric member (300) according to claim 1, further comprising: a second subsurface layer (304) underlying at least a portion of the exterior face; Wherein the first subsurface layer (304) and the second subsurface layer (304) are located below the outer surface at a plurality of subsurface distances.

4. The elastomeric member (300) of claim 1, wherein the first incipient failure indicator comprises particulate matter that is smaller than an exclusion size limit of a lubricant filter of the mechanical system.

5. The elastomeric member (300) of claim 1, wherein the first incipient failure indicator comprises one of cerium, yttrium, lanthanum, scandium, zirconium, molybdenum, magnesium, or lead.

6. An actuator (100), comprising: Cylinder (104); A piston member (108); A rod member (106); a first elastomeric seal (420B) mounted in a circumferential first gland (120A) of the piston member (108) adjacent the barrel (104); and a second elastomeric seal (414B) fitted into a circumferential second gland (114A) of the barrel (104) adjacent the stem (106); wherein the first elastomeric seal (420B) includes a first subsurface layer (304), the first subsurface layer having a first incipient failure indicator embedded through the first subsurface layer (304); and Wherein the second elastomeric seal (414B) includes a second sub-surface layer (304), the second sub-surface layer having a second incipient failure indicator embedded through the second sub-surface layer (304).

7. The actuator (100) of claim 6, wherein the first incipient failure indicator and the second incipient failure indicator each comprise an element or molecule that is spectrally distinguishable from a component substance inherent to the operation of the mechanical system.

8. The actuator (100) of claim 6, wherein the first elastomeric seal (420B) includes a third subsurface layer (304) having the first incipient failure indicator embedded through the third subsurface layer (304); and Wherein the second elastomeric seal (414B) includes a fourth sub-surface layer (304), the fourth sub-surface layer having the second incipient failure indicator embedded through the fourth sub-surface layer (304).

9. The actuator (100) of claim 6, wherein the first elastomeric seal (420B) includes a third subsurface layer (304) having a third incipient failure indicator embedded through the third subsurface layer (304); and wherein the second elastomeric seal (414B) includes a fourth subsurface layer (304), the fourth subsurface layer having a fourth incipient failure indicator embedded through the fourth subsurface layer (304); wherein the first incipient failure indicator and the third incipient failure indicator respectively include different elements or different molecules; and The second incipient failure indicator and the fourth incipient failure indicator include different elements or different molecules respectively.

10. The actuator (100) of claim 6, wherein the first incipient failure indicator and the second incipient failure indicator each include particulate matter that is smaller than an exclusion size limit of a lubricant filter of a mechanical system.

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