US1497197A - Protective device for autogenous apparatus - Google Patents

Description

June 10, 1924. 1,497,197

H. w. c. scHR6DER PROTECTIVE DEVICE FOR AUTOGENOUS APPARATUS Filed Aug. 18, 1921 HTTO/P/VEKF Patented June 10, 1924.

UNETED fiTATES snares rArENT curios.-

ANDEB IBERNEABD naliena, or FINKENBERG, LUBncx, enema.

rno'rncrrva nnvrcn non ao'roennocs nrrnm'rus.

Application filed August 18, 1921. Serial No. 4:93AM.

To all whom it may concem Be it known that I, HANs WILHELM Gums- TIAN Sonniinnn, a German citizen, residing at Lubeck, Germany, have invented certain a new and useful Improvements in Protective Devices for Autogenous Apparatus for which I have filed an application in ermany May 2, 1918, which resulted in useful Design Patent No. 7 20,304, registered Octome her 18, 1919), of which the following isa A specification.

In using autogenous apparatus for welding and cuttin metals which are worked by diflerent kin s of gases, e. oxygen and is another combustible gas, exp osions of the steel cylinders or steel containers, and of the fittings attached thereto frequently occur. The cause of such explosions can onl be ascribed to the fact that owing to the o okm ing. up of the mouthpiece of the autogenous burner, one of the gases passes over into the suppl pipe for the other gas and conse quent y there is formed in this supply pipe under some circumstances as far as the steel aa cylinder, a dangerous mixture of the gases. Or such dangerous mixture may be already present in the steel cylinder owing to the latter having been wrongly filled with the result that the mixture is passed out into the supply pipeleadingto theburner. If under such circumstances the flame of the burner strikes back, the mixed gas present in the supply pipe will become ignited with the result that in most cases an explosion in the piping 36- or in the steel cylinder follows.

The object of the present invention therefore is to provide a protective device or.

cartridge by means of which all the disadvantages above mentioned are avoided. This 40 is attained by interposing in the gas pipe a non-return valve and between the latter and the burner, in addition to the non-return valve, an explosion resistance in the. form of a plate or disc ofa fireproof m'a-a as terial such as sandstone, earthenware, fire clay, magnesium oxide, or the like, which, when the flame burns inwards, does not fuse or sinter, and so stops the explosion wave. And with this end in view my invention consists in certain novel features of construction and combinations of arts as will be hereinafter described and pointed out in the claims with reference to the accompanying sheet of drawings in which is shown an example of the invention.

Figure 1 shows in elevation an oxy-hydrogen weldmg apparatus fitted up accord- 111%!20 the present invention and lgure 2 1s a longitudinal section, on a larger scale, of a protective cartridge constructed according to this invention and inserted 1n each of the two gas supply pipes.

Like reference letters indicate like parts.

As shown in-Figure 1 the welding apparatus consists of an oxygen cylinder 0. and a hydrogen cylinder a each being provided with a pressure reducin valve 6 and I) respectively, a protective ilevice c and c and a flexible pipe d and (1 both of which lead to a welding burner e. In this latter there takes place, in a special mixing chamber in front of the outlet opening of the mouthpiece, a m1xture of oxygen and the other combustlble gas, which in this case is hydrogen. Now if while the apparatus is bemg used, the opening of the mouthpiece of the burner becomes wholly or artially choked up owing-to the entrance 0 dirt or llqllld metal, a mixture of the two gases may pass into one or other of the two su ply pipes d or d, the gas which is under tiEe lgher pressure passing over into the supply pipe for the gas which is under the lower pressure. According to the magnitude of the diiference between the pressures this mixed gas will flow back into the pressure reducing valve appertainin to the said suppIly pipe and even on into t e steel cylinder. nder such conditions, if the flame should strike back inthe burner, the mixed gas in the supply pipe will be exploded, and if any of said mixed gas is present in the ressure reducing valve and the steel 0 lin er, the contents of the latter also, will caused to ex lode.

n order to keep any mixed gas which p ay have been formed,'away from the corresponding pressure reducing valve and steel cylinder, and to intercept and render harmless expolsion waves of this mixed gas resulting from the striking back of the flame-from the burner, there is located in each gas supply pipe, a protective apparatus or cartridge 0 and c, the cartridge, in each instance, 1s preferably positioned between the supply pipe d or d and the pressure reducing valve 5 or b respectivel, and is therefore always located upon t e low pressure side of the reducmg valve. As the structural form or both the cartridges 0 and o is the same, the illustration and description of only one of the same e. g., the cartridge 0 will sufice for the comprehension of the invention. This device consists of a cup-shaped cartridge case 0 see F igure 2, provided Witha non-return valve f, acted upon by a spring 7, and a connecting screw thread 9 n the gas inlet nozzle k, a sleeve c' containing a ,orous fireproof protective disc k of magri sium oxlde inserted gas-tight therein, and a cartridge cover m with a connecting screw thread a on the cup shaped gas outlet nozzle 0. By screwing the parts 0 and m to ether the protective disc 2', la, is clamped rmly and the joint-made gas-tight by the interposltion of annular packing discs or washers Z, so that all the gas which passes through the pi e and the protective cartridge is compe ed to pass through the protective disc or plate is, which as regards its porosity, is of such a nature that itallows gas to pass'through it in both directions. The gas when flowing in the right dlrection opens the non-return valve f and then flows through the protective plate I: to the burner. Any gaseous mixture passin back in the reverse direction through t e protective plate is however immediately stopped by the non-return valve f which automatically closes and cuts 03 the mixture so that it cannot get into the pressure reducing valve and the steel cylinder. Furthermore the protective plate It stops any explosion wave coming from the burner on its front surface, so that the non-return valve is not touched by the explosion wave and if any mixed gas should be contained in the pressure reducing valve and the steel cylinder this gas cannot be ignited. The flame on the contrary goes on burning at the front face of the protective late until the mixed gas present has burned out or'unti'l the stop valve or the pressure reducing valve is closed.

Without the non-return valve f the rotective plate is would, as can be seen, a 0rd no per tion of the gas mixture into the pressure reducing valve and the steel cylinder, and on the subsequent use of this cylinder for other purposes an accident might easily happen. The combined provision of a nonreturn valve and of a protective plate which stops the explosion wave and is composed of porous, fireproof material, such for example as ma esium oxide, sandstone, or the like, o era the greatest protection ect safeguard against the penetra t eater against the dangerous effects ot the bachward how of the gas, formation of mixed gas and striking back of the flame.

The manufacture of the protective discs or plates may be conveniently carried out by mouldin the plates from a mixture of granulated hreproof material such as sandstone, magnesium oxide, fire clay, etc. and granulated combustible material, e. g. coal dust, or the like, and then afterwards burning them. By so treating the plates thus prepared the combustible terial burns awa and thus the necessary porosity is provided which latter can be related by the porportion selected for the mixtures.

The increased resistance which is natural- 1 produced by the non-return valve and the porous protective plate, but which is in itself very small, can be easily overcome by a moderate increase in the pressure off the oxygen and also of the hydrogen. Protective plates which become defective can be easily replaced by spare plates.

It is preferable to provide such a protective cartridge for eac of the two as pipes d and al but in any case one s ould be provided for the pipe which supplies the gas at the lower working pressure. Instead of being placed on the ressure reducing valve the protective cartri ge may be placed on the burner. It may also be made in two parts and the part which contains the protective plate mounted on the burner and the CID part which contains the non-return valve on the pressure reducing valve.

I claim:

1. A protective device of the hind d scribed comprising an inlet nozzle, a cupshaped case at the outlet end thereof and comprising an integral part of said nozzle, a non-return valve in said inlet nozzle between its ends, an outlet nozzle detachably connected with said case, and a flame-arresting discclamped in said case by said outlet nozzle and obstructing the axial passage through said device. I

2. A protective device of the hind described comprising andnlet nozzle, a cup shaped case at the outlet end thereof and comprising an integral part of said nozzle, a non-return valve in said inlet nozzle between its ends an outlet nozzle detachably connected with said case, a sleeve clamped in said case by said cup-shaped outlet 111041- zle, and a porous disc of fire-proof material fixed in said sleeve and obstructing the axial passage through said device.

HANS WlLllllElLl (ClllllSTllAll @Cllilfltlllllill, Witnesses:

Fnmx Jonrrocronrn, lEm/mn A. H. L. Mmtrmmorn Tilt)

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