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plants and the electrical method has been found to make steel cheaper than the crucible method. We have not as yet been able to shut down any open hearth furnaces. One firm operated a Bessemer plant and solved the question of increase in producton by the installation of an electric furnace. It still operates ts Bessemer plant, however.

In answer to the first question regarding the rates charged to the special furnace load, I wish to state that it is entirely a matter to be decided by the power company, and will naturally depend on local conditions As far as the rate charged is concerned, a man having two pockets jomed together in the back can put money in on one side and take it out on the other, just as he desires. It is a question also of assisting the power company in loading up its generating equipment and that would naturally determine what amount the additional power adds to the expense of the power plant operation In the particular case mentioned in the report, the rates charged to the furnace company are sufficiently large to pay the regular dividends on the stock of the company, and I think the matter will be hand'ed in the same way in any company that organizes and operates a subsidiary load of this chara ter The man advantage of having such large furnaces of this character is that very small labor charges are involved in comparison with other manufacturing and, therefore, when the plant is shut down for repairs and loa! conditions, it does not add so enormously to the cost of the finished product

Mr Crosby brings up the point of being certam of what information is published in a report of this kind We have certainly tried to get some detrate inform at on for the report and to stir up some discussion, but if any data are not accurate and we can correct them, we shall be on's too glad to do It is absolutely necessary to have something she a! t'e reason I have given a list of electric firmakes is to make it possible for members who may be considering destne forma es to get in touch with as many as t'ey devre We tre! to art something in regard to the Rennertelt furnace, bet nothing in and we did not make any statements concerning it

Regarding price It is poss Me with the right and tins ta produce electric steel just as cheaply as it can be male by st

other methods; but, at the same time, you will find that there is a market and a much better price for electric steel.

Some data as to maintenance cost will be found in the tabulations given in the report.

Now, regarding the single-phase furnace operating off of a 3-phase system, the information received from Milwaukee tends to show that they have had more experience there along that line than in other cities, and I shall have to refer the gentlemen to the remarks of Mr. Gates on the subject.





MR. DRESSER (continuing): I have received since this report was printed a rather interesting, practical description of some of the work which is bemg done by one of the electric transportation companies of New York City Its outfit consists simply of a bank of ordinary car rheostats so arranged with circuit breakers and controlling switches that it is possible to regulate the current according to the class of work to be done.

"We have found it advisable, in conducting our welding operations, to place the actual work in charge of a skilled mechanic of the progressive type, as we are not familiar with any exact or comprehensive data on the various types of filling material and their adaptability for fusion with the different grades of metal to be welded The employment of a skilled operator makes it possible to conduct experiments continuously in order to get the best results under varying conditions

“We have used our electric welding outfit successfully in bending up worn rails, joints, frogs and other seal work, and repairing cracked or broken tracks, swit hes, cto, as well as in repairing all car body parts In making the above wells we have, of course, encountered many different grades of metal. each grade presenting its own peculiar condition which must be met in order to obtain the best results

"In general, we have found that on hard surtices, subrest to frictional wear, it is best to use a ligh carbon c'è trode that t'e use of a me li im carbon is advisable where the jirt is subiect to shock or bending strain (this rey "red tongdo often being a l'ed to by cooling in lime); and that good results can be ob tamed on surface halle to uneven expansion by the use of com non rd steel

"It is ex-re'

dun alt to formedte at s hird and fast


rules for welding castings, due to the numerous grades of material now supplied in various apparatus. In general, these should be welded with carbon electrode, using a good grade of soft steel or Norway iron.

"To sum up our entire experience with electric welding, we find that except as stated above, there can be no fixed rules laid down for the welding of various metals. Under the direction of a skilled operator, experiment will quickly determine the methods best suited to each particular job. There are practically no limitations to the types of welding that can be accomplished satisfactorily, and although the comparatively short period of time in which our plant has been in operation precludes an accurate statement of the amount of money saved by welding instead of renewing broken or worn equipment, there can be no doubt that the operation of the plant has saved the company a very considerable portion of its renewal costs."

I also have a letter from Dr. Stratton of the Bureau of Standards stating that the Bureau has received a number of inquiries in regard to the application of electric welding. I will read the letter in part: "The Bureau has not issued any publications in this important field but will be glad to receive suggestions along the lines which you may think suitable for it to undertake. We have had several inquiries regarding the improvement of the various aspects of electric welding and its adaptability to special problems, and would be glad to keep in touch with your Committee on this matter."

There is practically nothing I can add to the report, but I want to call your attention to the second appendix where details are given of installations and tests we have run upon our own system. In this appendix you will note a rather unique use of spot welding for annealing purposes. We are operating an automatic spring wheel factory which is annealing casehardened drop forgings in about four seconds apiece. The center is annealed while the outer circumference is untouched by the heat. The heat penetrates and is developed locally so rapidly that it does not touch this outer portion, but leaves the center portion of the forging soft enough to drill and tap easily.

MR. JONES: The matter of properly handling small welding loads has been quite a problem to most central station companies. This class of business presents rather severe service conditions.

The actual consumption is very small while the maximum demand is relatively large, and being intermittent in character Trequently causes serious line disturbance. While, therefore, the business itself is ordinarily not profitable, yet it should be handled in a broad minded way and its development not be discouraged as it helps to popularize the use of electricity. A basis of minimum charge should be established so that the supply company will get a reasonable return for the service rendered.

The welding equipment frequently requires a separate single pha e service. In cases of this kind an adequate return will not be received by simply combining the consumption on the welding meter with that of the general power meter.

case in mind where a large power customer insisted that he would need a capacity of 150 kilowatts in single phase service for some spot welders. After the service had been installed for a period of time it was determined that the actual consumption was about 100 kilowatt hours per month, the income from which for this particular installation was $t. This, of course, was by no means an adequate return for 150 kilowatts in transformers. One way to obviate this difficulty is to establish a minimum charge based on the kilowatts of transformer capacity required for the welding load; another way is to take separate contracts for this class of business, requiring minimum bills based on the connected load of the welding apparatus. The latter method has been put in operation in Chicago with satisfactory results.

Mr. A. W. YOUNG, Camden, N. J.: We have a number of installations and I would like to ask if anyone has had any experience with putting a welder in on a given size of transformer. How many additional welders can go in on that same transformer?

MR. E. A. OLTZ, Hammond, Ind.: Our experience with the spot welder has been exactly the same as that of Mr. Jones. They take a larger equipment in capacity and a very small a.. ount of current, as the load is applied in some cases for only a fraction of a second. We not only found them un; rot'alle, but, as they operate on single-phase and the lines were not constructed to carry that large load, they caused additional expense in fitting the lines to take care of it.

The instantaneous load applied is just enough to wart the

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