DE1197993B - Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal - Google Patents

Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal

Info

Publication number
DE1197993B
DE1197993B DEL22658A DEL0022658A DE1197993B DE 1197993 B DE1197993 B DE 1197993B DE L22658 A DEL22658 A DE L22658A DE L0022658 A DEL0022658 A DE L0022658A DE 1197993 B DE1197993 B DE 1197993B
Authority
DE
Germany
Prior art keywords
soldering
solder
gap
ceramic
metal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
DEL22658A
Other languages
German (de)
Inventor
Dr E H Guenther Dobke Dipl-Ing
Rudolf Heller
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Licentia Patent Verwaltungs GmbH
Original Assignee
Licentia Patent Verwaltungs GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Licentia Patent Verwaltungs GmbH filed Critical Licentia Patent Verwaltungs GmbH
Priority to DEL22658A priority Critical patent/DE1197993B/en
Publication of DE1197993B publication Critical patent/DE1197993B/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B37/00—Joining burned ceramic articles with other burned ceramic articles or other articles by heating
    • C04B37/02—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles
    • C04B37/023—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles characterised by the interlayer used
    • C04B37/026—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with metallic articles characterised by the interlayer used consisting of metals or metal salts
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J13/00—Discharge tubes with liquid-pool cathodes, e.g. metal-vapour rectifying tubes
    • H01J13/02—Details
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/02—Aspects relating to interlayers, e.g. used to join ceramic articles with other articles by heating
    • C04B2237/12—Metallic interlayers
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
    • C04B2237/32—Ceramic
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/30—Composition of layers of ceramic laminates or of ceramic or metallic articles to be joined by heating, e.g. Si substrates
    • C04B2237/40—Metallic
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/76—Forming laminates or joined articles comprising at least one member in the form other than a sheet or disc, e.g. two tubes or a tube and a sheet or disc
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/76—Forming laminates or joined articles comprising at least one member in the form other than a sheet or disc, e.g. two tubes or a tube and a sheet or disc
    • C04B2237/765—Forming laminates or joined articles comprising at least one member in the form other than a sheet or disc, e.g. two tubes or a tube and a sheet or disc at least one member being a tube
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/82—Two substrates not completely covering each other, e.g. two plates in a staggered position
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
    • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
    • C04B2237/84—Joining of a first substrate with a second substrate at least partially inside the first substrate, where the bonding area is at the inside of the first substrate, e.g. one tube inside another tube
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00—Discharge tubes and lamps
    • H01J2893/0072—Disassembly or repair of discharge tubes
    • H01J2893/0073—Discharge tubes with liquid poolcathodes; constructional details

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Ceramic Products (AREA)

Description

Verfahren zur Herstellung von vakuumdichten Verbindungen zwischen Keramikrohren und Hülsen oder Deckeln aus Metall Für Quecksilberdampf-Stromrichtergefäße werden Stromeinführungen verlangt, die den folgenden Bedingungen entsprechen sollen: 1. große mechanische Festigkeit, 2. Temperaturfestigkeit bis 600° C, 3. Verwendung einfacher und billiger Ausgangsstoffe, 4. Eignung für Massenanfertigung.Process for the production of vacuum-tight connections between Ceramic tubes and sleeves or lids made of metal For mercury vapor converter vessels current entries are required which should meet the following conditions: 1. Great mechanical strength, 2. Temperature resistance up to 600 ° C, 3. Use simple and cheaper raw materials, 4. suitability for mass production.

Diese Bedingungen werden erfüllt durch Stromeinführungen aus keramischen Rohren, die mit metallischen ringförmigen Körpern mittels eines Hartlotes, beispielsweise Silber, verbunden werden. Zuverlässige Verbindungen dieser Art können durch gleichzeitige Erhitzung des Keramikteils und der mit ihm zu verbindenden Metallteile hergestellt werden, da in diesem Fall weniger die Gefahr besteht, daß infolge ungleichmäßiger Erwärmung im Keramikteil gefährliche Spannungen entstehen. Die Herstellung der vakuumdichten Verbindung wird zweckmäßig in einem elektrisch beheizten Ofen vorgenommen. Für die Aufnahme des Lötmittels, das in Form von Blechstreifen eingeführt wird, ist zwischen dem Metall- und dem Keramikteil ein Spalt vorgesehen. Während der Erwärmung auf Löttemperatur wird ein Teil des Spaltes von dem zerfließenden Lot lückenlos ausgefüllt. Diese Methode, bei der das Lötmittel vor der Lötung in fester Form in den Verbindungsspalt gebracht wird, eignet sich aber nur für Stromeinführungen mit kleineren Durchmessern, sie kann z. B. schon bei einer Stromeinführung mit einem Durchmesser von 100 mm, nicht mehr zuverlässig angewendet werden.These conditions are met by current inlets made of ceramic Tubes that are connected to metallic ring-shaped bodies by means of a hard solder, for example Silver, to be connected. Reliable connections of this type can be achieved through simultaneous Heating of the ceramic part and the metal parts to be connected to it made be, since in this case there is less risk of being uneven as a result Heating in the ceramic part creates dangerous voltages. The manufacture of the vacuum-tight Connection is expediently made in an electrically heated oven. For the Reception of the solder, which is introduced in the form of sheet metal strips, is between the metal and the ceramic part provided a gap. While heating up At the soldering temperature, part of the gap is completely filled by the flowing solder. This method in which the solder before soldering in solid form into the joint gap is brought, but is only suitable for current entries with smaller diameters, she can z. B. already with a power inlet with a diameter of 100 mm, can no longer be used reliably.

Die Erfindung bezieht sich auf eine Anordnung zur Herstellung von vakuumdichten Verbindungen zwischen Keramikrohren und Hülsen oder Deckeln aus Metall durch Löten, bei der die Metallhülse und der Keramikkörper sich nicht berühren, innerhalb eines sauerstofffreien Ofens, z. B. eines Vakuumofens, und besteht darin, daß im Inneren des Keramikrohres für jede Lötnaht je ein von einem Schmelz-Ofen umgebenes Lötvorratsgefäß vorgesehen ist, das am unteren Ende über ein Gießrohr mit dem entsprechenden Lötspalt lösbar verbunden ist, und die Abflußöffnungen der Lötvorratsgefäße derart angeordnet sind, daß die Niveauoberflächen des flüssigen Lotes höher liegen als die Lötspalte, und daß zur Verhinderung des Auslaufens des Lotes aus dem Lötspalt ein Graphitring derart ausgebildet ist, daß er am Ende der Lötspalte fest an dem Keramikrohr anliegt und in einer Aussparung das zu verbindende Ende der Metallhülse trägt.The invention relates to an arrangement for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal by soldering, in which the metal sleeve and the ceramic body do not touch, inside an oxygen-free oven, e.g. B. a vacuum furnace, and consists of that inside the ceramic tube for each soldered seam one from a melting furnace surrounded solder supply vessel is provided, which at the lower end via a pouring pipe is releasably connected to the corresponding soldering gap, and the drainage openings of the Solder supply vessels are arranged such that the level surfaces of the liquid Solder higher than the soldering gap, and that to prevent the leakage of the A graphite ring is formed such that it is at the end of the solder from the soldering gap Soldering gap rests firmly on the ceramic tube and the one to be connected in a recess End of the metal sleeve carries.

Die Figur zeigt in zum Teil schematischer Darstellung ein Ausführungsbeispiel der erfindungsgemäßen Anordnung.The figure shows an exemplary embodiment in a partially schematic representation the arrangement according to the invention.

Das Keramikrohr 1 soll mit dem Deckel 2 und der Hülse 3 durch das Lot verbunden werden. Da bei Stromeinführungen mit größerem Durchmesser, z. B. 100 mm, die Konzentrierung der Teile während der Lötung nicht mehr gesichert ist, wird sie durch mechanische Mittel herbeigeführt. Zu diesem Zweck ist ein zweiteiliger Graphitring 4 vorgesehen, der bei Löttemperatur zugleich das Keramikrohr und das Ende des Metallzylinders eng umschließt. Der am Keramikrohr anliegende Rand des Graphitringes bildet gleichzeitig den äußeren Abschluß des Verbindungsspaltes 5. Mittels eines weiteren Graphitringes 6 wird der halbierte Graphitring 4 zusammengehalten und somit der Metallzylinder zu dem Keramikrohr 1 konzentriert bzw. die koaxiale Lage der Teile erzwungen. Der genaue Abstand zwischen den beiden Graphitringen 4 wird beispielsweise durch vier auf den Umfang verteilte Exzenterzapfen 7 abgestimmt.The ceramic tube 1 is to be connected to the cover 2 and the sleeve 3 by the solder. Since with current inlets with a larger diameter, z. B. 100 mm, the concentration of the parts is no longer ensured during soldering, it is brought about by mechanical means. For this purpose, a two-part graphite ring 4 is provided, which at the same time tightly encloses the ceramic tube and the end of the metal cylinder at the soldering temperature. The edge of the graphite ring resting on the ceramic tube also forms the outer closure of the connecting gap 5. The halved graphite ring 4 is held together by means of a further graphite ring 6 , thus concentrating the metal cylinder to the ceramic tube 1 or enforcing the coaxial position of the parts. The exact distance between the two graphite rings 4 is matched, for example, by four eccentric pins 7 distributed around the circumference.

Innerhalb des Keramikrohres 1 werden zwei Lotvorratsgefäße 8 und 9 übereinander eingesetzt und von einem Ofen 10 umgeben. Die Lotvorratsgefäße sind über je ein Kupplungsrohr 11 und 12 und über je eine in den Einsatzringen 13 und 14 vorgesehene Nut 15 mit dem Raum des Verbindungsspaltes verbunden. Wird durch den Ofen 10 das Lot in den Vorratsgefäßen 8 und 9 geschmolzen, dann fließt es über das Kupplungsrohr und die Nut in den Verbindungsspalt und füllt diesen vollkommen aus.Within the ceramic tube 1, two solder storage vessels 8 and 9 are inserted one above the other and surrounded by an oven 10. The solder reservoirs are each connected to the space of the connecting gap via a coupling tube 11 and 12 and via a groove 15 provided in each of the insert rings 13 and 14. If the solder in the storage vessels 8 and 9 is melted by the furnace 10 , it then flows through the coupling tube and the groove into the connecting gap and fills it completely.

Der das Keramikrohr umschließende Teil der Metallzylinder besteht oft aus einheitlichem Material, z. B. Eisen, unter Umständen wird aber die Verwendung von Schrumpfringen 16 und 17 mit besonderen thermischen Eigenschaften vorgezogen. Vorteilhafterweise wird das ganze Verfahren in einem elektrisch beheizten sauerstofffreien Ofen, z. B. einem Vakuumofen, vorgenommen. Es werden so die zu verbindenden Teile gleichmäßig erwärmt, und es wird verhindert, daß das Lot an weniger erwärmten Teilen zu früh erstarrt und den Spalt nicht mehr voll ausfüllen kann. Gleichzeitig wird eine Oxydierung der Metall- und Graphitteile vermieden.The part of the metal cylinder surrounding the ceramic tube is made often made of a single material, e.g. B. iron, but may be the use preferred by shrink rings 16 and 17 with special thermal properties. Advantageously the whole process is carried out in an electrically heated oxygen-free oven, e.g. B. a vacuum furnace. In this way, the parts to be connected are uniform heated, and it prevents the solder on less heated parts too early solidifies and can no longer completely fill the gap. At the same time there is an oxidation the metal and graphite parts avoided.

Claims (3)

Patentansprüche: 1. Anordnung zur Herstellung von vakuumdichten Verbindungen zwischen Keramikrohren und Hülsen oder Deckeln aus Metall durch Löten, bei der die Metallhülse und der Keramikkörper sich nicht berühren, innerhalb eines sauerstofffreien Ofens, z. B. eines Vakuumofens, d a -durch gekennzeichnet, daß im Inneren des Keramikrohres für jede Lötnaht je ein von einem Schmelzofen umgebenes Lötvorratsgefäß vorgesehen ist, das am unteren Ende über ein Gießrohr mit dem entsprechenden Lötspalt lösbar verbunden ist, und die Abflußöffnungen der Lötvorratsgefäße derart angeordnet sind, daß die Niveauoberflächen des flüssigen Lotes höher liegen als die Lötspalte, und daß zur Verhinderung des Auslaufens des Lotes aus dem Lötspalt ein Graphitring derart ausgebildet ist, daß er am Ende der Lötspalte fest an dem Keramikrohr anliegt und in einer Aussparung das zu verbindende Ende der Metallhülse trägt. Claims: 1. Arrangement for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal by soldering, in which the Metal sleeve and the ceramic body do not touch, within an oxygen-free Furnace, e.g. B. a vacuum furnace, d a -characterized in that inside the ceramic tube for each soldered seam a soldering reservoir surrounded by a melting furnace is provided is, which can be released at the lower end via a pouring pipe with the corresponding soldering gap is connected, and the drainage openings of the soldering reservoirs are arranged in such a way that the level surfaces of the liquid solder are higher than the soldering gap, and that to prevent the solder from leaking out of the soldering gap a graphite ring in such a way is designed that it rests firmly against the ceramic tube at the end of the soldering gap and the end of the metal sleeve to be connected carries in a recess. 2. Anordnung nach Anspruch 1, dadurch gekennzeichnet, daß oberhalb bzw. unterhalb des Keramikrohres ein dicht an der Stirnfläche des Keramikrohres anliegender Einsatzring angeordnet ist, der den Lötspalt an der Innenseite begrenzt, und der mit einer Nut versehen ist, durch die das flüssige Lot aus dem Lotvorratsgefäß in den Lötspalt fließt. 2. Arrangement according to claim 1, characterized in that above or below the ceramic tube an insert ring fitting tightly to the end face of the ceramic tube is arranged that delimits the soldering gap on the inside and that is provided with a groove through which the liquid solder flows from the solder reservoir into the soldering gap. 3. Anordnung nach Anspruch 1, dadurch gekennzeichnet, daß bei mehreren Lötverbindungen die Graphitringe durch einen gemeinsamen Graphitring verbunden sind und an ihm ein Exzenterzapfen vorgesehen ist, durch den der erste Graphitring justierbar ist. In Betracht gezogene Druckschriften: Deutsche Patentschriften Nr. 681728, 739 972, 762 675; schweizerische Patentschrift Nr. 265 322; französische Patentschrift Nr. 843 524.3. Arrangement according to claim 1, characterized in that with several soldered connections the graphite rings are connected by a common graphite ring and one on it Eccentric pin is provided through which the first graphite ring is adjustable. In Considered publications: German patent specifications No. 681728, 739 972, 762 675; Swiss Patent No. 265 322; French patent specification no. 843 524.
DEL22658A 1955-08-08 1955-08-08 Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal Pending DE1197993B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DEL22658A DE1197993B (en) 1955-08-08 1955-08-08 Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DEL22658A DE1197993B (en) 1955-08-08 1955-08-08 Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal

Publications (1)

Publication Number Publication Date
DE1197993B true DE1197993B (en) 1965-08-05

Family

ID=7262462

Family Applications (1)

Application Number Title Priority Date Filing Date
DEL22658A Pending DE1197993B (en) 1955-08-08 1955-08-08 Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal

Country Status (1)

Country Link
DE (1) DE1197993B (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR843524A (en) * 1937-09-21 1939-07-05 Pintsch Julius Kg Annular weld between a ceramic part and a metal
DE681728C (en) * 1936-07-09 1939-09-29 Rudolf Scharfnagel Dr Method for joining ceramic bodies to metal
DE739972C (en) * 1936-05-13 1943-10-08 Aeg Process for the production of vacuum-tight connections between bodies made of metal and non-pre-metallized ceramic surfaces
CH265322A (en) * 1942-10-05 1949-11-30 Secheron Atel Metal and ceramic parts connected to one another by a high vacuum-tight ring fusion.
DE762675C (en) * 1937-05-29 1954-10-18 Lorenz C Ag Method for holding two-part power feedthroughs in ceramic insulating bodies for electrical discharge vessels

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE739972C (en) * 1936-05-13 1943-10-08 Aeg Process for the production of vacuum-tight connections between bodies made of metal and non-pre-metallized ceramic surfaces
DE681728C (en) * 1936-07-09 1939-09-29 Rudolf Scharfnagel Dr Method for joining ceramic bodies to metal
DE762675C (en) * 1937-05-29 1954-10-18 Lorenz C Ag Method for holding two-part power feedthroughs in ceramic insulating bodies for electrical discharge vessels
FR843524A (en) * 1937-09-21 1939-07-05 Pintsch Julius Kg Annular weld between a ceramic part and a metal
CH265322A (en) * 1942-10-05 1949-11-30 Secheron Atel Metal and ceramic parts connected to one another by a high vacuum-tight ring fusion.

Similar Documents

Publication Publication Date Title
DE2744435C2 (en) Induction heated ladle
DE3118750C1 (en) Melting crucible for small quantities
WO1986000973A1 (en) Tubular quartz-glass element with a flange
DE1197993B (en) Process for the production of vacuum-tight connections between ceramic tubes and sleeves or covers made of metal
CH344489A (en) Process for the production of vacuum-tight connections between ceramic tubes and sleeves made of metal
DE1121347B (en) Electromagnetic flow meter, especially for liquids with high temperature and under high pressure
EP0077513B1 (en) Method of preventing the consumption of a current-conducting electrode for metallurgical furnaces, and electrode
DE860979C (en) Metallic implementation through a ceramic vacuum vessel
DE705000C (en) Tapping for high frequency induction furnaces
DE815741C (en) Device for brazing pipe connections
DE1038973B (en) Process for producing vacuum-tight connections between ceramic tubes and sleeves or lids made of metal
CH359396A (en) Process for producing vacuum-tight connections between ceramic tubes and metal sleeves
DE704846C (en) Electrical discharge vessel with one or more ceramic components at least partially forming the vacuum-tight vessel wall and a method for its manufacture
DE546686C (en) Injection molding machine with pressure chamber for processing magnesium and its alloys
DE1130245B (en) Hand tool for point-like electrolytic treatment of metallic objects
DE766053C (en) Exchangeable anode lead-through for metal vapor rectifier with metal vessel wall
DE700423C (en) Tiltable vacuum furnace for light metal melts
DE2251147A1 (en) CONICAL PIPE SOCKET CARRYING A FLANGE RING
DE673474C (en) Metal vapor converters, especially grid-controlled mercury vapor rectifiers
DE763708C (en) Metal vapor discharge vessel
DE595696C (en) Spark plug
DE924818C (en) Manufacture of high-vacuum-tight solder connections between parts made of ceramic and metallic material by melting the solder under the action of mechanical pressure
DE1458804C (en) Device for degassing melts under vacuum
AT200410B (en) Automatic hand-held device for electrolytic treatment for metallographic testing of metal objects
DE741548C (en) Device for casting machine parts