NO155618B - ELECTRIC ISOLATOR WITH GLASS DIELECTRIC AND PROCEDURE FOR ITS MANUFACTURING. - Google Patents
ELECTRIC ISOLATOR WITH GLASS DIELECTRIC AND PROCEDURE FOR ITS MANUFACTURING. Download PDFInfo
- Publication number
- NO155618B NO155618B NO823548A NO823548A NO155618B NO 155618 B NO155618 B NO 155618B NO 823548 A NO823548 A NO 823548A NO 823548 A NO823548 A NO 823548A NO 155618 B NO155618 B NO 155618B
- Authority
- NO
- Norway
- Prior art keywords
- mpa
- peak value
- chemical
- dielectric material
- temperature
- Prior art date
Links
- 239000011521 glass Substances 0.000 title claims description 10
- 238000000034 method Methods 0.000 title claims description 8
- 238000004519 manufacturing process Methods 0.000 title claims description 4
- 239000000126 substance Substances 0.000 claims description 20
- 239000003989 dielectric material Substances 0.000 claims description 18
- 230000006835 compression Effects 0.000 claims description 9
- 238000007906 compression Methods 0.000 claims description 9
- 239000012212 insulator Substances 0.000 claims description 7
- 239000000203 mixture Substances 0.000 claims description 7
- 229920002472 Starch Polymers 0.000 claims description 5
- 229910052783 alkali metal Inorganic materials 0.000 claims description 5
- -1 alkali metal salts Chemical class 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 5
- 239000000615 nonconductor Substances 0.000 claims description 5
- 235000019698 starch Nutrition 0.000 claims description 5
- 239000008107 starch Substances 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 229910000396 dipotassium phosphate Inorganic materials 0.000 claims description 4
- 238000001035 drying Methods 0.000 claims description 4
- 230000005684 electric field Effects 0.000 claims description 3
- 239000005361 soda-lime glass Substances 0.000 claims description 3
- 238000005342 ion exchange Methods 0.000 description 6
- 238000001723 curing Methods 0.000 description 5
- VWDWKYIASSYTQR-UHFFFAOYSA-N sodium nitrate Chemical compound [Na+].[O-][N+]([O-])=O VWDWKYIASSYTQR-UHFFFAOYSA-N 0.000 description 4
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- 238000001029 thermal curing Methods 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- 239000011230 binding agent Substances 0.000 description 2
- 238000007654 immersion Methods 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- IIPYXGDZVMZOAP-UHFFFAOYSA-N lithium nitrate Chemical compound [Li+].[O-][N+]([O-])=O IIPYXGDZVMZOAP-UHFFFAOYSA-N 0.000 description 2
- 235000010344 sodium nitrate Nutrition 0.000 description 2
- 239000004317 sodium nitrate Substances 0.000 description 2
- 159000000000 sodium salts Chemical class 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- XAEFZNCEHLXOMS-UHFFFAOYSA-M potassium benzoate Chemical compound [K+].[O-]C(=O)C1=CC=CC=C1 XAEFZNCEHLXOMS-UHFFFAOYSA-M 0.000 description 1
- 229910001414 potassium ion Inorganic materials 0.000 description 1
- 229910001415 sodium ion Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C21/00—Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Glass Compositions (AREA)
- Inorganic Insulating Materials (AREA)
- Surface Treatment Of Glass (AREA)
- Organic Insulating Materials (AREA)
Description
Foreliggende oppfinnelse vedrører en elektrisk isolator omfattende et dielektrikum av sodakalkglasstypen,og det særegne ved oppfinnelsen er at den er oppnådd ved kjemisk herding slik at det frembringes overflatekompresjon med en toppverdi over 100 MPa og sentral strekkspenning med en toppverdi under 10 MPa ved at materialet eller en del derav ved vanlig temperatur er dekket med en oppløsning inneholdende alkalimetallsalter, etterfulgt av tørking av belegget eller deler derav og oppvarming i flere timer ved en temperatur mellom 300 og 500°C. The present invention relates to an electrical insulator comprising a dielectric of the soda-lime glass type, and the peculiarity of the invention is that it has been achieved by chemical hardening so that surface compression with a peak value above 100 MPa and central tensile stress with a peak value below 10 MPa is produced by the material or a part of it at normal temperature is covered with a solution containing alkali metal salts, followed by drying the coating or parts thereof and heating for several hours at a temperature between 300 and 500°C.
Oppfinnelsen vedrører også en fremgangsmåte for fremstilling av den elektriske isolator, og det særegne ved fremgangsmåten i henhold til oppfinnelsen ezfet isolatorens overflate underkastes kjemisk herding slik at det frembringes overflatekompresjon med toppverdi over 100 MPa og sentral strekkspenning med en toppverdi under 10 MPa ved at materialet eller en del derav ved vanlig temperatur dekkes med en opp-løsning inneholdende alkalimetallsalter hvoretter det påførte belegg eller deler derav tørkes og oppvarmes i flere timer ved en temperatur mellom 300 og 500°C. The invention also relates to a method for producing the electrical insulator, and the peculiarity of the method according to the invention is that the surface of the insulator is subjected to chemical hardening so that surface compression with a peak value above 100 MPa and central tensile stress with a peak value below 10 MPa is produced by the material or a part of it at normal temperature is covered with a solution containing alkali metal salts, after which the applied coating or parts of it are dried and heated for several hours at a temperature between 300 and 500°C.
Disse og andre trekk ved oppfinnelsen fremgår av patentkrav-ene. These and other features of the invention appear in the patent claims.
Konvensjonelle glass-dielektrium-materialer underkastes termisk herding slik at de fremviser høy overflatekompresjon og høyt sentralt strekk. Dette resulterer i at det dielektriske material har en mye høyere mekanisk styrke enn spenningsfritt glass, og spesielt høy strekk-styrke. Det iakttas imidlertid at under visse forhold, som f.eks. kraftig slagpåvirkning, medfører forekomsten av høye indre strekk-spenninger ofte total desintegrasjon av det dielektriske material. Dette påvirker ikke i særlig grad eller i farlig grad den mekaniske styrke av den resterende del av isolatoren, men reduserer feltspredningen i luft tilsvarende avstand-en mellom elektrodene. Conventional glass-dielectric materials are subjected to thermal curing so that they exhibit high surface compression and high central tension. This results in the dielectric material having a much higher mechanical strength than stress-free glass, and particularly high tensile strength. However, it is observed that under certain conditions, such as e.g. strong impact, the occurrence of high internal tensile stresses often results in total disintegration of the dielectric material. This does not particularly or dangerously affect the mechanical strength of the remaining part of the insulator, but reduces the field spread in air corresponding to the distance between the electrodes.
Den foreliggende oppfinnelse tar sikte på å overvinne denne ulempe og tilveiebringe en isolator med et isolerende di-elektrisk material med forbedret slagfasthet. The present invention aims to overcome this disadvantage and provide an insulator with an insulating dielectric material with improved impact resistance.
De angitte verdier for overflatekompresjon og sentral strekkspenning må oppnås spesielt i de kritiske punkter på isolatoren som sannsynlig vil bli utsatt for de mekaniske på-kjenninger . The stated values for surface compression and central tensile stress must be achieved especially in the critical points on the insulator that are likely to be exposed to the mechanical stresses.
Variasjoner i utførelsen er medomfattet. F.eks. kan glasset før den kjemiske herding behandles på forhånd, slik at det får sin.overflatesammensetning modifisert til å akselerere ionebytting under den kjemiske herding. Før den kjemiske herding må det da foretas en spenningsutjevning. Variations in execution are included. E.g. before the chemical hardening, the glass can be pre-treated so that its surface composition is modified to accelerate ion exchange during the chemical hardening. Before the chemical hardening, a voltage equalization must then be carried out.
Et elektrisk felt kan også utøves under den kjemiske herding for å frembringe en "elektrovandrings-effekt" . An electric field can also be applied during the chemical cure to produce an "electromigration effect".
Ved oppfinnelsen frembringes et dielektrisk material for bruk som en elektrisk isolator, hvor overflatekompresjonen i de behandlede områder oppnås bare i en dybde på 20 til 100 pm. De områder som behandles er dem som påkjennes sterk- The invention provides a dielectric material for use as an electrical insulator, where the surface compression in the treated areas is achieved only at a depth of 20 to 100 pm. The areas that are treated are those that are strongly stressed
est mekanisk, i nivå med isolatortoppen, f.eks. Det kan være enklere å behandle det dielektriske material i sin helhet. est mechanically, at the level of the insulator top, e.g. It may be easier to process the dielectric material in its entirety.
Når et dielektrisk material av denne type mottar et slag i de behandlede områder, opptrer sprekker som går videre inn i tykkelsen av materialet, men der er ingen fullstendig des-integrering av dette. Dette resulterer i en overslagsspenn-ing som er høyere enn for en desintegrert del av isolatoren. When a dielectric material of this type receives a blow in the treated areas, cracks appear which continue into the thickness of the material, but there is no complete disintegration thereof. This results in a flashover voltage that is higher than for a disintegrated part of the insulator.
Andre formål og fordeler vil fremgå av den følgende beskriv-else av et eksempel i samsvar med oppfinnelsen, sett i for-bindelse med den vedføyde tegning. Other purposes and advantages will be apparent from the following description of an example in accordance with the invention, seen in connection with the attached drawing.
Fig. 1 og 2 viser fordelingen av spenninger i MegaPascal (MPa) i de to prøver A og B av et soda-kalkglass med gjennom- Figs 1 and 2 show the distribution of stresses in MegaPascal (MPa) in the two samples A and B of a soda-lime glass with through-
snittlig tykkelse 10 mm. average thickness 10 mm.
Prøve A ble underkastet termisk herding i samsvar med tidligere kjent teknikk. Prøven B ble underkastet kjemisk herding i samsvar med oppfinnelsen. Sample A was subjected to thermal curing in accordance with prior art. Sample B was subjected to chemical curing in accordance with the invention.
Det sees at prøve A, underkastet termisk herding, viser kompresjonsspenninger til en dybe av omtrent 2 mm. Toppverdien av disse spenninger er omtrent 250 MPa. Der er også betraktelig sentral strekkspenning idet toppverdien av disse spenninger er omtrent 100 MPa. It is seen that sample A, subjected to thermal curing, shows compressive stresses to a depth of approximately 2 mm. The peak value of these stresses is approximately 250 MPa. There is also considerable central tensile stress, as the peak value of these stresses is approximately 100 MPa.
Prøve B ble i samsvar med oppfinnelsen underkastet kjemisk herding under følgende betingelser: Den spenningsutjevnede prøve ble neddykket ved vanlig temperatur i en oppløsning med følgende sammensetning: H20 : 11% In accordance with the invention, sample B was subjected to chemical hardening under the following conditions: The stress equalized sample was immersed at normal temperature in a solution with the following composition: H20: 11%
Stivelse : 3% Starch : 3%
KN03 : 8% KN03 : 8%
K2HP04 : 12% K2HP04 : 12%
Denne oppløsning fuktet glasset meget grundig og det dielektriske material var fullstendig dekket med en væskefilm med styrbar viskositet. Etter tørkingen ble varmebehandling gjennomført ved oppvarming i 8 timer ved en temperatur på 500°C. This solution wetted the glass very thoroughly and the dielectric material was completely covered with a liquid film of controllable viscosity. After drying, heat treatment was carried out by heating for 8 hours at a temperature of 500°C.
Kurve B viser fordelingen av strekkspenning og trykkspenning i di-elektrisk material B. Curve B shows the distribution of tensile stress and compressive stress in dielectric material B.
Den maksimale overflatekompresjon var omtrent 200 MPa mens den maksimale sentrale strekkspenning var mye lavere enn 10 MPa. Tykkelsen av laget under kompresjon var omtrent 100 Denne størrelse av sentral strekkspenning er til-strekkelig lav til å unngå desintegrasjon av prøven som følge The maximum surface compression was about 200 MPa while the maximum central tensile stress was much lower than 10 MPa. The thickness of the layer under compression was approximately 100 This magnitude of central tensile stress is sufficiently low to avoid disintegration of the sample as a result
av kraftig slagpåvirkning. of strong impact.
Like gode resultater kan oppnås ved å modifisere de kjemiske herdingsbetingelser som angitt i det følgende. Den kjemiske herdingsoppløsning kan fremstilles som følger (på vektprosentbasis): H20 : 70 til 90% Equally good results can be obtained by modifying the chemical curing conditions as indicated below. The chemical curing solution can be prepared as follows (on a weight percent basis): H20 : 70 to 90%
Stivelse : 2 til 10% Starch : 2 to 10%
KN03 : 4 til 12% KN03 : 4 to 12%
K2HP04 + K2HP04 +
K2S04 : 4 til 20% K2S04 : 4 to 20%
Stivelsen kan erstattes med et ekvivalent emulgerbart binde-middel . The starch can be replaced with an equivalent emulsifiable binder.
Varigheten av oppvarmingen kan være flere timer og tempera-turen kan være mellom 300 til 500°C. The duration of the heating can be several hours and the temperature can be between 300 to 500°C.
Resultatet er et dielektrisk material B' i samsvar med oppfinnelsen og de mekaniske egenskaper av dette er oppsummert i den etterfølgende Tabell I. Dielektrisk material A' er et tidligere kjent di-elektrisk material som er termisk herdet under forskjellige luftblåsetemperaturer og betingelser med relativ fuktighet. The result is a dielectric material B' in accordance with the invention and its mechanical properties are summarized in the following Table I. Dielectric material A' is a previously known dielectric material which is thermally hardened under different air blowing temperatures and conditions of relative humidity.
Det bemerkes at den kjemiske herdingsmetode i samsvar med oppfinnelsen er en industriell prosess med følgende fordeler: den anvender små mengder alkalimetallsalter og organiske It is noted that the chemical curing method according to the invention is an industrial process with the following advantages: it uses small amounts of alkali metal salts and organic
bindemidler da utgangsproduktet er en oppløsning, binders as the starting product is a solution,
den meget høye adhesjon av filmen etter tørking letter the very high adhesion of the film after drying facilitates
håndtering av de behandlede deler. handling of the treated parts.
Fremgangsmåten i samsvar med oppfinnelsen kan modifiseres ved inklusjon av en behandlingsfase før den nevnte kjemiske herding for å modifisere overflatesammensetningen av glasset av det dielektriske material slik at virkningen av den etter-følgende kjemiske herding økes. The method according to the invention can be modified by including a treatment phase before the aforementioned chemical hardening in order to modify the surface composition of the glass of the dielectric material so that the effect of the subsequent chemical hardening is increased.
Første eksempel: Glasset inneholder initialt kaliuminoer. First example: The glass initially contains potassium ions.
Det dielektriske material neddykkes i en oppløsning basert på natriumnitrat, tørkes og oppvarmes ved 450°C. For utjevning av spenningene som skyldes de resulterende ionebyttt-inger oppvarmes glasset på nytt til en temperatur over sin omvandlingstemperatur og kjemisk herding gjennomføres der-etter som beskrevet i det foregående. The dielectric material is immersed in a solution based on sodium nitrate, dried and heated at 450°C. To equalize the stresses due to the resulting ion exchanges, the glass is reheated to a temperature above its transformation temperature and chemical hardening is then carried out as described above.
Annet eksempel: Glasset inneholder initialt natriumioner. Det dielektriske material neddykkes i en oppløsning basert på litiumnitrat og natriumnitrat, hvoretter det tørkes og oppvarmes ved omtrent 350°C. For utjevning av spenningene som skyldes de resulterende ionbyttinger, oppvarmes glasset så til en temperatur over sin omvandlingstemperatur. Another example: The glass initially contains sodium ions. The dielectric material is immersed in a solution based on lithium nitrate and sodium nitrate, after which it is dried and heated at approximately 350°C. To equalize the stresses due to the resulting ion exchanges, the glass is then heated to a temperature above its transformation temperature.
Den etterfølgende kjemiske herding gjennomføres ved neddykking i en oppløsning av et natriumsalt for å tillate ionebytting mellom litium og natrium. Den kan i stedet gjennom-føres ved neddykking i en oppløsning av et natriumsalt og et kaliumsalt for å tillate ionebyttinger mellom litium og natrium på den ene side og natrium og kalium på den annen side. The subsequent chemical curing is carried out by immersion in a solution of a sodium salt to allow ion exchange between lithium and sodium. It can instead be carried out by immersion in a solution of a sodium salt and a potassium salt to allow ion exchanges between lithium and sodium on the one hand and sodium and potassium on the other.
lonebyttingen kan intensiveres ved å underkaste delene av det dielektriske material som behandles for et elektrisk felt under behandlingen for å medføre en "elektrovandringseffekt". the ion exchange can be intensified by subjecting the parts of the dielectric material being treated to an electric field during the treatment to bring about an "electromigration effect".
Claims (5)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR8120294A FR2515634A1 (en) | 1981-10-29 | 1981-10-29 | METHOD FOR MANUFACTURING A GLASS DIELECTRIC FOR ELECTRICAL AND DIELECTRIC ISOLATOR RESULTING THEREFROM |
Publications (3)
Publication Number | Publication Date |
---|---|
NO823548L NO823548L (en) | 1983-05-02 |
NO155618B true NO155618B (en) | 1987-01-19 |
NO155618C NO155618C (en) | 1987-04-29 |
Family
ID=9263517
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO823548A NO155618C (en) | 1981-10-29 | 1982-10-26 | ELECTRIC ISOLATOR WITH GLASS DIELECTRIC AND PROCEDURE FOR ITS MANUFACTURING. |
Country Status (11)
Country | Link |
---|---|
EP (1) | EP0078487B1 (en) |
JP (1) | JPS58100309A (en) |
AR (1) | AR240110A1 (en) |
AT (1) | ATE16993T1 (en) |
AU (1) | AU558928B2 (en) |
BR (1) | BR8206274A (en) |
CA (1) | CA1177652A (en) |
DE (1) | DE3268055D1 (en) |
FR (1) | FR2515634A1 (en) |
NO (1) | NO155618C (en) |
ZA (1) | ZA827891B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2563365B1 (en) * | 1984-04-20 | 1986-12-05 | Ceraver | GLASS DIELECTRIC FOR ELECTRICAL INSULATOR |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL6500068A (en) * | 1965-01-06 | 1966-07-07 | ||
DE1804839B1 (en) * | 1968-10-24 | 1969-12-04 | Jenaer Glaswerk Schott & Gen | Process for improving the mechanical strength of glass |
US4042405A (en) * | 1976-03-18 | 1977-08-16 | American Optical Corporation | High strength ophthalmic lens |
US4212919A (en) * | 1979-06-28 | 1980-07-15 | Corning Glass Works | Strengthened polychromatic glasses |
-
1981
- 1981-10-29 FR FR8120294A patent/FR2515634A1/en active Granted
-
1982
- 1982-10-26 EP EP82109873A patent/EP0078487B1/en not_active Expired
- 1982-10-26 DE DE8282109873T patent/DE3268055D1/en not_active Expired
- 1982-10-26 AT AT82109873T patent/ATE16993T1/en active
- 1982-10-26 NO NO823548A patent/NO155618C/en unknown
- 1982-10-27 BR BR8206274A patent/BR8206274A/en unknown
- 1982-10-27 AR AR291109A patent/AR240110A1/en active
- 1982-10-27 JP JP57188894A patent/JPS58100309A/en active Granted
- 1982-10-28 CA CA000414421A patent/CA1177652A/en not_active Expired
- 1982-10-28 ZA ZA827891A patent/ZA827891B/en unknown
- 1982-10-28 AU AU89871/82A patent/AU558928B2/en not_active Ceased
Also Published As
Publication number | Publication date |
---|---|
EP0078487B1 (en) | 1985-12-18 |
FR2515634A1 (en) | 1983-05-06 |
BR8206274A (en) | 1983-09-20 |
EP0078487A2 (en) | 1983-05-11 |
AU558928B2 (en) | 1987-02-12 |
CA1177652A (en) | 1984-11-13 |
JPS58100309A (en) | 1983-06-15 |
DE3268055D1 (en) | 1986-01-30 |
NO155618C (en) | 1987-04-29 |
FR2515634B1 (en) | 1984-10-26 |
NO823548L (en) | 1983-05-02 |
AR240110A1 (en) | 1990-01-31 |
EP0078487A3 (en) | 1983-07-20 |
JPS6313284B2 (en) | 1988-03-24 |
ZA827891B (en) | 1983-08-31 |
AU8987182A (en) | 1983-05-05 |
ATE16993T1 (en) | 1986-01-15 |
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