US2357647A - Gas burner - Google Patents

Description

P 1944- R. J. GREENE 2,357,647

GAS BURNER Filed Jan. 15, 1942 Patented Se t; 5, 1944 2,357,647 GAS BURNER.

Raymond J. Greene, Sebring, Ohio, assignor to The Gem Clay Forming Company, Sebring, Ohio, a corporation of Ohio I Application January 15, 1942, Serial No. 426,888

6i Claims.

The invention relates to burners for burning natural or manufactured gas in appliances of various types, and more particularly to a burner of this general classification formed of clay.

Under present practice cast iron is the accepted standard material for the manufacture of gas burners for use in appliances such as gas fired heating stoves, water heaters, oven burners, certain types of furnaces and the like.

However, due to thepresent emergency, the amount of cast iron obtainable for civilian uses has grown exceedingly small and may be cut off entirely and the manufacturers of gas heated appliances are faced with the problem of finding a substitute for cast iron, for the production of burners for such appliances.

Furthermore, cast iron burners have certain objectionable features which are overcome by the use of clay for producing such burners.

Du to the method by which they are necessarily produced, cast iron burners have several serious faults which not only reduc the efliciency oi the burners but also result in considerable waste in the production thereof.

The cores used in the casting of the burners cause the most serious problems. The interior surfaces of the burner, produced by the core, are naturally very rough, cutting down the flow of gas therethrough, and impairing the efficiency of th burner.

Furthermore, the cores have a tendency to float, or shift, and in so doing frequently disturb the entire inside contours of the burner, throwing the gas channel out of shape and resulting in considerable waste. It is common for cores to float or shift to such an extent that surrounding wall thickness, which normally should be onefourth to one-eighth inch, is reduced to almost paper thickness on one side while the opposite side is nearly twice the normal thickness.

Where manufactured, or coke, gas is used for fuel the naturally high sulphur content of such gas causes a cast iron burner to corrode very rapidly, thereby closing off the flow of the combustible gases to the flame zone of the burner, this corrosive action being particularly rapid in slotted type burner.

This condition is so serious that at least one city places a restriction upon the use of slotted type. cast iron burners, and permits the use of drilled port type burners only because the corrosive action does not take plac quite so rapidly A in the series of small holes in this type of burner as it does in the long slots of the slotted type burner, and it is therefor a Another fault inherent in cast iron burners is thatdue to absorption qualities of the metal, the higher temperatures maintain and build up regardless of whether th burner is turned to high flame or low flame, and this results in overheating of the body of the burner by conduction, and the effect of high temperatures of the head and the mixer tube combine to retard primary air injection.

Due to this temperature change in the body of the cast iron burner affecting the normal mixture of fuel in th combustion chamber, it is neces-' sary, when using a cast iron burner, to adjust an appliance with a normal rating of 50,000 B. t. u. to as high as 57,000 B t. u.,- cold start, in order to obtain, in approximately fifteen minutes, its normal rating after heat hasbeen built up.

It is an object of'the present invention to overcome the above mentioned and other difficulties and faults in burner construction and operation by producing a clay burner which may be produced at a fraction of the cost of a similar cast iron burner.

Another object is to provide a gas burner formed of a special clay composition which will meet the requirements necessary for a commercially practical gas burner.

A further object of the invention is the provision of a clay gas burner produced in such a manner that the interior surfaces of the burner are smooth and the wall thickness of the burner is uniform.

A still further object is the provision of a clay burner in which the body portion of the burner will remain relatively cool while the burner head is operating at maximum temperatures.

Another object of the invention is the provision of a gas burner formed of material which will not corrode and clog up the burner openings when manufactured or coke gas is used for fuel in the burner.

Th above objects together with others which will be apparent from the drawing and following description, or which may be later referred to, may be attained by constructing the improved clay burner in the manner hereinafter described and illustrated in the accompanying drawing in which Figure 1 is a perspective view of one form of clay gas burner embodying the invention;

Fig. 2, a perspective view of one-half of'a clay burner which has been pressed in dies preparatory to attaching the same to a similar burner half before the drying and burning thereof; and

Fig. 3, a longitudinal sectional view through a mold showing the manner in which the improved clay burner may be molded from slip."

Similar numerals refer to similar parts throughout the drawing.

Although the invention is applicable to many forms of gas burners for use in heating stoves, hot water heaters, gas range ovens and some forms of gas furnaces, for the purpose of illustration it is only thought necessary to show one form of burner for the reason that in carrying out the invention the general contour and arrangement of cast iron burners now in use may be substantially duplicated in the clay burners to which the invention pertains.

The type of burner illustrated comprises generally the hollow tubular body I having at one end a bell I I through which the air and gas mixture is admitted and at its other end a T-head I2 provided with a plurality of transverse slots I3 through which the mixture is admitted to the combustion zone.

Within the hollow body III of the burner the gas channel It forms communication between the r bell I I and the hollow burner head I2. In the production of cast iron burners a core is utilized for producing the gas passage I4 and the hollow interior of the head I2, and the interior surfaces of the burner left after removal of the core are naturally very rough, interfering with the prope flow of gas through the burner. I

Another difllculty encountered in the manufacture of cast iron burners is the tendency of the core to float or shift during the casting operation, and in so doing disturb the entire inside contours of the burner. A very material loss is experienced from thisfault, which in the majority of cases does not become apparent until the cast iron burner has been completely processed, assembled and installed in the appliance for actual burning tests.

It-is quite common for cores to float or shift to an extent where the surrounding wall thickness of the burner, which should be about one-eighth to one-fourth inch, depending upon the style of the burner, will frequently be of substantially paper thickness on one side while the opposite side will be substantially twice the normal thickness.

As a result of this casting method the efficiency of the burner is impaired and considerable loss is experienced by the production of burners which cannot be used.

The present invention contemplates the production of gas burners from a clay composition by methods which eliminate the manufacturing difficulties as well as the operating faults of the burner.

Experience has shown that a gas burner formed of a composition of talc, alumina oxide, Georgia china, Florida china clay and Tennessee ball meets the rigid requirements for gas burners and overcomes the manufacturing difliculties and operating faults inherent in cast iron burners.

It has been found that gas burners may be formed of clay by either of two manufacturing methods, each of which produces a burner which overcomes all of the above mentioned faults common in cast iron burners and which operates more efficiently than the cast iron burner of the same design.

As shown in Fig. 2, the burner illustrated in Fig. 1 may be formed of two similar halves, pressed into the desired shape in dies of suitable construction, the two halves of the burner, while still green, being then stuck together by moistening the opposed surfaces and pressing them tightly together, as in usual practice in the pottery industry, after which the completed burner is dried and fired in a kiln in usual and well known manner.

Such a construction of burner has uniform wall thickness, since there is no core to shift or float within the same as in the making of a cast iron burner. Furthermore, the entire inner contour of the burner is much smoother than the interior of a cast iron burner since the plastic clay mass is pressed or squeezed into shape within the dies. This provides for a better flow of gas through the burner and contributes considerably to better burner combustion.

Clay burners made in accordance with the invention have been subjected to all of the tests to which burners are subjected in handling and use and have been found to be superior to the cast iron burners in every respect excepting that the tensile strength of clay is naturally not as great as that of cast iron. However, this is not a drawback as tests have shown that the tensile strength of these clay burners is more than sufficient to meet all of the appliance shock tests and handling tests to which burners are ordinarily subjected.

These clay burners may be used to burn manufactured or coke gas more satisfactorily than cast iron burners as the sulphur content of such gas will not produce any corrosion and consequent clogging up of the burner openings of a clay burner. When these clay burners were operated so that the burner head reached a temperature of 440 F. the body of the burner remained sufficiently cool that the same could be held in the hand. Carrying this test farther, and providing a shock test for these clay burners, the head of the clay burner was heated over a Bunsen flame to incandescence, at approximately 1200" F., and the body and base of the burner still remained sufficiently cool to permit their being pickedrup by hand.

After heating the burner head to incandescence, as above stated, the entire burner was immediately immersed in cold water and after being cooled and removed from the water the burner showed no sign of fracture. The same held true when the burner head was heated to incandescence and then gradually cooled by slowly drippling cold water upon the highly heated burner ead.

Instead of forming the clay burner by pressing a plastic mass of the clay by the dies, as above described, a slip or creamy liquid solution of the clay composition may be poured into a two-part mold I5 as shown in Fig. 3 and permitted to stand for a few minutes until a coating of a solid formation of the clay has formed upon the inner walls of the mold to the desired thickness when the mold may be inverted as in usual practice and the surplus slip" poured therefrom, after which the green clay burner is dried and fired in a kiln. It has been found that clay burners formed in this manner have an interior surface even smoother than those formed by the method illustrated in Although the proportion of the various clays in the mixture may be varied very good results have been obtained by either of the following formulas:

Formula #1 I prefer to use the ingredients in the proportions given in Formula #2 above.

I claim:

1. A gas burner formed of a composition comprising 18.11 per cent of Tennessee #9 ball clay, 23.9 per cent of magnesia silicate, 17.97 per cent of Georgia china clay, 14.7 vper cent of Florida china clay, 20.12 per cent of alumina oxide, and 5.2 per cent of calcined Georgia china clay.

2. A gas burner formed of a composition of 18.11 per cent of ball clay, 23.9 per cent of talc, 32.67 per cent of china clay, 20.12 per cent of alumina oxide, and 5.2 per cent of calcined china clay.

3. A gas burner formed of a composition comprising about 18 per cent of Tennessee ball clay, about 24 per cent of magnesia silicate, about 18 per cent of Georgia china clay, about 15 per cent of Florida china clay, about 20 per cent of alumina oxide, and about 5 per cent of calcined Georgia china clay, said burner comprising an integral hollow body and burner head, each having walls of uniform thickness and smooth inner wall surfaces.

4. A gas burner formed of a composition comprising about 18 per cent or ball clay, about 24 per cent of talc, about 33 per cent of china clay, about 20 per cent of alumina oxide and about 5 per cent of calcined china clay, said burner comprising an integral hollow body and burner head, each having walls of uniform thickness and smooth inner wall surfaces.

5. A gas burner formed of a composition comprising approximately 5 per cent of calcined china clay, approximately one-fourth of talc, approximately one-third of china clay and the balance composed of substantially equal parts of ball clay and alumina oxide.

'6. A gas burner formed of a composition comprising approximately 5 per cent of calcined Georgia china clay, approximately one-fourth of magnesia silicate, about one-third of a mixture of Georgia china clay and Florida china clay and the balance composed of substantially equal parts of Tennessee ball clay and alumina oxide.

RAYMOND J. GREENE.

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