US2075410A - Impregnated dielectric materials - Google Patents
Impregnated dielectric materials Download PDFInfo
- Publication number
- US2075410A US2075410A US2075410DA US2075410A US 2075410 A US2075410 A US 2075410A US 2075410D A US2075410D A US 2075410DA US 2075410 A US2075410 A US 2075410A
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- US
- United States
- Prior art keywords
- viscosity value
- impregnated
- mixture
- seconds redwood
- hydrocarbon
- Prior art date
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- Expired - Lifetime
Links
- 239000003989 dielectric material Substances 0.000 title description 42
- 240000005020 Acaciella glauca Species 0.000 description 76
- 235000003499 redwood Nutrition 0.000 description 76
- 239000000203 mixture Substances 0.000 description 66
- 150000002430 hydrocarbons Chemical class 0.000 description 48
- 239000004215 Carbon black (E152) Substances 0.000 description 46
- 239000003921 oil Substances 0.000 description 30
- 230000002745 absorbent Effects 0.000 description 20
- 239000002250 absorbent Substances 0.000 description 20
- 239000002657 fibrous material Substances 0.000 description 20
- 239000002480 mineral oil Substances 0.000 description 20
- 235000010446 mineral oil Nutrition 0.000 description 20
- VSCWAEJMTAWNJL-UHFFFAOYSA-K Aluminium chloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 8
- 239000004020 conductor Substances 0.000 description 6
- 230000003647 oxidation Effects 0.000 description 6
- 238000007254 oxidation reaction Methods 0.000 description 6
- 239000007788 liquid Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000003208 petroleum Substances 0.000 description 4
- 238000006116 polymerization reaction Methods 0.000 description 4
- 230000000379 polymerizing Effects 0.000 description 4
- 230000001681 protective Effects 0.000 description 4
- RAHZWNYVWXNFOC-UHFFFAOYSA-N sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 4
- 241000283690 Bos taurus Species 0.000 description 2
- 240000000491 Corchorus aestuans Species 0.000 description 2
- 235000011777 Corchorus aestuans Nutrition 0.000 description 2
- 235000010862 Corchorus capsularis Nutrition 0.000 description 2
- 238000010306 acid treatment Methods 0.000 description 2
- 239000003513 alkali Substances 0.000 description 2
- 238000004061 bleaching Methods 0.000 description 2
- 230000015556 catabolic process Effects 0.000 description 2
- 235000013351 cheese Nutrition 0.000 description 2
- 150000001805 chlorine compounds Chemical class 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 239000010779 crude oil Substances 0.000 description 2
- 239000000295 fuel oil Substances 0.000 description 2
- 239000008240 homogeneous mixture Substances 0.000 description 2
- 238000005470 impregnation Methods 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000002904 solvent Substances 0.000 description 2
- 235000010269 sulphur dioxide Nutrition 0.000 description 2
- 239000004291 sulphur dioxide Substances 0.000 description 2
- 238000005292 vacuum distillation Methods 0.000 description 2
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/02—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances
- H01B3/08—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances quartz; glass; glass wool; slag wool; vitreous enamels
- H01B3/082—Wires with glass or glass wool
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
- H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
- H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
- H01B3/20—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances liquids, e.g. oils
- H01B3/22—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances liquids, e.g. oils hydrocarbons
Definitions
- This invention consists in improvements in or relating to impregnated dielectric materials suitable for cable wrappings or interleaving sheets for condensers or for like purposes.
- An object 5 of the invention is to produce an insulating material having high resistance to oxidation and good dielectric properties.
- hydrocarbons of very high viscosity may be obtained by polymerizing suitable petroleum fractions in the presence of certain metallic chlorides, e. g. aluminium chloride.
- an impregnated dielectric material comprises paper or like absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between the limits 2500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value less than 200 seconds Redwood at 200 F.
- the mixture is a homogeneous mixture of the oils and should have a viscosity value of between 1500 and 3000 seconds Redwood at 140 F.
- the high viscos- 35 ity hydrocarbon is refined, before mixing, by any suitable refining process, for example by treatment with selective solvents (e. g. the Duosol process) or with liquid sulphur dioxide or by acid treatment or alkali treatment or by bleaching 40 with earths or by high vacuum distillation.
- the dielectric material under electric stress which commonly results when a saturated parafiinic or olefinic oil is em- 45 ployed
- the mineral oil which should preferably have a viscosity value between 50 and 200 seconds Redwood at 200 F
- a pure, highly refined naphthenic oile g. the Sun Oil Companys 50 XX oil.
- the mixture comprises 30% of said highly viscous hydrocarbon.
- the invention includes an electric cable wrapped with paper or like absorbent fibrous material (e. g. jute) impregnated with the mix- 55 ture described.
- absorbent fibrous material e. g. jute
- the impregnation is carried out during or after the wrapping steps.
- a high viscosity hydrocarbon was prepared by polymerizing the heavy ends from a petrol produced by cracking crude oil, in the presence of anhydrous aluminium chloride, the polymerization being carried out in the vapour phase, and to the full extent so as to give the maximum viscosity.
- the high viscosity product so obtained was mixed with highly refined naphthenic oil in the proportions of one part of the product to two parts of the oil. This mixture has a viscosity of 2,500 seconds Redwood at 60 C. so being in accordance with normal European practice, and was employed to impregnate a paper-wrapped electric cable.
- Any suitable petroleum fraction e. g. any frac" tion between petrol and fuel oil
- the polymerization may be carried out in either the liquid or vapour phase.
- a cable wrapped with paper impregnated with the mixture described has a particularly high dielectric resistance, and re sistance to oxidation as well as low power Iactor losses and that'the cable may be operated at temperatures up to 20 to C. higher than is the usual practice without causing thermal instability and subsequent breakdown.
- the size of the cable and consequently the cost may therefore be de 39 creased without sacrifice of safety.
- the drawing is a diagrammatic representation of an electric cable provided with an insulating covering formed from a strip of absorbent fibrous material wrapped around the electric conductor and impregnated either before or during the wrapping operation with the hydrocarbon mixture hereinbefore described.
- the cable may be provided with the usual protective sheath of any suitable material.
- the invention includes the use, as an impregnating medium for dielectric materials, of a mixture of a hydrocarbon of high viscosity and a a comparatively low viscosity mineral oil.
- An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F., with a less viscous 59 mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
- An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon
- An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
- An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value of less than 200 seconds Redwood at 200 F.
- An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a less viscous mineral oil having a viscosity value between 50 and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F. said mixture containing about 30% of said highly viscous hydrocarbon.
- An impregnated dielectric material comprising paper impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at zoo F. with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
- An impregnated dielectric material comprising paper impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value between 50 and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F,
- An impregnated dielectric material comprising paper impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value between and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at F. said mixture containing about 30% of said highly viscous refined hydrocarbon.
- An impregnated dielectric material for an electric conductor comprising a strip of absorbent fibrous material wrapped around said conductor and impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value between 50 and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F., said mixture containing about 30% of said highly viscous refined hydrocarbon.
- An impregnating medium for dielectric materials comprising a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
- An impregnating medium for dielectric materials comprising a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil, having a viscosity value of less than 200 seconds Redwood at 200 F.
- An impregnating medium for dielectric materials comprising a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil, having a viscosity value between 50 and 200 seconds Redwood at 200 F. said mixture containing about 30% of said highly viscous hydrocarbon and having a viscosity value between 1500 and 3000 seconds Redwood at 140 F.
- An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 1500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
Description
March 30, A w TH M ON IMPREGNATED DIELECTRIC MATERIALS AND IMPREGNATING COMPOSITIONS Filed Dec. 4, 1955 PROTECTIVE SH EATH ELECTRIC cow DUCTOR I MPR EGNATE D DIELECTRIC MATERIAL 171 De 71 to r: MM 012% Mm,
Patented Mar. 30, 1937 IMPREGNATED DIELECTRIC MATERIALS AND IMPREGNATING COMPOSITIONS Archibald Walter Thompson, Bromley, England Application December 4, 1935, Serial No. 52,885 In Great Britain December 13, 1934 13 Claims.
This invention consists in improvements in or relating to impregnated dielectric materials suitable for cable wrappings or interleaving sheets for condensers or for like purposes. An object 5 of the invention is to produce an insulating material having high resistance to oxidation and good dielectric properties.
It is customary to impregnate paper or like wrappings for electric cables with oil but difll- 10 culties arise in practice because the oil is apt to drain away from the paper or the like. Mixtures of oil and resin having a high viscosity are commonly employed to impregnate paper or like wrappings with a View to obviating draining but 15 such mixtures are susceptible to oxidation and it is found difficult to obtain sufiiciently good dielectric properties.
It has now been discovered that hydrocarbons of very high viscosity (e. g. 2000 to 3000 seconds Redwood at 200 F.) may be obtained by polymerizing suitable petroleum fractions in the presence of certain metallic chlorides, e. g. aluminium chloride.
According to this invention an impregnated dielectric material comprises paper or like absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between the limits 2500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value less than 200 seconds Redwood at 200 F. The mixture is a homogeneous mixture of the oils and should have a viscosity value of between 1500 and 3000 seconds Redwood at 140 F. Preferably the high viscos- 35 ity hydrocarbon is refined, before mixing, by any suitable refining process, for example by treatment with selective solvents (e. g. the Duosol process) or with liquid sulphur dioxide or by acid treatment or alkali treatment or by bleaching 40 with earths or by high vacuum distillation.
In order to reduce the likelihood of gassing or cheese" formationin the dielectric material under electric stress (which commonly results when a saturated parafiinic or olefinic oil is em- 45 ployed) it is a further feature of the invention to use, as the mineral oil (which should preferably have a viscosity value between 50 and 200 seconds Redwood at 200 F), a pure, highly refined naphthenic oile. g. the Sun Oil Companys 50 XX oil. Preferably the mixture comprises 30% of said highly viscous hydrocarbon.
The invention includes an electric cable wrapped with paper or like absorbent fibrous material (e. g. jute) impregnated with the mix- 55 ture described. Preferably the impregnation is carried out during or after the wrapping steps.
In one specific example of the invention which will now be described, a high viscosity hydrocarbon was prepared by polymerizing the heavy ends from a petrol produced by cracking crude oil, in the presence of anhydrous aluminium chloride, the polymerization being carried out in the vapour phase, and to the full extent so as to give the maximum viscosity. The high viscosity product so obtained was mixed with highly refined naphthenic oil in the proportions of one part of the product to two parts of the oil. This mixture has a viscosity of 2,500 seconds Redwood at 60 C. so being in accordance with normal European practice, and was employed to impregnate a paper-wrapped electric cable.
Any suitable petroleum fraction (e. g. any frac" tion between petrol and fuel oil) may be polymerized to give the high viscosity product and the polymerization may be carried out in either the liquid or vapour phase.
It is found that a cable wrapped with paper impregnated with the mixture described has a particularly high dielectric resistance, and re sistance to oxidation as well as low power Iactor losses and that'the cable may be operated at temperatures up to 20 to C. higher than is the usual practice without causing thermal instability and subsequent breakdown. The size of the cable and consequently the cost may therefore be de 39 creased without sacrifice of safety.
The drawing is a diagrammatic representation of an electric cable provided with an insulating covering formed from a strip of absorbent fibrous material wrapped around the electric conductor and impregnated either before or during the wrapping operation with the hydrocarbon mixture hereinbefore described. The cable may be provided with the usual protective sheath of any suitable material.
The invention includes the use, as an impregnating medium for dielectric materials, of a mixture of a hydrocarbon of high viscosity and a a comparatively low viscosity mineral oil.
I claim:
1. An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F., with a less viscous 59 mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
2. An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon,
having a viscosity value between 2500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value between 50 and 200 seconds Redwood at 200 F., which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F.
3. An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
4. An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value of less than 200 seconds Redwood at 200 F.
5. An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a less viscous mineral oil having a viscosity value between 50 and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F. said mixture containing about 30% of said highly viscous hydrocarbon.
6. An impregnated dielectric material comprising paper impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at zoo F. with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
7. An impregnated dielectric material comprising paper impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value between 50 and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F,
8. An impregnated dielectric material comprising paper impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value between and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at F. said mixture containing about 30% of said highly viscous refined hydrocarbon.
9. An impregnated dielectric material for an electric conductor comprising a strip of absorbent fibrous material wrapped around said conductor and impregnated with a mixture of a highly viscous refined hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil having a viscosity value between 50 and 200 seconds Redwood at 200 F. which mixture has a viscosity value between 1500 and 3000 seconds Redwood at 140 F., said mixture containing about 30% of said highly viscous refined hydrocarbon.
10. An impregnating medium for dielectric materials comprising a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
11. An impregnating medium for dielectric materials comprising a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil, having a viscosity value of less than 200 seconds Redwood at 200 F.
12. An impregnating medium for dielectric materials comprising a mixture of a highly viscous hydrocarbon, having a viscosity value between 2500 and 3000 seconds Redwood at 200 F. with a highly refined naphthenic oil, having a viscosity value between 50 and 200 seconds Redwood at 200 F. said mixture containing about 30% of said highly viscous hydrocarbon and having a viscosity value between 1500 and 3000 seconds Redwood at 140 F.
13. An impregnated dielectric material comprising an absorbent fibrous material impregnated with a mixture of a highly viscous hydrocarbon, having a viscosity value between 1500 and 3000 seconds Redwood at 200 F., with a less viscous mineral oil having a viscosity value of less than 200 seconds Redwood at 200 F.
ARCI-IIBALD WALTER THOMPSON.
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2075410A true US2075410A (en) | 1937-03-30 |
Family
ID=3428596
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US2075410D Expired - Lifetime US2075410A (en) | Impregnated dielectric materials |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2075410A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2535690A (en) * | 1947-08-02 | 1950-12-26 | Gen Electric | Fibrous dielectric compositions |
| US2586345A (en) * | 1945-01-18 | 1952-02-19 | British Insulated Callenders | Electric cable having a nonmigratory insulating compound |
| US3132083A (en) * | 1958-10-02 | 1964-05-05 | Sinclair Research Inc | Fuel oil composition |
| US5049257A (en) * | 1987-07-17 | 1991-09-17 | Sodick Co., Ltd. | Fluid for electrical discharge machining |
-
0
- US US2075410D patent/US2075410A/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2586345A (en) * | 1945-01-18 | 1952-02-19 | British Insulated Callenders | Electric cable having a nonmigratory insulating compound |
| US2535690A (en) * | 1947-08-02 | 1950-12-26 | Gen Electric | Fibrous dielectric compositions |
| US3132083A (en) * | 1958-10-02 | 1964-05-05 | Sinclair Research Inc | Fuel oil composition |
| US5049257A (en) * | 1987-07-17 | 1991-09-17 | Sodick Co., Ltd. | Fluid for electrical discharge machining |
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