Insulating fluid or gas absorbent for use in an electrical apparatus

Abstract

The present disclosure relates to the use of a compound of Formula (I) as an insulating fluid or a gas absorbent in an electrical apparatus. The disclosure also relates to an insulating fluid or a gas absorbent for use in an electrical apparatus and an electrical apparatus comprising such insulating fluid or gas absorbent. Besides, the present disclosure relates to a method for preparing an electrical apparatus comprising such insulating fluid or gas absorbent and a method for absorbing a gas component in an electrical apparatus.

Description

[0001] INSULATING FLUID OR GAS ABSORBENT FOR USE IN AN ELECTRICAL APPARATUS

[0002] FIELD

[0003] The present disclosure generally relates to an insulating fluid or a gas absorbent for use in an electrical apparatus, an electrical apparatus comprising the same, a method for preparing an electrical apparatus and a method for absorbing a gas component in an electrical apparatus.

[0004] BACKGROUND

[0005] Insulating fluid is widely used in applications in electrical equipment to provide insulation, cooling and arc extinguishing effects. Currently, researchers generally focus on the dielectric and flow properties of insulating liquids to develop new insulating liquids.

[0006] Gassing of insulating oil is defined as the chemical decomposition of certain vulnerable hydrocarbons, under the impact of electrical and thermal stresses. The primary decomposition process involves generation of short-lived free radicals via splitting up of covalent bonds in oil molecules as: R-H (hydrocarbon) — R* + »H.

[0007] Large free radicals (R») may lead to formation of insoluble colloidal compounds (a sludge in solid phase): R* + »R — R-R (insoluble sludge) while small free radicals (H») may result in gaseous inclusions such as hydrogen (H2) gas: H* + »H — H2 $ (soluble gas).

[0008] It is known that partial discharges (PD) tend to occur in such gaseous inclusions, and therefore the resistance to gassing of insulating liquid will affect the stability of liquid to electrical discharge. Depending on the natures of the liquid, the volume of the gas subjected to the discharges may decrease (gas-absorbing liquid) or increase (gas-evolving liquid).

[0009] In a strong gas-absorbing liquid (negative gassing tendency), discharges will quickly disappear, whereas in a gas-evolving liquid (positive gassing tendency), more discharges will be produced, leading to eventual insulation breakdown.

[0010] Therefore, in addition to insulation, cooling and arc extinguishing effects, the gassing property of an insulating liquid, i.e., its tendency to absorb or evolve gases, has been recognized as a factor of importance in developing a dielectric liquid. Meanwhile, the gassing property is considered as a symptom of a potential threat to the operational safety of liquid-filled electric power equipment as well.

[0011] WO2016167176A1 discloses an electrically insulating oil base oil for an oil-filled electrical device, containing a specific fatty acid ester from fatty acid / aromatic alcohol. Such electrically insulating oil has good partial discharge characteristics and biodegradability.

[0012] W02007126207A1 discloses a vegetable-based electrical insulating oil which exhibits superior anti-oxidability and is readily biodegradable in ecosystems after use via characteristics of vegetable oil.

[0013] It is desirable in the field to develop an insulating fluid with excellent negative gassing tendency or a gas absorbent that may impart excellent negative gassing tendency to an insulating fluid.

[0014] SUMMARY

[0015] In one aspect, provided herein is use of a compound of Formula (I) as an insulating fluid or a gas absorbent in an electrical apparatus, Formula (I), wherein Mi and M2 are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; x and y are each independently 0 or 1; R1and R2are each independently Ce-io aryl; R1and R2are each independently and optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen.

[0016] In some embodiments, Mi and M2 are each independently methylene. In some embodiments, at least one of R1and R2is phenyl, preferably both of R1and R2are phenyl. In some embodiments, x is 0, and y is 1.

[0017] In a specific embodiment, the compound of Formula (I) has the following formula:

[0018] In another aspect, provided herein is an insulating fluid or a gas absorbent for use in an electrical apparatus, comprising a component (A) selected from the group consisting of a compound of Formula (I):

[0019] O

[0020] R1- ( xM vx x — C — O — (M2)V- R2r,T\ 'yFormula (I), wherein Mi and M2 are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; x and y are each independently 0 or 1; R1and R2are each independently Ce-io aryl; R1and R2are each independently and optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen.

[0021] In some embodiments, Mi and M2 are each independently methylene. In some embodiments, at least one of R1and R2is phenyl, preferably both of R1and R2are phenyl. In some embodiments, x is 0, and y is 1.

[0022] In a specific embodiment, the compound of Formula (I) has the following formula:

[0023] In another aspect, provided herein is an electrical apparatus comprising the insulating fluid or gas absorbent as described herein.

[0024] In another aspect, provided herein is a method for preparing an electrical apparatus, comprising providing an electrical apparatus and filling the insulating fluid or gas absorbent as described herein into the electrical apparatus.

[0025] In another aspect, provided herein is a method for absorbing a gas component in an electrical apparatus, comprising applying the insulating fluid or gas absorbent as described herein to the electrical apparatus.

[0026] In some embodiments, the electrical apparatus may comprise or comprise a part of a: capacitor, transformer, voltage transformer, current transformer, reactor, cable system, bushing, converter, or a component and / or a combination thereof.

[0027] DETAILED DESCRIPTION OF EMBODIMENTS

[0028] General Definition and Terms

[0029] Unless otherwise stated, all publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety.

[0030] Unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by a person skilled in the art. If there is a contradiction, the definition provided in this application shall prevail.

[0031] Unless otherwise stated, all percentages, parts, proportions or the like are on a weight basis. When an amount, concentration or other value or parameter is given as a range, a preferable range or a preferable upper limit and lower limit or a specific value, it should be understood that it corresponds to specifically revealing any range by combining any pair of upper limit of the range or preferable range value with the lower limit of any range or preferable range value, regardless of whether the range is specifically disclosed. Unless otherwise stated, the numerical ranges listed herein are intended to include the endpoints of the range and all integers and fractions within the range.

[0032] When used with a numerical variable, the term “about” or “approximate” usually refers to the value of the variable and all the values of the variable within the experimental error (for example, within an average 95% confidence interval) or within ±10% of the specified value, or a wider range.

[0033] The term “optional” or “optionally” as used herein means the event described subsequent thereto may or may not happen. This term encompasses the cases that the event may or may not happen, and that the contents are selected in an arbitrary manner.

[0034] The terms “include”, “comprise”, “have”, “contain” or “involve” and other variants thereof as used herein are meant to be inclusive or open-ended, which do not exclude other unlisted elements or process steps. It should be understood by those skilled in the art that the above terms such as “include” encompass the meaning of “consist of’. The expression “consist of’ excludes any element, step, or ingredient not designated. The expression “substantially consist of’ means that the scope is limited to the designated elements, steps or ingredients, plus elements, steps or ingredients that are optionally present which do not substantially affect the basic and new features of the claimed subject matter. It should be understood that the expression “comprise” encompasses the expressions “substantially consist of’ and “consist of’.

[0035] The term “selected from” as used herein refers to one or more elements of the group listed thereafter, selected independently, and may encompass the combination of two or more elements.

[0036] The term “one or more” or “at least one” as used herein means one, two, three, four, five, six, seven, eight, nine or more.

[0037] Unless otherwise stated, the terms “combination thereof’ and “mixture thereof’ as used herein mean multicomponent mixtures of the elements, such as two, three, four and up to the maximum possible multicomponent mixtures.

[0038] If the number of parts or components of the present disclosure is not indicated before, it means that there is no limit to the number of parts or components. Therefore, it should be interpreted as including one or at least one, and the singular word form like “a”, “an”, “the” or the like of a part or component also includes the plural, unless the numerical value clearly indicates the singular.

[0039] As used herein, and unless otherwise specified, the term “insulating fluid”, also described as “insulating oil”, refers to a liquid that is electrically insulating.

[0040] As used herein, and unless otherwise specified, the term “gas-absorbent” refers to a substance that can absorb gases. Gases can be absorbed by any means, preferably by chemical reaction. The absorbed gas herein refers mainly to hydrogen gas and gaseous hydrocarbons (e.g., methane, ethane, ethylene, acetylene, etc.).

[0041] As used herein, generally the term “medium voltage” relates to voltages in the range of 10 kV to 35 kV, and the term “high voltage” relates to voltages above this range.

[0042] As used herein, and unless otherwise specified, the term “hydroxyl” refers to “-OH”. The term “carboxyl” refers to “-COOH”. The term “amino” refers to “-NH2”. The term “nitro” refers to “-NO2”. The term “halogen” refers to “-F”, “-C1”, “-Br” or “-I”.

[0043] As used herein, and unless otherwise specified, the term “hydrocarbon chain” refers to a straight or branched hydrocarbon chain linking the rest of the molecule to a radical group, consisting solely of carbon and hydrogen, which is saturated or contains one or more carboncarbon double or triple bonds. In one embodiment, the hydrocarbon chain may comprise 1 to 5 carbon atoms, e.g., 1, 2, 3, 4 and 5. Examples of hydrocarbon chain comprising 1 to 5 carbon atoms include, but are not limited to, methylene (-CH2-), ethylene (-CH2CH2-), propylene (- CH2CH2CH2-), n-butylene (-CH2CH2CH2CH2-), n-pentene (-CH2CH2CH2CH2-), ethenylene (- CH=CH-), propenylene (-CH=CHCH2-), n-butenylene (-CH=CHCH2CH2-) and the like.

[0044] As used herein, and unless otherwise specified, the term “aryl” refers to a monocyclic aromatic group and / or multicyclic monovalent aromatic group that contain at least one aromatic hydrocarbon ring. In certain embodiments, the aryl has from 6 to 10 ring carbon atoms (Ce-Cio aryl). Examples of aryl groups include, but are not limited to, phenyl, naphthyl. The term “aryl” also refers to bicyclic, tricyclic, or other multicyclic hydrocarbon rings, where at least one of the rings is aromatic and the others of which may be saturated, partially unsaturated, or aromatic, for example, dihydronaphthyl, indenyl, indanyl, or tetrahydronaphthyl (tetralinyl). Unless otherwise specified, an aryl group is optionally substituted.

[0045] As used herein, and unless otherwise specified, the term “hydrocarbyl” includes alkyl, alkenyl and alkynyl. The term “alkyl” refers to a straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms, which is saturated. The term “alkenyl” refers to a straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms, which contains one or more carbon-carbon double bonds. The term “alkynyl” refers to a straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms, which contains one or more carbon-carbon triple bonds. In certain embodiments, the hydrocarbyl comprises 1 to 10 carbon atoms (Ci-io hydrocarbyl), for example Ci-io alkyl, Ci-io alkenyl, and Ci-io alkynyl, e.g., Ci, C2, C3, C4, C5, Ce, C7, Cs, C9, Cio-alkyl, -alkenyl, and - alkynyl. In certain embodiments, the hydrocarbyl comprises 1 to 17 carbon atoms (C1.17 hydrocarbyl), for example C1.17 alkyl, C1.17 alkenyl, and C1.17 alkynyl, e.g., Ci, C2, C3, C4, C5, Ce, C7, Cs, C9, C10, C11, C12, C13, C14, C15, Cie, Crz-alkyl, -alkenyl, and -alkynyl. Examples include, but are not limit to methyl (-CH3), ethyl (-CH2CH3), n-propyl (-CH2CH2CH3), 1- methylethyl (isopropyl, -CH(CH3)2), n-butyl (-CH2CH2CH2CH3), n-pentyl (- CH2CH2CH2CH2CH3), 1,1 -dimethylethyl (t-butyl, -C(CH3)3), 3-methylhexyl (- CH2CH2CH(CH3)CH2CH2CH3), 2-methylhexyl (-CH2CH(CH3)CH2CH2CH2CH3), ethenyl (- CEUCH2), prop-l-enyl (-CH=CHCH,), prop-2-enyl (-CH2CEUCH2), but-l-enyl (- CH=CHCH2CH3), but-2-enyl (-CH2CH=CHCH3), but-3-enyl (-CH2CH2CH=CH2), pent-l-enyl (-CH=CHCH2CH2CH3), pent-2-enyl (-CH2CH=CHCH2CH3), pent-3 -enyl (- CH2CH2CH=CHCH3), pent-4-enyl (-CH2CH2CH2CH=CH2), penta- 1,4-dienyl (- CH=CHCH2CH=CH2), ethynyl (-C=CH), prop-l-ynyl (-C=CCH3), prop-2-ynyl (-CHC=CH), but-l-ynyl (-C^CCEbCEh), but-2-ynyl (-CHOCCH,), but-3-ynyl (-CH2CH2OCH), pent-1- ynyl (-C=CCH2CH2CH3), pent-2-ynyl (-CH2C=CCH2CH3), pent-3 -ynyl (-CH2CH2C=CCH3), pent-4-ynyl (-CH2CH2CH2C=CH) and the like.

[0046] Use as an insulating fluid or a gas absorbent

[0047] In one aspect, provided herein is use of a compound of Formula (I) as an insulating fluid or a gas-absorbent in an electrical apparatus, Formula (I), wherein Mi and M2are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; x and y are each independently 0 or 1; R1and R2are each independently Ce-io aryl; R1and R2are each independently and optionally substituted by one or more substituents selected from CMO hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen, preferably selected from CMO hydrocarbyl.

[0048] The “x” and “y” are used herein to indicate whether Mi and M2are present in Formula (I), respectively.

[0049] For example, x as 0 means that there is no Mi in Formula (I) and R1is directly covalently bonded to the carbon atom in the ester moiety; and x as 1 means that R1is covalently bonded to one end of Mi and the other end of Mi is covalently bonded to the carbon atom in the ester moiety.

[0050] Such a principle also applies to y similarly. For example, y as 0 means that there is no M2in Formula (I) and R2is directly covalently bonded to the oxygen atom in the ester moiety; and y as 1 means that R2is covalently bonded to one end of M2and the other end of M2is covalently bonded to the oxygen atom in the ester moiety.

[0051] As linking segments, Mi and M2may affect the properties of the compound of Formula (I), such as gas-absorbing and flowing properties. In some embodiments, Mi is a hydrocarbon chain comprising from 1 to 5 carbon atoms, and M2is also a hydrocarbon chain comprising from 1 to 5 carbon atoms. Mi and M2may be identical or different.

[0052] Examples of hydrocarbon chain comprising from 1 to 5 carbon atoms include, but are not limit to methylene, ethylene, propylene, n-butylene, n-pentene, ethenylene, propenylene, n- butenylene and the like.

[0053] The hydrocarbon chain with the carbon atoms within the above range may be advantageous for the compound of Formula (I) with good flowing properties. An overly long hydrocarbon chain may lead to a decrease in the flowing properties and may increase the risk of decomposition process, leading to gas generation on vulnerable hydrocarbons.

[0054] In some preferable embodiments, in Formula (I), Mi and M2are each independently methylene due to better stability and lower cost of the compound. In some more preferable embodiments, M2 is methylene.

[0055] In some embodiments, x is 0 and y is 1. The compound of Formula (I) can be prepared via esterification of a benzoic acid and an aromatic alcohol. The compound of Formula (I) may be of good stability and low cost.

[0056] Due to the inherent resistance to oxidation, hydrolysis and cleavage of the aryl groups in R1and R2, the compound of Formula (I) has good stability under operating and non-operating conditions of electrical apparatus. Meanwhile, the aryl groups in R1and R2render the compound of Formula (I) good reactivity to the undesirable gas (such as hydrogen gas) generated during the operation of the apparatus. Therefore, owing to the aryl groups in R1and R2, the compound of Formula (I) exhibits outstanding gas-absorbing properties.

[0057] In some preferable embodiments, R1and R2are each independently phenyl or naphthyl. As aryl groups consisting solely of aromatic rings, phenyl and naphthyl are less likely to undergo decomposition process during the operation of the electrical apparatus, even under harsh operation conditions (e.g., medium to high voltage conditions, high temperature and etc.), while phenyl and naphthyl can maintain good reactivity to the undesirable gas (such as hydrogen gas). Therefore, the compound of Formula (I) in which R1and R2are each independently phenyl or naphthyl shows better gas-absorbing properties.

[0058] In some more preferable embodiments, at least one of R1and R2is phenyl. In some most preferable embodiments, both R1and R2are phenyl. Compared to other Ce-io aryl groups, phenyl in R1and R2may give the compound of Formula (I) better gas-absorbing properties as well as flowing properties. In some specific embodiments, the compound of Formula (I) may include, but are not limit to the following structures:

[0059] In some embodiments, the compound of Formula (I) is benzyl benzoate, wherein x is 0 and y is 1; M2 is methylene; and both of R1and R2are unsubstituted phenyl. Benzyl benzoate is a synthetic ester with excellent gas-absorbing property, stability as well as low cost. The structure of benzyl benzoate is shown in the following formula: (Benzyl benzoate).

[0060] The compound of Formula (I) shows excellent dielectric properties (e.g., high breakdown voltage, high permittivity) and gas-absorbing properties, and therefore it is suitable for use as an insulating fluid in an electrical apparatus, especially in an electrical apparatus where a negative gassing tendency is a sought-after property.

[0061] In addition, the compound of Formula (I) exhibits remarkable gas-absorbing properties, enabling its use as a gas absorbent in an electrical apparatus. With a small amount of a compound of Formula (I), such as benzyl benzoate, the gas-absorbing properties of an insulating fluid system can be significantly improved, while the other advantageous properties of the insulating fluid system can remain substantially unaltered. Therefore, the compound of Formula (I) can be used as a gas absorbent in a wide range of insulating fluid systems, thereby improving the gas absorption of the system without undesirable negative effects.

[0062] Particularly, the electrical apparatus comprises or comprises a part of a: capacitor, transformer, voltage transformer, current transformer, reactor, cable system, bushing, converter, or a component and / or a combination thereof. Especially, the electrical apparatus is a liquid- filled capacitor or a cable system.

[0063] Insulating fluid or gas absorbent for use in an electrical apparatus

[0064] In another aspect, provided herein is an insulating fluid or a gas absorbent for use in an electrical apparatus, comprising a component (A) selected from the group consisting of a compound of Formula (I), where each of the groups are as defined herein above.

[0065] In an embodiment, in the compound of Formula (I): r, / TAFormula (I),

[0066] Mi and M2 are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; x and y are each independently 0 or 1; R1and R2are each independently Ce-io aryl; R1 and R2are each independently and optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen, preferably selected from Ci-io hydrocarbyl.

[0067] In some embodiments, Mi and M2 are each independently methylene. In some embodiments, at least one of R1and R2is phenyl. In some preferable embodiments, both of R1and R2are phenyl. In some embodiments, x is 0, and y is 1. In some specific embodiments, the compound of Formula (I) may include, but are not limit to the following structures:

[0068] In some embodiments, the compound of Formula (I) is benzyl benzoate, wherein x is 0 and y is 1; M2 is methylene; and both of R1and R2are unsubstituted phenyl. The compound of Formula (I) has the following formula:

[0069] The advantageous effects resulting from the selection of each portion of the compound of Formula (I) are as described above.

[0070] Low viscosity of the insulating liquid is of particular advantage for application in electrical apparatus, especially in capacitors, due to effective heat dissipation to avoid local overheating and reducing partial discharges occurrence. The intrinsic low kinematic viscosity of the compounds of Formula (I) at room temperature or higher temperatures make them favorable for use either alone in combined combination with other insulating fluids at such temperatures.

[0071] The compounds of Formula (I) may have a relatively high pouring point, which renders them poorer in low-temperature fluidity. An additional component with good flowing property, especially with good flowing property at low temperatures, is preferably added to the insulating fluid or gas absorbent according to the present disclosure. By adding an additional component with good flow properties, the application range of insulating fluid can be broadened to cover cold environments. In some embodiments, the insulating fluid or gas absorbent according to the present disclosure may further comprise a component (B) selected from the group consisting of: a compound of Formula (II) as described below, a compound of Formula (III) as described below, a mineral oil, a vegetable oil, an alkyl aromatic, a synthetic ester, a silicon oil, a polyolefin, an epoxy resin and a combination thereof.

[0072] The structures of Formula (II) and Formula (III) are as shown below:

[0073] O

[0074] R3-C — O— — (M3)p- R4Formula (II), Formula (III).

[0075] In Formula (II), M3 is a hydrocarbon chain comprising from 1 to 5 carbon atoms, such as methylene, ethylene, propylene, n-butylene, n-pentene, ethenylene, propenylene, n-butenylene and the like. In some preferable embodiments, M3 is methylene.

[0076] In Formula (II), p is 0 or 1. p as 0 means that there is no M3 in Formula (II) and R4is directly covalently bonded to the carbon atom in the ester moiety; and p as 1 means that in Formula (II), R4is covalently bonded to one end of M3 and the other end of M3 is covalently bonded to the oxygen atom in the ester moiety. In some preferable embodiments, p is 1.

[0077] In Formula (II), R4is Ce-io aryl, which is optionally substituted by one or more substituents selected from CMO hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen, preferably selected from CMO hydrocarbyl. In some preferable embodiments, R4is phenyl.

[0078] In Formula (II), R3is CM hydrocarbyl. In some preferable embodiments, R3is CM alkyl. In some more preferable embodiments, R3is propyl.

[0079] In some preferable embodiments, the compound of Formula (II) is benzyl butyrate with the following formula:

[0080] In Formula (III), M4 is a hydrocarbon chain comprising from 1 to 5 carbon atoms, such as methylene, ethylene, propylene, n-butylene, n-pentene, ethenylene, propenylene, n-butenylene and the like.

[0081] In Formula (III), q is 0 or 1. q as 0 means that there is no M4 in Formula (III) and R5is covalently directly bonded to the carbon atom in the ester moiety; and q as 1 means that in Formula (III), R5is covalently bonded to one end of M4 and the other end of M4 is covalently bonded to the carbon atom in the ester moiety.

[0082] In Formula (III), R5is Ce-io aryl, which is optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen, preferably selected from Ci-io hydrocarbyl. In some preferable embodiments, R5is phenyl.

[0083] In Formula (III), R6is C1.17 hydrocarbyl. In some preferable embodiments, R6is C1.17 alkyl.

[0084] A compound of Formula (II)-(III), particularly benzyl butyrate, has excellent solubility and compatibility with a compound of Formula(I).

[0085] In addition to good flowing properties even at low temperatures, compounds of Formula (II)-(III) have excellent dielectric and gas-absorbing properties, putting them in a suitable position as additional component. Compared to other alternative additional components with moderate or weak gas-absorbing properties (e.g., vegetable oils or aliphatic synthetic esters), the combination of compounds of Formula (I) and compounds of Formula (II)-(III) may readily achieve qualified negative gassing tendency.

[0086] As used herein, the term “mineral oil” refers to those purified by distillation from the heavy oil. Examples of the mineral oil include, but are not limited to, lubricating oil fractions obtained by atmospheric distillation and reduced pressure distillation of paraffin base crude, intermediate base crude or naphthenic base crude; paraffinic mineral oils or naphthenic mineral oils obtained, for example, by one or two or more of solvent deasphalting, solvent extraction, hydrocracking, solvent dewaxing, catalytic dewaxing, hydrogenation refining, sulfuric acid cleaning, and clay treatment. For better thermal stability, highly refined mineral oils are preferable.

[0087] As used herein, the term “vegetable oil” refers to those obtain from any part of vegetables, such as wood oil and seed oil. Examples of the vegetable oil include, but are not limited to, wood turpentine oil, China wood oil, Japanese wood oil, pine wood oil, olive oil, cacao oil, perilla oil, camellia oil, peanut oil, soybean oil, rapeseed oil, mustard oil, dehydrated castor oil, tung oil, safflower oil, linseed oil, com oil, sunflower oil, com oil, cottonseed oil, sesame oil, rice bran oil, hemp oil, evening primrose oil, palm oil, palm kernel oil, coconut oil, and the like. For excellent oxidation stability, palm oil, palm kernel oil, coconut oil is preferable. For further enhanced partial discharge characteristics, palm kernel oil, coconut oil is more preferable.

[0088] Examples of alkyl aromatics include alkyl benzene, alkyl naphthalene and aromatic hydrocarbons containing two or more aromatic rings, such as diaryl alkane, triaryl alkane and the like.

[0089] Alkyl benzenes are aromatic hydrocarbons with one or more alkyl groups bound to a benzene ring, such as decyl benzene, undecyl benzene, dodecyl benzene, tridecyl benzene, tetradecyl benzene, heptadecyl benzene, octadecyl benzene, nonadecyl benzene, icosyl benzene.

[0090] Alkyl naphthalene are aromatic hydrocarbons with one or more alkyl groups bound to a naphthalene ring, such as decylnaphthalene, undecyl naphthalene, dodecyl naphthalene, tridecyl naphthalene, tetradecyl naphthalene, heptadecyl naphthalene, octadecylnaphthalene, nonadecyl naphthalene, icosyl naphthalene.

[0091] Diaryl alkane refers to an alkyl aromatic containing two aromatic rings in the molecule. Examples of diaryl alkane include diphenylmethane, benzyl toluene, benzyl xylene, phenylsec-butyl phenyl methane, di-sec-butyl diphenylmethane, diphenylethane, phenylethyl phenyl ethane, phenyl cumyl ethane, diisopropylphenyl ethane, phenyl tolyl ethane, di-sec-butyl phenyl ethane, di-tert-butylphenyl ethane, phenyl xylyl ethane, phenyl -sec-butyl phenyl ethane, diphenyl propane, diphenyl butane and the like.

[0092] Triaryl alkane refers to an alkyl aromatic containing three aromatic rings in the molecule. Examples of triaryl alkane include dibenzyl benzene, dibenzyl toluene, dibenzyl xylene and their alkyl substituted derivatives, and the like.

[0093] Synthetic ester refers to an esterification product of acid and alcohol. The molecular structure of the synthetic ester may contain one or more ester groups. Synthetic ester may be prepared from fatty acids and fatty alcohols, or from aromatic acids and fatty alcohols, or from fatty acids and aromatic alcohols.

[0094] Synthetic ester may be phthalate, which is an esterification product of phthalic acid and alcohol. Examples of phthalate may include dinonyl phthalate, diisopropyl phthalate, diallyl phthalate, octodecyl phthalate, didecyl phthalate, diisopentyl phthalate and the like.

[0095] It should be understood that the synthetic insulating fluid as the additional component refers to any synthetic insulating fluid other than compounds of Formula (I)-(III). Particularly, the synthetic ester as the additional component refers to any synthetic ester other than compounds of Formula (I)-(III).

[0096] Silicon oil refers to linear polysiloxane that remain liquid at room temperature. Examples of silicon oil include dimethyl silicone oil, diethyl silicone oil, phenyl silicone oil, phenylmethyl silicone oil and the like.

[0097] Polyolefin herein refers to olefin polymers, which are usually in liquid state at room temperature. Examples of polyolefin may include poly-a-olefin (PAO), polyisobutene and the like.

[0098] Epoxy resin herein refers to polymers that contain more than two epoxy groups in the molecule, which are usually in liquid state at room temperature. Examples of epoxy resin may include aliphatic epoxy resin, alicyclic epoxy resin and the like.

[0099] For environmental-friendly purposes, the additional components are biodegradable or have readily biodegradable property.

[0100] An additional component (B) exhibiting exceptional low-temperature fluidity compensates for the deficiency of insufficient fluidity of the compound of Formula (I) at low temperatures. In some embodiments, the component (B) may have as a kinematic viscosity of 300 mm2 / s or less, or 250 mm2 / s or less, or 200 mm2 / s or less, or 150 mm2 / s or less, or 100 mm2 / s or less at -25°C measured in accordance with GB / T265-1988 or ISO 3104-2020. In some embodiments, the component (B) may have as a kinematic viscosity of 600 mm2 / s or less, or 550 mm2 / s or less, or 500 mm2 / s or less, or 450 mm2 / s or less, or 400 mm2 / s or less at -40°C measured in accordance with GB / T265-1988 or ISO 3104-2020. In some embodiments, the component (B) may have as a kinematic viscosity of 1500 mm2 / s or less, or 1450 mm2 / s or less, or 1400 mm2 / s or less, or 1350 mm2 / s or less, or 1300 mm2 / s or less at -50°C measured in accordance with GB / T265-1988 or ISO 3104-2020. Even if there is a high content (e.g., up to 70 wt%) of compounds of Formula (I), the inclusion of such component (B) within the insulating fluid can guarantee satisfactory low-temperature fluidity.

[0101] A suitable content of the compound of Formula (I) ensures that the insulating fluid or gas absorbent according to the present disclosure has desirable gas-absorbing properties, dielectric properties and flowing properties.

[0102] In some embodiments, based on the total weight of the component (A) and the component (B) according to the present disclosure, the content of the component (A) is 0.1-70wt%, preferably 0.1-50wt%, more preferably 0.1-30wt%, such as 0.1 wt%, 0.2 wt%, 0.5 wt%, 1.0 wt%, 2 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt% or the like as well as any subrange by any two of these values.

[0103] An overly high content of the component (A) may cause an undesirable increase on viscosity of the insulating liquid, which is not conducive to application in cold environments.

[0104] In some embodiments, based on the total weight of the component (A) and the component (B) according to the present disclosure, the content of the component (B) is 30-99.9wt%, preferably 50-99.9wt%, more preferably 70-99.9wt%, such as 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 90 wt%, 95 wt%, 99.0 wt% or the like as well as any subrange by any two of these values.

[0105] In addition to the component (A) and component (B) as described above, the insulating fluid or gas absorbent according to the present disclosure may further comprise commonly used additives. Examples of additives includes, but are not limit to an antioxidant, a decomposition inhibitor and the like. Based on the total weight of the insulating fluid or gas absorbent, the content of additives may be 10 wt% or less, preferably 5 wt% or less, more preferably 2 wt% or less, even preferably 1 wt% or less, and also may be 0 wt%.

[0106] The insulating fluid or gas absorbent according to the present disclosure may have a kinematic viscosity of 150 mm2 / s or less, preferably 100 mm2 / s or less, more preferably 50 mm2 / s or less at 20°C, e.g., 150 mm2 / s or less, or 140 mm2 / s or less, or 130 mm2 / s or less, or 120 mm2 / s or less, or 110 mm2 / s or less, or 100 mm2 / s or less, or 90 mm2 / s or less, or 80 mm2 / s or less, or 70 mm2 / s or less, or 60 mm2 / s or less, or 50 mm2 / s or less, or 40 mm2 / s or less, or 30 mm2 / s or less, or 20 mm2 / s or less, or 10 mm2 / s or less, or 5 mm2 / s or less. The kinematic viscosity may be measured in accordance with GB / T265-1988 or ISO 3104-2020.

[0107] The insulating fluid or gas absorbent according to the present disclosure may have a kinematic viscosity of 3500 mm2 / s or less, preferably 1500 mm2 / s or less, more preferably 500 mm2 / s or less at -25°C, e.g., 3500 mm2 / s or less, or 3000 mm2 / s or less, or 2000 mm2 / s or less, or 1500 mm2 / s or less, or 1400 mm2 / s or less, or 1200 mm2 / s or less, or 1000 mm2 / s or less, or 800 mm2 / s or less, or 600 mm2 / s or less, or 500 mm2 / s or less, or 200 mm2 / s or less, or 100 mm2 / s or less, or 80 mm2 / s or less, or 60 mm2 / s or less, or 40 mm2 / s or less, or 20 mm2 / s or less. The kinematic viscosity may be measured in accordance with GB / T265-1988 or ISO 3104- 2020.

[0108] The insulating fluid or gas absorbent according to the present disclosure may have a kinematic viscosity of 20000 mm2 / s or less, preferably 3000 mm2 / s or less, more preferably 1000 mm2 / s or less at -40°C, e.g., 20000 mm2 / s or less, or 15000 mm2 / s or less, or 10000 mm2 / s or less, or 5000 mm2 / s or less, or 3000 mm2 / s or less, or 2000 mm2 / s or less, or 1000 mm2 / s or less, or 800 mm2 / s or less, or 600 mm2 / s or less, or 400 mm2 / s or less, or 200 mm2 / s or less, or 100 mm2 / s or less. The kinematic viscosity may be measured in accordance with GB / T265- 1988 or ISO 3104-2020.

[0109] The insulating fluid or gas absorbent according to the present disclosure may have a kinematic viscosity of 30000 mm2 / s or less, preferably 5000 mm2 / s or less, more preferably 1500 mm2 / s or less at -50°C, e.g., 30000 mm2 / s or less, or 10000 mm2 / s or less, or 5000 mm2 / s or less, or 2000 mm2 / s or less, or 1500 mm2 / s or less, or 1000 mm2 / s or less, or 800 mm2 / s or less, or 600 mm2 / s or less, or 400 mm2 / s or less, or 200 mm2 / s or less. The kinematic viscosity may be measured in accordance with GB / T265-1988 or ISO 3104-2020.

[0110] The insulating fluid or gas absorbent according to the present disclosure has a pouring point below -50°C. The pouring point may be measured in accordance with IEC 60867-2022.

[0111] An insulating fluid or gas absorbent with a kinematic viscosity and pouring point within the above range has better cooling effect and better versatility, even in cold areas.

[0112] The insulating fluid or gas absorbent according to the present disclosure may have a gassing coefficient below -20 mm3 / min, preferably below -50 mm3 / min, more preferably below -100 mm3 / min. The gassing coefficient may be measured in accordance with IEC 60628 A (Ed.2, 1985). An insulating fluid or gas absorbent with a gassing coefficient within the above range can be used in electrical apparatus with higher gas-absorbing requirements, e.g., in a capacitor.

[0113] Electrical apparatus

[0114] In another aspect, provided herein is an electrical apparatus which comprises the insulating fluid or gas absorbent as described above.

[0115] Compared to a conventional insulating fluid, the insulating fluid or gas absorbent as described herein render the electrical apparatus better gas-absorbing properties. As a result, electrical apparatus containing the insulating fluid or gas absorbent as described herein may have better operational safety, especially the electrical apparatus involving harsh operating environment, such as medium to high voltage, high temperature or the like.

[0116] In some embodiments, the electrical apparatus comprises or comprises a part of a: capacitor, transformer, voltage transformer, current transformer, reactor, cable system, bushing, converter, or a component and / or a combination thereof.

[0117] In some embodiments, the electrical apparatus is a capacitor filled with the insulating fluid or gas absorbent as described herein. Breakdown is less likely to occur in such capacitor since it has better resistance to gassing and stability to electrical discharge.

[0118] Method for preparing electrical apparatus

[0119] In another aspect, provided herein is a method for preparing an electrical apparatus. The method herein comprises providing an electrical apparatus and filling the insulating fluid or gas absorbent as described herein into the electrical apparatus.

[0120] The insulating fluid or gas absorbent is preferably purified before being filled into the electrical apparatus to satisfy the requirements for use in electrical apparatus. Examples of the purification process include but are not limited to a clay filtration treatment or a vacuum dehydration treatment.

[0121] In some embodiments, the insulating fluid or gas absorbent has a neutralization value of 0.5 mgKOH / g or less before being filled into the electrical apparatus.

[0122] In some embodiments, the insulating fluid or gas absorbent has a water content of 200 ppm or less before being filled into the electrical apparatus.

[0123] Method for absorbing gas component

[0124] As described above, decreasing gaseous inclusions may be of great importance to prevent partial discharges. Before the application of insulating liquid to apparatus, the gases can be easily removed by conventional means, such as vacuuming. However, if an electrical apparatus has been equipped with insulating liquid, especially during operation period, it becomes more difficult to remove gases. For oxygen or water vapor, these gases can be absorbed by antioxidants or moisture absorbers, whereas the absorption of hydrogen gas or gaseous hydrocarbons remains a challenge.

[0125] The insulating fluid or gas absorbent as described herein has good excellent absorption properties for hydrogen gas and gaseous hydrocarbons and thus in another aspect, provided herein is a method for absorbing a gas component in an electrical apparatus, comprising applying the insulating fluid or gas absorbent as described above to the electrical apparatus. As used herein, “absorb a gas component” refers to a process which result in a decrease on the amount of the gas component. The insulating fluid or gas absorbent as described herein realizes the process of absorbing a gas component by contacting with the target gas component to be absorbed. In some embodiments, the gas component is generated from chemical decomposition of insulating fluids filled in electrical apparatus under the impact of electrical and thermal stresses.

[0126] Gas component may be absorbed by any means, preferably by chemical reaction. The gas components may include, but are not limited to hydrogen gas and gaseous hydrocarbons, such as methane, ethane, ethylene, acetylene, etc. The preferable gas component is hydrogen gas.

[0127] The insulating fluid or gas absorbent is preferably purified before application to the electrical apparatus to obtain a further reduction of the dielectric loss of the fluids. Examples of the purification process include but are not limited to a clay filtration treatment or a vacuum dehydration treatment.

[0128] BENEFICIAL EFFECTS

[0129] The present inventors find for the first time that a compound of Formula (I) (an aromatic synthetic ester) can be used as an ideal insulating fluid or gas absorbent. Compared to conventional insulating oils, the insulating fluid or gas absorbent according to the present disclosure shows better gas-absorbing properties. The gas-absorbing properties of a system can also be effectively improved with the addition of an even a small amount of a gas absorbent as described herein. Additional components may be included in the present insulating fluid to enhance the flow properties of the fluid, thereby increasing versatility. In addition, the present insulating fluid or gas absorbent is of good commercial applicability due to low cost.

[0130] EXAMPLES

[0131] The solution of the present disclosure will be further described in detail below in conjunction with specific examples.

[0132] It should be noted that the following examples are only examples for clearly explaining the technical solution of the present disclosure and are not limitations of the present disclosure. For an ordinary technical person in the art, other changes or modifications in different forms can be made on the basis of the above description, and it is unnecessary and impossible to exhaust all the embodiments herein and the obvious changes or modifications derived therefrom are still within the protection scope of the present disclosure. Unless otherwise specified, the instruments, equipment and reagent materials used herein are all commercially available. Materials

[0133] Benzyl benzoate: CAS No. 120-51-4, purchased from Wuxi Yatai Joint Chemicals, China.

[0134] Benzyl butyrate: CAS No. 103-37-7, purchased from Wanghua (Shandong) chemical technology Co., Ltd, China.

[0135] M / DBT (Jarylec C101): containing monobenzyl toluene and dibenzyl toluene, purchased from ARKEMA, France.

[0136] SAS-fluid: containing monobenzyl toluene and diphenyl ethane, purchased from Mitsubishi International GmbH, Germany.

[0137] The detailed information about formula and cost of Examples and Comparative Examples (typical insulating fluids presently used in capacitor products) are shown in Table 1 and 2.

[0138] Table 1 Table 2

[0139] Gassing Tendency Results

[0140] Table 3 and 4 showed the test results of gassing coefficient of Examples and Comparative Examples. Table 3

[0141] Compared to Comparative Examples la-b, Examples la-d had a stronger negative gassing tendency. Specifically, Comparative Examples la-b showed gassing coefficients of about -143 to -123 mm3 / min while Examples la-d showed superior gassing coefficients (about -252 to -157 mm3 / min), indicating a stronger negative gassing tendency compared to the Comparative Examples.

[0142] In addition, it can be seen that the gas-absorbing abilities of the Examples la-d were significantly improved with the increase of addition contents of benzyl benzoate, indicating that compounds of Formula (I) are particularly well-suited for use as a gas absorbent with ultrastrong negative gassing tendency.

[0143] Table 4

[0144] The testing method for gassing coefficient in Table 4 is identical to that employed in Table 3. It can be seen from Table 4 that the addition of benzyl benzoate significantly increased the gas-absorbing properties of various typical insulating fluids, including mineral oil, synthetic ester, vegetable oil (natural ester), synthetic aromatic hydrocarbon and silicone fluid.

[0145] Flowing Properties Results

[0146] Pouring point test: conducted in at CEMT, Guilin (IEC 60867-2022).

[0147] Kinematic viscosity test: performed at HAECKEL, Henan and LONGHUA, Shanghai (GB / T265-1988).

[0148] The testing results of flowing properties for Examples and Comparative Examples were summarized in Table 5 and 6. Table 5

[0149] It can be seen from Table 4 that Examples la-d had a much lower kinematic viscosity at room temperature (20°C) than Comparative Examples la-b. According to Examples la-d, the addition of benzyl butyrate had effectively reduced the kinematic viscosity at low temperatures. Such low viscosity is of particular advantage for application in capacitors due to effective heat dissipation to avoid local overheating and reducing partial discharges occurrence.

[0150] Table 6

[0151] It can be seen from Table 6 that benzyl benzoate reduced the kinematic viscosity of various insulating fluids typically used in power and electrical apparatus at room temperature or higher temperatures, due to the low intrinsic kinematic viscosity of benzyl benzoate.

[0152] Dielectric Properties Results

[0153] Table 7 and 8 listed the measurement results of Examples and Comparative Examples.

[0154] Table 7 As shown in Table 7, it was found that Examples la-d had a comparable breakdown voltage (with 2.5 mm electrode gap) and higher permittivity (at 50Hz and 100°C) than Comparative Examples la-b. In capacitor products, increased permittivity enables a higher energy density to be achieved, diminishing the required quantity of insulating liquids and lowering costs.

[0155] Table 8

[0156] It can be seen from Table 8 that mixing benzyl benzoate with other typical insulating fluids can obtain comparable or even higher breakdown strength for the fluid system, and can fulfill the requirements on dielectric performance for the electrical apparatus such as power capacitors.

[0157] Although the specific embodiments according to the present disclosure have been described above, it should be understood by those skilled in the art that this is by way of example only and the protection scope of the present disclosure is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principle and essence of the present disclosure, but these changes and modifications all fall within the protection scope of the present disclosure.

Claims

CLAIMS1. Use of a compound of Formula (I) as an insulating fluid or a gas absorbent in an electrical apparatus,„ Formula (I) whereinMi and M2 are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; x and y are each independently 0 or 1 ;R1and R2are each independently Ce-io aryl;R1and R2are each independently and optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen.

2. The use according to claim 1, whereinMi and M2 are each independently methylene; and / or at least one of R1and R2is phenyl, preferably both of R1and R2are phenyl; and / or x is 0, and y is 1.

3. The use according to claim 1 or 2, wherein the compound of Formula (I) has the following formula:

4. An insulating fluid or a gas absorbent for use in an electrical apparatus, comprising a component (A) selected from the group consisting of a compound of Formula (I):Formula (I) whereinMi and M2 are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; x and y are each independently 0 or 1 ;R1and R2are each independently Ce-io aryl;R1and R2are each independently and optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen.

5. The insulating fluid or gas absorbent according to claim 4, wherein in Formula (I),Mi and M2 are each independently methylene; and / or at least one of R1and R2is phenyl, preferably both of R1and R2are phenyl; and / or x is 0, and y is 1.

6. The insulating fluid or gas absorbent according to claim 4 or 5, wherein the compound of Formula (I) has the following formula:

7. The insulating fluid or gas absorbent according to any one of claims 4-6, further comprising a component (B) selected from the group consisting of: a compound of Formula (II), a compound of Formula (III), a mineral oil, a vegetable oil, an alkyl aromatic, a synthetic ester, a silicon oil, a polyolefin, an epoxy resin and a combination thereof, oR3— C — O — (M3)p- R4Formula (II)Formula (III) whereinM3 and M4 are each independently a hydrocarbon chain comprising from 1 to 5 carbon atoms; p and q are each independently 0 or 1, preferably 1;R3is Ci-4 hydrocarbyl, preferably C1.4 alkyl, more preferably propyl;R4is Ce-io aryl, which is optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, hydroxyl, carboxyl, amino, nitro and halogen, preferably, R4is phenyl;R5is Ce-io aryl, which is optionally substituted by one or more substituents selected from Ci-io hydrocarbyl, preferably, R5is phenyl;R6is Ci-i7 hydrocarbyl, preferably C1.17 alkyl.

8. The insulating fluid or gas absorbent according to claim 7, wherein the compound of Formula (II) has the following formula:

9. The insulating fluid or gas absorbent according to claim 7, wherein the component (B) has as a kinematic viscosity of 300 mm2 / s or less at -25°C measured in accordance with GB / T265-1988 or ISO 3104-2020; and / or the component (B) has as a kinematic viscosity of 600 mm2 / s or less at -40°C measured in accordance with GB / T265-1988 or ISO 3104-2020; and / or the component (B) has as a kinematic viscosity of 1500 mm2 / s or less at -50°C measured in accordance with GB / T265-1988 or ISO 3104-2020.

10. The insulating fluid or gas absorbent according to any one of claims 4-9, wherein based on the total weight of the component (A) and the component (B), the content of the component (A) is 0.1-70wt%, preferably 0.1-50wt%, more preferably 0.1-30wt%.

11. The insulating fluid or gas absorbent according to any one of claims 4-9, wherein based on the total weight of the component (A) and the component (B), the content of the component (B) is 30-99.9wt%, preferably 50-99.9wt%, more preferably 70-99.9wt%.

12. The insulating fluid or gas absorbent according to any one of claims 4-11, wherein the insulating fluid or gas absorbent has a kinematic viscosity of 150 mm2 / s or less, preferably 100 mm2 / s or less, more preferably 50 mm2 / s or less at 20°C measured in accordance with GB / T265-1988 or ISO 3104-2020; and / or the insulating fluid or gas absorbent has a kinematic viscosity of 3500 mm2 / s or less, preferably 1500 mm2 / s or less, more preferably 500 mm2 / s or less at -25°C measured in accordance with GB / T265-1988 or ISO 3104-2020; and / or the insulating fluid or gas absorbent has a kinematic viscosity of 20000 mm2 / s or less, preferably 3000 mm2 / s or less, more preferably 1000 mm2 / s or less at -40°C measured in accordance with GB / T265-1988 or ISO 3104-2020; and / or the insulating fluid or gas absorbent has a kinematic viscosity of 30000 mm2 / s or less,preferably 5000 mm2 / s or less, more preferably 1500 mm2 / s or less at -50°C measured in accordance with GB / T265-1988 or ISO 3104-2020.

13. The insulating fluid or gas absorbent according to any one of claims 4-11, wherein the insulating fluid or gas absorbent has a pouring point of below -50°C measured in accordance with IEC 60867-2022.

14. The insulating fluid or gas absorbent according to any one of claims 4-11, wherein the insulating fluid or gas absorbent has a gassing coefficient of below -20 mm3 / min, preferably below -50 mm3 / min, more preferably below -100 mm3 / min measured in accordance with IEC 60628A (Ed.2, 1985).

15. An electrical apparatus, comprising the insulating fluid or gas absorbent according to any one of claims 4-14.

16. A method for preparing an electrical apparatus, comprising providing an electrical apparatus, and filling the insulating fluid or gas absorbent according to any one of claims 4-14 into the electrical apparatus.

17. The method according to claim 16, wherein the insulating fluid or gas absorbent is purified before being filled into the electrical apparatus.

18. The method according to claim 16 or 17, wherein the insulating fluid or gas absorbent has a neutralization value of 0.5 mgKOH / g or less before being filled into to the electrical apparatus; and / or the insulating fluid or gas absorbent has a water content of 200 ppm or less before being filled into the electrical apparatus.

19. A method for absorbing a gas component in an electrical apparatus, comprising applying the insulating fluid or gas absorbent according to any one of claims 4-14 to the electrical apparatus.

20. The method according to claim 19, wherein the gas component comprises hydrogen.

21. The use according to any one of claims 1-3, the insulating fluid or gas absorbentaccording to any one of claims 4-14, the electrical apparatus according to claim 15 and the method according to any one of claims 16-20, wherein the electrical apparatus comprises or comprises a part of a: capacitor, transformer, voltage transformer, current transformer, reactor, cable system, bushing, converter, or a component and / or a combination thereof.

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