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The controcl of the atmosphere in the gas phase of a vacuum melting furnance by chromography
Classified abstracts
185-l 94
ess efficient. Analysis of such readings gives a good idea of the effect of external conditions on the efficiency of vacuum pumps. S G Appel’, Soviet Patent, class G 07 c, 3110, No. 382117, claimed 5th July 1971, publd 1st Aug 1973 (in Russian). 21
manner so that the pressure differentials acting around the groove keep them firmly in place and exclude corrosive products, their finite elasticity ensuring the absence of gaps. A G Evtyugin and S Ya Sheinin, Soviet Patent, class F 16 j, 13102, No. 382867, claimed 3rd Aug 1971, publd 12th Sept 1973 (in Russian).
185. A getter-ion pump. (USSR)
An invention designed to increase the stability of the evaporation of the getter material in a getter-ion pump by ensuring a constant area of the evaporation surface is described. The rod of getter material is placed coaxially with the anode and is sorrounded by thermallyinsulating screens, preventing electrons from falling on to the sides of the rod. The anode lies along the axis of the cylindrical body of the pump in the form of a thin rod serving to create the ionization field, and the electrons from the cathode move in elliptical spirals around the anode, ionizing the residual gas. The geometry of the emitting surface of the getter remains constant during the evaporation, and stable working conditions are ensured; the rate of evaporation.is controlled by varying the potential on the getter rod. A S Naxarov et al, Soviet Patent. class H 01 i. 41/00, No. 382171. claimed 1st Feb 1971, publd 13th Aug 1973 (in Russian):
191. An inspection window for a vacuum chamber. (USSR) An improved inspection window for a vacuum chamber is described; its distinctive feature lies in the fact that it is supplied with a condenser, made in the form of a confusor, and mounted by means of a ball-bearing support in the vacuum-tight body. On the outside the inspection window may be directly connected to optical apparatus for recording purposes. A cooling system is also provided in the neighbouring parts of the body. The operation of the vacuum chamber and its attached inspection window depends on the propagation of a molecular beam of evaporated material in the direction of the window, its points of deposition being carefully controlled by virtue of artificially-regulated temperature gradients. A Yu Abel, and Yu A Akimov, Soviet Patent, class C 23 c, 13108, No. 382771, claimed 1st Feb 1971, publd 14th Aug 1973 (in Russian).
23. PLUMBING
23 186. Windowless
seal for photomultiplier
tubes. (USA)
Direct sealing of a photomultiplier to a vacuum system eliminates signal loss in an extra window. (USA) P Davis et al, Rev Scient Instrum,
45 (7), 1974, 961-962. 23
187. A demountable
circular inspection window. (USSR)
A new form of circular demountable inspection window for vacuum installations is described; its construction is aimed at securing greater strength and heat resistance of the transparent part than heretofore. This is achieved by making the contact surfaces of the rim and the transparent piece in the middle with conical edges and filling the space between them with a suitable interlayer. The angle of the cone is normally 15-25”. The actual transparent part may be made of glass and the interlayer of some kind of polymer. I P Derbenev and A M Maxnitsa, Soviet Patent, class E 06 B, 7130, No. 387111, claimed 9th Dee 1966, publd 19th Ott 1973 (in Russian). 23 188. Sealing system for a vacuum &amber.
(USSR) In existing sealing systems for vacuum chambers, initial hermetization is achieved by means of a complex array of clamps, controlled, for example, by hydraulic drives. In the invention here described the construction of this array is simplified by incorporating a hollow elastic element, the inside of which communicates with a source of excess pressure. This element fultils the function of clamp during the preliminary sealing of, for example, the lid to a vacuum vessel; it may operate as a pulse device. A I Martinson, Soviet Patent, class F 16 j, 1l/06, No. 385111, claimed 5th Jan 1970, publd 17th Ott 1973 (in Russian). 189. A lever device for transmitting
23 complex motion in vacua. (USSR) complex motion in yacuo is des-
A lever system for transmitting cribed; it differs from existing versions in having a wedge mechanism incorporating a prism and pull-rod fixed in the body of the evacuated vessel, with the ability to execute to-and-fro motion. The guiding rod moves in three dimensions and enables the lever to execute forward (translational) motion and also rotation, so by virtue of a series of simple couplings producing almost any desired motion of the guided parts. A coarse adjustment giving the initial position of the movable parts is made when the system is first assembled. 0 D Smiyan, Soviet Patent, class F 16 h, 21/08, No. 381827, claimed
27. LEAK
DETECTORS
AND LEAK DETECTION
27 192. A leak detector. (USSR) The leak detector here described differs from existing models in that the system for estimating the leak is made in the form of a U-shaped vessel filled with an aqueous solution of the indicator (1% phenolphthalein solution); one branch is made with a larger diameter in its central section, with the aim of increasing sensitivity. The accuracy of the device depends to a great extent on the choice of relative dimensions in the various parts of the U tube, and to this end a selection of large-diameter sections is provided. The ratio of the diameters of the wide and narrow parts in general lies between 1.5 and 5; the height of the large-diameter section is normally 30-40 mm. The indicator occupies not more than 0.6 of the height of this section. Gas leaks passing, for example, from an imperfect metal vessel into this device change the colour of the indicator and this acts as a measure of the leak. A I Khristin, Soviet Patent, class G 01 m, 3120, No. 351112, claimed 26th May 1970, publd 11th Ott 1972 (in Russian). 28. HEATING
EQUIPMENT
AND THERMOMETERS 28
193. The control of the atmosphere
in tbe gas phase of a vacuum
melting furnace by chromatography.
(France) The knowledge of the atmosphere prevailing in a melting chamber of a vacuum furnace allows us to rationalize the control of that furnace. The chromatography in a gaseous phase rapidly produces both a qualitative and quantitative analysis of that atmosphere. The use of argon as a carrier-gas allows an easy dosage of H2 (Hydrogen) CO (carbon monoxide) COZ (carbon dioxide) N, (nitrogen) O2 (oxygen) and H,O (water). This means all the main important gases which are produced in the vacuum furnace. After describing the changes brought to the original material the article continues with the operation of a nickel-base alloy. The development of the furnace atmosphere’s composition has shown that the initial operation’s order does not correspond to the optimum conditions on a technical level (percentage of the gas in the cast product) as well as on an economic one. (Time of the operation). The output of this initial programme can be heightened without any damage to the molten alloy’s quality. (Switzerland). H Feichtinger and J Durr, Vide, 29 (169). 1974, 283-288
(in French).
2nd Dee 1968, publd 24th Ott 1973 (in Russian). 23 190. Sealing of vacuum chambers. (USSR)
A method of protecting the seals of vacuum chambers from corrosive products arising during the operation of the latter is described. Protection is effected by retaining the rubber seal in a deep groove in the vacuum flange and preventing contact with corrosive gases by means of a system of overlapping, chemically-stable plates (for example, plates made from Teflon). The gap between the seal and the plates is flushed with a weak flow of air or inert gas by way of an additional protective screen. The plates are arranged in a fan-like 86
III.
Vacuum
30. EVAPORATION
applications AND SPUTTERING
30 194. The growth and structure of epitaxial rhodium films. (GB) Single-crystal rhodium films have been epitaxially grown by vacuum evaporation on the cubic, octahedral and dodecahedral planes of
185-l 94
ess efficient. Analysis of such readings gives a good idea of the effect of external conditions on the efficiency of vacuum pumps. S G Appel’, Soviet Patent, class G 07 c, 3110, No. 382117, claimed 5th July 1971, publd 1st Aug 1973 (in Russian). 21
manner so that the pressure differentials acting around the groove keep them firmly in place and exclude corrosive products, their finite elasticity ensuring the absence of gaps. A G Evtyugin and S Ya Sheinin, Soviet Patent, class F 16 j, 13102, No. 382867, claimed 3rd Aug 1971, publd 12th Sept 1973 (in Russian).
185. A getter-ion pump. (USSR)
An invention designed to increase the stability of the evaporation of the getter material in a getter-ion pump by ensuring a constant area of the evaporation surface is described. The rod of getter material is placed coaxially with the anode and is sorrounded by thermallyinsulating screens, preventing electrons from falling on to the sides of the rod. The anode lies along the axis of the cylindrical body of the pump in the form of a thin rod serving to create the ionization field, and the electrons from the cathode move in elliptical spirals around the anode, ionizing the residual gas. The geometry of the emitting surface of the getter remains constant during the evaporation, and stable working conditions are ensured; the rate of evaporation.is controlled by varying the potential on the getter rod. A S Naxarov et al, Soviet Patent. class H 01 i. 41/00, No. 382171. claimed 1st Feb 1971, publd 13th Aug 1973 (in Russian):
191. An inspection window for a vacuum chamber. (USSR) An improved inspection window for a vacuum chamber is described; its distinctive feature lies in the fact that it is supplied with a condenser, made in the form of a confusor, and mounted by means of a ball-bearing support in the vacuum-tight body. On the outside the inspection window may be directly connected to optical apparatus for recording purposes. A cooling system is also provided in the neighbouring parts of the body. The operation of the vacuum chamber and its attached inspection window depends on the propagation of a molecular beam of evaporated material in the direction of the window, its points of deposition being carefully controlled by virtue of artificially-regulated temperature gradients. A Yu Abel, and Yu A Akimov, Soviet Patent, class C 23 c, 13108, No. 382771, claimed 1st Feb 1971, publd 14th Aug 1973 (in Russian).
23. PLUMBING
23 186. Windowless
seal for photomultiplier
tubes. (USA)
Direct sealing of a photomultiplier to a vacuum system eliminates signal loss in an extra window. (USA) P Davis et al, Rev Scient Instrum,
45 (7), 1974, 961-962. 23
187. A demountable
circular inspection window. (USSR)
A new form of circular demountable inspection window for vacuum installations is described; its construction is aimed at securing greater strength and heat resistance of the transparent part than heretofore. This is achieved by making the contact surfaces of the rim and the transparent piece in the middle with conical edges and filling the space between them with a suitable interlayer. The angle of the cone is normally 15-25”. The actual transparent part may be made of glass and the interlayer of some kind of polymer. I P Derbenev and A M Maxnitsa, Soviet Patent, class E 06 B, 7130, No. 387111, claimed 9th Dee 1966, publd 19th Ott 1973 (in Russian). 23 188. Sealing system for a vacuum &amber.
(USSR) In existing sealing systems for vacuum chambers, initial hermetization is achieved by means of a complex array of clamps, controlled, for example, by hydraulic drives. In the invention here described the construction of this array is simplified by incorporating a hollow elastic element, the inside of which communicates with a source of excess pressure. This element fultils the function of clamp during the preliminary sealing of, for example, the lid to a vacuum vessel; it may operate as a pulse device. A I Martinson, Soviet Patent, class F 16 j, 1l/06, No. 385111, claimed 5th Jan 1970, publd 17th Ott 1973 (in Russian). 189. A lever device for transmitting
23 complex motion in vacua. (USSR) complex motion in yacuo is des-
A lever system for transmitting cribed; it differs from existing versions in having a wedge mechanism incorporating a prism and pull-rod fixed in the body of the evacuated vessel, with the ability to execute to-and-fro motion. The guiding rod moves in three dimensions and enables the lever to execute forward (translational) motion and also rotation, so by virtue of a series of simple couplings producing almost any desired motion of the guided parts. A coarse adjustment giving the initial position of the movable parts is made when the system is first assembled. 0 D Smiyan, Soviet Patent, class F 16 h, 21/08, No. 381827, claimed
27. LEAK
DETECTORS
AND LEAK DETECTION
27 192. A leak detector. (USSR) The leak detector here described differs from existing models in that the system for estimating the leak is made in the form of a U-shaped vessel filled with an aqueous solution of the indicator (1% phenolphthalein solution); one branch is made with a larger diameter in its central section, with the aim of increasing sensitivity. The accuracy of the device depends to a great extent on the choice of relative dimensions in the various parts of the U tube, and to this end a selection of large-diameter sections is provided. The ratio of the diameters of the wide and narrow parts in general lies between 1.5 and 5; the height of the large-diameter section is normally 30-40 mm. The indicator occupies not more than 0.6 of the height of this section. Gas leaks passing, for example, from an imperfect metal vessel into this device change the colour of the indicator and this acts as a measure of the leak. A I Khristin, Soviet Patent, class G 01 m, 3120, No. 351112, claimed 26th May 1970, publd 11th Ott 1972 (in Russian). 28. HEATING
EQUIPMENT
AND THERMOMETERS 28
193. The control of the atmosphere
in tbe gas phase of a vacuum
melting furnace by chromatography.
(France) The knowledge of the atmosphere prevailing in a melting chamber of a vacuum furnace allows us to rationalize the control of that furnace. The chromatography in a gaseous phase rapidly produces both a qualitative and quantitative analysis of that atmosphere. The use of argon as a carrier-gas allows an easy dosage of H2 (Hydrogen) CO (carbon monoxide) COZ (carbon dioxide) N, (nitrogen) O2 (oxygen) and H,O (water). This means all the main important gases which are produced in the vacuum furnace. After describing the changes brought to the original material the article continues with the operation of a nickel-base alloy. The development of the furnace atmosphere’s composition has shown that the initial operation’s order does not correspond to the optimum conditions on a technical level (percentage of the gas in the cast product) as well as on an economic one. (Time of the operation). The output of this initial programme can be heightened without any damage to the molten alloy’s quality. (Switzerland). H Feichtinger and J Durr, Vide, 29 (169). 1974, 283-288
(in French).
2nd Dee 1968, publd 24th Ott 1973 (in Russian). 23 190. Sealing of vacuum chambers. (USSR)
A method of protecting the seals of vacuum chambers from corrosive products arising during the operation of the latter is described. Protection is effected by retaining the rubber seal in a deep groove in the vacuum flange and preventing contact with corrosive gases by means of a system of overlapping, chemically-stable plates (for example, plates made from Teflon). The gap between the seal and the plates is flushed with a weak flow of air or inert gas by way of an additional protective screen. The plates are arranged in a fan-like 86
III.
Vacuum
30. EVAPORATION
applications AND SPUTTERING
30 194. The growth and structure of epitaxial rhodium films. (GB) Single-crystal rhodium films have been epitaxially grown by vacuum evaporation on the cubic, octahedral and dodecahedral planes of