US1601326A

US1601326A - Deoxidizing apparatus

Info

Publication number: US1601326A
Application number: US665408A
Authority: US
Inventors: Clarence J Rodman; Leland H Hill
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1923-09-28
Filing date: 1923-09-28
Publication date: 1926-09-28
Anticipated expiration: 1943-09-28

Description

2 Sheets-Sheet 1 DEOXIDIZING APPARATUS Filed Sept. 28, 1923 C. J. RODMAN ET AL Sept. 28 1926.

I I!!! V ATTORNEY s R O T N E v m C/arenc e J Raom an.

L e/ana H. Hi/l.

WITNESSES:

C. J. RODMAN ET AL DEOXIDIZING APPARATUS Sept. 28 1926.

Filed Sept. 28, 1923 2 Sheets-Sheet 2 lNVENTOR Clarence J. Rod/nan. L e/and H. Hill. BY

ATTORNEY ing oil.

Patented Sept. 28, 1926.

UNITED STATES PATENT OFFICE.

ULARENCE j. RODMAN AND LELAND H. HILL, 0] WILKINSBURG, PENNSYLVANIA, AS- SIGNORS T0 WESTINGHOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORA- TION OF PENNSYLVANIA.

DEOXIDIZING APPARATUS.

Application filed September 28, 1923. Serial No. 665,408.

Our invention relates to deoxidizing apparatus and it has particular relation to respirators for deoxidizing the air within the casings of electrical apparatus, such, for example, as transformers, circuit breakers, or the like.

Our invention has, for one of its objects, to provide a simple and reliable apparatus for effectually removing oxygen from the an initially in or entering the casings of electrical apparatus.

A second object of our invention Is to provide a deoxidizing apparatus of the character described above, in which the length of the path of travel of air or gases therethrough and the drop in pressure caused thereby are reduced to a minimum.

In the operation of transformers, circuitbreakers and similar electrical apparatus employing oil or other hydrocarbon compounds for insulating purposes, it has been found that the vapors and the gases arising from the volatilization or the breaking down of the oils constitutes an explosive mixture that is a source of danger to property and to operating personnel. Such gases may collect in the space above the oil and may be exploded upon the occurrence of an arc arising by reason of a short circuit or other condition.

It has been demonstrated that the danger of explosions of the character set forth above may be substantially entirely eliminated if substantially no oxygen is present in the air or gas occupying the space above the insulat- In accordance with the present invention, this condition is obtained by employing a respirator or deoxidizin apparatus that is provided with a suita le material for removing oxygen from the air originally within the tank or from such an as may enter the tank by reason of changes in volume of the oil caused by variations in temperature.

In the accompanying drawings,

Figure 1 is a view, partially in section and partially in elevation, of a transformer with our invention applied thereto;

Fig. 2 is a view in transverse section, taken along the line 22 of Fig. 1;

Fig. 3 is a view, similar to Fig. 1, of a modified form of our invention; and

Figs. 4, 5 and 6 are views in transverse section of modified forms of the deoxidizing apparatus.

' Referring to Figs. 1 and 2, a transformer 1 is rovided with a casing 2 having a cover mem er 3 through which the terminals of the transformer extend to suitable condenser bushings 4 and 5. The casing 2 is filled with oil, in icated at 6, to any desired level above the transformer proper.

A respirator or deoxidizing apparatus 8 that is attached to the side wall of the casing 2 and that is in communication with the air space 9 above the oil comprises an outer casing member 10 having a removable cover 11 and a removable bottom member 12 and a container 13 for deoxidizing and dehydrating material that is provided with side walls of perforated material, which may be, for example, sheet metal, expanded metal, woven material, or other similar or suitable materials. The container 13 is provided with a suitable deoxi'dizing material indicated at 14 that is preferably that constituting the subject-matter of the copending application of C. J. Rodman and A. H. Maude, Serial No. 652,668, filed July 20, 1923, and assigned to the Westinghouse Electric & Manufacturing Company. The container 13 is so disposed within the casing 10 that its front and ack walls are spaced therefrom, except that the upper edges of the walls are secured to the casing. The edges of the wall portions of the container are connected to the side walls of the casing 10. The container 13 is so completely filled with deoxidizing material 14 that it constitutes a partition for dividing the space within the container 10 into two

compartments

16 and 17, communication between which may be had only through the deoxidizing material 14. The compartment 16 communicates with the interior of the transformer casing by means of a screened opening 18 in the latter. The com artment 17 is connected to the atmosphere t rough a relief valve 19 for regulating the breathing of the transformer through the respirator.

The relief valve 19 is substantially that constituting the subject-matter of the copending application of L. H. Hill, Serial No. 608,791, filed Dec. 23, 1922, and assigned to the Westinghouse Electric & Manufacturing Company. The valve 19 is similar in prin ciple to that of the well-known U-tube, except that the pressures at which it may operate in the respective directions differ in accordance with the heads of liquid to be overcome.

The relief valve 19 comprises a container or receptacle 21 for a suitable liquid, such, for example, as mercury, to constitute a liquid seal. The valve is also provided with an air inlet tube 22 and an .air outlet tube 23, the former of which is connected to the space above the liquid and the latter of which extends below the surface of the liquid. A spillway tube 24 returns any liquid carried up the tube 23.

This arrangement provides that the pressure necessary to permit air to enter the outlet tube and pass through the receptacle 21 and tube 22 is that equal to the head of liquid in tube 23. The pressure necessary for air or gas to flow in the opposite direction is dependent upon the relative horizontal crosssectional areas of the

tubes

23 and 24 and the receptacle 21, since the level of the liquid in 'the receptacle must be depressed by being forced up the

tubes

23 and 24 until the open end of pipe 23 is uncovered. By way of example, the degree of vacuum required to draw air through the respirator 8 and valve 19 may be one-fourth of one pound, while a pressure of five pounds above atmospheric pressure may be necessary to expel gas or air from the transformer.

It may be desirable to obtain a sample of the gas within the transformer in order to determine its content of oxygen. Accordingly, I provide a pipe 26 extending from the opening 18 through the compartment 16 and into the casing 27 of the relief valve; the end of the pipe being provided with a suitable. stop-cock 28.

It may be assumed that the transformer is being placed in operation. The heat losses in the transformer windings and the core member increase the temperature of the surrounding oil and the latter expands to correspondingly increase the pressure of the air or gases within the space 9. When the pressure exceeds the predetermined value for which the valve 19 is arranged, air is expelled through the respirator and valve 19 into the atmosphere.

In case the temperature of the transformer falls, such, for example, as by reason of varying load conditions, the volume of the oil decreases and the pressure of the air within the s ace 9 falls below atmospheric pressure. en the difference in pressure reaches a predetermined value, the valve l9 admits air into the compartment 17 and through the deoxidizing material 14, the

compartment 16 and o ning 18 into the space 9. Theair entering the transformer is effectually deoxidized and dehydrated,

. substantially pure dry nitrogen being supplied thereto. The result is to fill the space above the oil with a as that is inert and to thereby remove all diinger from explosions by reason of the formation of exploslve mixtures that might otherwise exist.

In the modification shown in Figs. 3 and 4, a container 30, for deoxidizing material, differs from the container 13 of the apparatus shown in Fig. 1 in that it is cylindrical in form and is provided with a hollow bore, indicated at 31, that communicates with an opening 32 in the transformer casing. The container 30 is illustrated in the form of a sheet-metal member having perforations 21 therethrough. The valve 19 of Fig. 1 is diagrammaticall represented by a U-tube 33 of conventiona design. The operation of this form of my invention differs in no material respect from that of the form shown in Fig. 1.

In the apparatus shown in Fig. 5, the container 35 is rectangular in cross-section similarly to the container 13 of Fig. 1, but it is provided with a central bore 36, which corresponds to the circular bore 31 shown n Fig. 4.

n the arrangement shown in Fig. 6, two cylindrical containers 38 are employed, each of which corresponds to the container 30 of Figs. 3 and 4. A single controlling valve, such as the valve 19 in Fig. 1, may control the admission of air to the exterior surfaces of the containers 26. This arrangement differs from that of Fig. 4 principally in that a greater surface of deoxidizing material is presented to the incoming air, and the capacit of the respirator is increased correspon ngly.

Respirators constructed in accordance with my invention com rise few and simple parts which may be rea ily assembled and in which the deoxidizing material may easily be replaced when desirable or necessary- The removal of the bottom plate 12 permits the used material to be discharged. The respirator is so arranged that the air or gases passing therethrough traverse a path of minimum length but of large cross-sectional area whereby the resistance to exchanges of air between the transformer and the atmosphere is very sli ht.

The deoxidizing material is very closely adjacent to the space above the oil and the air initially within the transformer tank is readily deoxidized by diffusion. The respirator occupies very little space radially of the transformer and this feature renders our improved device peculiarly adaptable for use in connection with transformers of the radiator type wherein space is limited.

We claim as our invention 1. In a deoxidizing apparatus, the combination with a casing having a plurality of openings, of a perforated container for deoxidizing material so disposed in' said casing that any fluid exchanged between said openings must traverse said container.

2. The combination with a tank having fluid enclosed therein, of, a deoxidizing apparatus com rising a container for deoxidizing mate ria having one surface communicating with the tank and another surface communicating with the atmosphere, and a valve for automatically controlling the communication with the atmosphere.

3. The combination with a tank of a casing communicating therewith an the atmosphere, a perforated container for deoxidizing material in said casing having side walls spaced from said casing and respectively communicating with said tank and said atmosphere.

4. The combination with a tank having a fluid enclosed therein, a respirator connected to said tank, said respirator com risin a. casing, a perforated container for eoxi izing material having surfaces communicating ony with said fluid and with the atmosphere, and means for permitting a transfer of fluid between the tank and the atmosphere under redetermined pressure conditions.

5. The combination with a casing, of a. container for deoxidizing material therein, said container having certain portions spaced from said casing and certain other portions sealed to.said casing whereby the container divides the space within said casin 6. The combination with a casin of a container for deoxidizing material sposed longitudinally therein to divide its space, said casing having openings for respectively communicating with the sides of said container whereby fluid traversing said openings passes through said container.

7. The combination with a casing of relatively small transverse cross-sectional area,

' with' of a container for deoxidizing material dis- 8. In combination with a tank partially filled with oil and having a gas-filled space therein, a breathing apparatus comprising a casing provided with a porous container and means 1n said container for deoxidizing said gas when said gas passes into said space.

9. In combination with an oil-filled tank, having a gas-filled space therein, a breathing apparatus com rising a casing, means for permitting exha ation from and inhalation into said space, a porous partition in. said casing in contact with the gas in said space on one side thereof, and communieating with atmospheric air on the other side thereof, and means contained between the outer walls of said partition for deoxidizing inhaled gas.

10. In combination with an oil-filled tank having a gas-filled space therein, a breathing apparatus comprising a casing, means for permitting exhalation from and inhalation into said space, a porous partition in said casing in contact with the gas in said space on one side thereof and communicating with atmospheric air on the other side thereof, and a mixture of oxygen reducin chemicals between the outer walls of said partition.

In testimony whereof we have hereunto subscribed our names this 22nd day of September, 1923.

CLARENCE J. RODMAN. LELAND H. HILL.