AS

S a preamble to this paper, a better one perhaps could not be written than the article on standardization appearing in Bulletin No. 29, of October 4, 1913, issued by this association. Lest it may not have been read carefully by some, or partially forgotten, it is deemed well, with the permission of the author, to repeat it here. It is as follows:

"In looking over the reports of the work done by associations simliar to ours, it is a noticeable fact that they have done considerable towards standardizing certain parts of their product. There is no greater field or better opportunity for good work than standardizing certain parts of the gas engine; neither can any good excuse be given for not doing so. A great many engine manufacturers use the same type magneto, battery, spark coil and spark plug, the same make switch or other accessories; why, then, not use the same size valve with a standard size stem, a standard size crank shaft and connecting rod, and standard bolts with standard threads? It is going to be a wonderful help in cutting down the cost of material in your engine."

It was but a few years ago that the automobile manufacturers took up this matter through the Society of Automobile Engineers and standardized certain parts. There is no question but it has been of great benefit to them. Is not the gas engine industry just as an important one; has it not been of as much benefit to mankind as the automobile? We recently had a talk with one of the engineers from one of our largest valve manufacturers and he states that there was no question but at least twenty-five per cent of the present cost of valves could be saved were they but of a standard size. Does this mean anything to you, Mr. Gas Engine Manufacturer?

There is work for the magneto manufacturer along the same line, adopting a standard size shaft with either a taper or straight end, and a standard distance between the bottom of the base and the center of the shaft.

This would be of great assistance to the manufacturer as well as to the user. It would lose you no accounts as the magnetos furnished to automobile manufacturers have been standardized in this way.

It might be added, that it would not only enable you to save money on parts at present made by yourselves, but it would introduce highly trained and experienced specialists, the executives and employees of the various accessory manufacturers, as a part of your shop organization,

Paper read by Wm. H. Spire, M. E., at the annual meeting of the National Gas Engine Association at Toledo, Ohio, December 4, 5 and 6.

thus placing you in a position to produce a higher grade machine, both as regards material and workmanship. It is reasonable to suppose that if all of you use practically the same thing for any one part, the manufacturer of that line can afford to equip with dies, jibs, fixtures and possibly special machinery that will make the product quickly and correctly, while if each of you use something a little different, he cannot afford to take your business on account of the small volume and the low price he has to make to get it, or, if he does, he cannot afford to equip properly to do the work. This, of course, does not apply to those concerns who order parts by the thousands. If the quantities are large enough almost any parts manufacturer will make anything, still he would be able to do better if they were standard, and you would save by so making them. You have to pay for the fixtures or dies at any rate, so it would be cheaper to have their cost distributed over the whole field rather than for each of you to pay for a set of fixtures for the same part, differing only slightly from some others. So much for the benefits to be derived.

That which follows is not intended to be all a perfect idea, but only a few suggestions set down to start you thinking and open a discussion which it is hoped will lead to something.

As in all things of this kind, it is best to start at the beginning, so perhaps the first thing that should be considered is the rating. There seems to be almost as many different B. H. P. ratings of engines of the same bore and stroke, when using the same fuel, as there are builders of these same sizes. The automobile builders and sales agents experienced the same trouble when they tried to compare the power of the motor in one machine with that of another, and to overcome the confusion, the A. L. A. M. adopted a horse power formula, now known as the S. A. E. formula which is D2n divided by 2.5, where D equals diameter of cylinder, n equals number of cylinders, and 2.5 is a constant. This, today, is perhaps the best thing of its kind in existence, but still gives rise to much discussion because it does not take into consideration the question of r. p. m., at 1,000 feet piston speed. With this understanding the formula leaves but little to be desired, giving a fairly accurate value for the horse power of any high speed motor-accurate enough for all practical purposes and for comparison. Other formulas have been given by Roberts and the American Power Boat Association. Perhaps one of these formulas would suit your purpose and if so it should be adopted by the Association so that each builder starts at a com

mon point. If that could not be done, then a new formula should be worked out, and each of you work to that formula. No matter how you manufacturers rate your engines or what you say in regard to them, if you over-rate or under-rate the user will call your machine a 15-horse power or a 20-horse power, as you have called it on the name plate, but if it is over-rated he will say that the engine is "weak," or if under-rated he will say it is "strong" in comparison. The underrated machine gains the reputation, other things being equal, and the over-rated gets the "black eye." So it would seem well for you as an association to adopt some formula, or possibly other means by which all engines of the same bore and stroke at the same r. p. m. would have the same rating. Then, if by some fineness of design or workmanship one engine gives more power than another, charge it to efficiency and allow the builder to get credit in that way, as credit is certainly due him. This will probably give rise to some discussion regarding the fact that a builder of a highly efficient machine will be compelled to sell in competition with a cruder machine, on account of the same rating, while under the present system he can "boost" his rating a little and get a little better price without any argument as to efficiencies. Under the standard rating perhaps there would be some difficulty at first, but it would last but a very short time.

Along this line, why would it not be well to standardize the speeds? That is, a certain size engine for a certain class of duty, of any make, would run at the same speed as the same size engine of any other make. You might say that in so doing the manufacturer would lose his individuality, but in answer, the case of the steam engine is cited. Steam engines, for a certain class of duty, all run at practically the same speeds, yet there is a marked difference in their design and action. Of course, there are the highspeed automatic and the low-speed Corliss, but each has its own field and thus it seems that combustion engines could be divided into some such classes with reference to the duty for which they are intended, perhaps one scale of speeds for marine engines arranged according to size, another for stationary engines and another for tractors.

It has been the writer's pleasure, within the last three or four years, to buy a number of threephase 60 cycle A. C. motors and it is very convenient to know that up to a certain size they can be obtained in three speeds, namely: 1,800, 1,200 and 900 S. r. p. m. with pulleys so that the belt speeds are practically constant. When prices are asked for one knows that each of the bidders is making a price on a machine to be operated under exactly the same conditions and it only remains to decide which will be the better for the purpose. Of course, in this case the speeds are predetermined by the current worked with but there

is nearly the same uniformity in the speeds of the D. C. machines at full load, although most any speed could be obtained.

In the above, regarding the alternating current motor, mention has been made of the pulley, which brings us to another part of the gas engine that might be well worth considering, namely, the belt pulley. The average belting practice is to run belts at a lineal speed of about twenty-five hundred feet per minute. Taking this, or some other figure that you may decide upon as a basis, and the standard r. p. m. as previously referred to, the standard diameter of pulley is fixed. It only remains to determine the width of belt, then the pulley is standardized. In connection with this width it might be well to consult with builders of machinery operated with your engines and arrive at a conclusion satisfactory to all, unless you feel that by publishing your standard data they will use it in determining their sizes. By standardizing the pulley, you perhaps would not make a saving nor do anything beneficial for the accessory makers, but you would make it very convenient for your users.

Closely connected with the pulley is the crank shaft. Having standardized the bore and stroke, it would be a very easy matter to standardize the form of the cranks, the crank pin, and bearings for each horse power in each class and allow the builders to exercise their refinements in the kind of material used and the forms outside of the bearings. Thus drop forge concerns could have standard dies for the various shafts and by forming the ends under the Bradley hammer or otherwise, could name you attractive prices, even in small quantities. So also could a standard relation between stroke and length of connecting rod be established, and a standard end for the wrist pin, thus enabling you to obtain these drop forged, practically from stock.

The piston pin and bosses could be standardized so that the pins could be made by parts manufacturers, furnished hollow, to reduce weight, case hardened and ground, or of a tough oil hardening material treated and ground.

A very vital part of an engine are the poppet valves. There seems to be as many different ideas concerning their size, shape and material from which they are made, as there are engine builders. All of you cannot be right-some of you must be. There is no reason known why this part could not be made standard for each size engine of each class, as regards diameter and form of head and diameter of stem. Of course the length of the stem would have to vary. In standardizing this part you would enable the manufacturer to carry a line of stock forgings which he could make in quantities, thus cutting down their cost to such an extent that he could afford to make prices low enough to make it attractive to the engine builder, at the same time giving you quick service in the matter of

delivery. As an illustration of the diversity of design, we have about one hundred and fifteen sets of drop forging dies for valve heads to take care of the automobile trade, besides thirty automatic screw machines, making heads from the bar for those valves not covered by the forging dies and for small lots. For the same reason we have about thirty-five gated patterns to take care of the cast iron head business and are constantly making single patterns to take care of forms and sizes that cannot be gotten out of these gates. More of this part later.

Much also could be done with the springs. Perhaps two forms should be adopted, one an ordinary straight coil spring and the other the conical coil. It seems possible that their length, diameter, size of wire and tension for a certain compression could be standardized so that a very few sizes would suffice for the whole line from the smallest to the largest valve.

Another part worthy of your consideration is the spark plug. The jump spark plug is already standardized by the S. A. E. and is all that could be desired, but the make and break plug is of a multitude of sizes and shapes. Perhaps the whole plug cannot be standardized-it would be well if it could, but at least the electrodes can, and the following is a suggestion: Make the distance between center of electrodes a standard; the size and shape of the heads and the diameter of the stems a standard, then if the whole plug cannot be standardized, the electro forgings could be carried in stock of sufficient length to take care of the longest plug and cut for any other length at but a small cost.

Horizontal engines use a push rod to quite some extent for operating the valves, as also do the vertical engines with valves in the head operated by rocker arms, in which use is made of a yoke at one end and an eye at the other, or eyes or yokes at both ends. It is now the custom to tap the eyes or yokes and assemble them with lock nuts. This is expensive and is not as good as could be. Adjustment is required in these parts so one threader connection must be had; that being sufficient for all purposes. The idea is to standardize the eye ends and the yoke ends or adopt some present forms as standards so that they can be drop forged in quantities and then weld them electrically to the rods.

In the matter of screws and screw thread there are two standards already in existence which fill the requirements admirably, namely the United States standard and the S. A. E. standard, which is very similar to the U. S. standard, except that the threads are finer but of the same form. Many makers still adhere to the old V thread and small head screws, although the U. S. S. thread and head have been in existence for a number of years. There is really no V standard. Each tap manufacturer has a standard of his own. Το prove this, just order a standard "V" male or fe

male plug gauge from some reputable small tool manufacturer, such as Pratt & Whitney, and they will be almost sure to ask you for your formula for the thread. It is urged that you adopt both the U. S. S. and the S. A. E. standards, using the U. S. S. for ordinary purposes and the S. A. E. where stronger threads are required or on parts subject to much vibration. The heads on the screws are larger than on ordinary screws, and there is a reason for it. One is that you get a greater bearing under the head and the other is that the wrench will fit a nut of a certain size screw, will also fit the head, besides making a much better looking screw and giving a more finished appearance to the machine. U. S. S. screws cost slightly more on account of the increased amount of stock, as well as being harder to make, but you, who furnish a set of wrenches with your machine, as most of you do, can more than cover this extra cost in the saving of wrenches.

After all this talk, perhaps you wonder why I, an employee of a firm not in the business of making internal combustion engines am so interested in the subject of standardization, so with your permission I will tell you.

First, I am interested as an engineer. Engineers, as a rule, you know, delight in tabulating and plotting curves for all conceivable things, sometimes much to their own advantage -often to no apparent advantage and at no little expense to the firm which employs them. Secondly, I wish to try to show through the products manufactured by our concern how you could improve your product by standardization in our particular line.

We are manufacturers, by the electric welding process, of the larger sizes of United States Standard head cap screws and coupling bolts, special screws and bolts of larger diameter than one-half inch and longer than two and one-half inches, of any material, annealed, heat treated or case hardened. Poppet valves of any material or combination of materials, either in blank semi-finished or machined and ground complete make and break spark plug electrodes push rods, completely finished, hardened and ground; piston pins, hardened and ground, or any other special parts where it is desirable to have a forging of some odd shape integral with a straight stem of any form, such as round, square or hexagon, or forgings welded together, which otherwise would make an almost impossible drop forging job; or a part of large diameter, the product of a screw machine, to a stem of any form, or the union of most any two dis-similar metals, including copper and brass.

With your further indulgence I would like to say a little about each of these products. First, we claim for our screws, besides the advantage of the large head mentioned elsewhere, that they are stronger and of better finish than any milled or