Слике страница
PDF
ePub

(b) If the total pressure drop from the ash-pit to uptake remains constant, the pressure drop through any portion of the gas path will vary in the same direction as does the resistance to the flow of the gases, although the magnitudes of the variations may not necessarily be in simple proportion. Suppose the total pressure drop is 0.50 inch of water and the drop through the fuel bed is 0.25 inch, if the total drop be kept constant, but the resistance through the fuel bed be increased to about 0.32 inch of water; or if, for the same total drop, the resistance of the fuel bed be increased by quadrupling the thickness, the drop through the bed will increase to about 0.40.

(c) When the resistance through any portion of the gas path remains constant the weight of gas passing through this portion varies with some power of the pressure drop through this portion. Thus, since the resistance of that portion of the gas path from over the fire bed to the uptake is generally nearly constant, the weight of gas passing through the furnace and boiler varies as some power of the pressure drop between these points. It has been determined by experiment that the weight of gases passing through the boiler is, approximately, directly proportional to the square root of the pressure drop through the boiler or through any other portion of the gas path having constant resistance.

In order to obtain economy, the “ draft” must be a subject of daily discussion and study. Every officer and man on board ship must be made to understand what “ draft” is and how to use it. Ex scientia tridens.

THE TIME-FIRING DEVICE The use of the time-firing device was made standard for all steaming watches. Individual ideas of operation were not allowed and the rules laid down had to be followed at all times. The time-firing device and its purpose was explained to the officers and men. It was found that in order to be of real value cooperation from the bridge was necessary. Accordingly, instructions for its use were given to the deck officers and it was explained to them how they could assist. Any signals of change of speed were sent at once to the engine-room, including use of speed cones by ships ahead, and it was endeavored to anticipate speed changes if possible. The officers of the deck also kept the engineroom informed of matters of interest and the men on watch were

thus shown consideration. For instance, results of target practice, “How many hits did we get," were sent below as well as on deck.

In the use of the time-firing device the officer of the watch was required to anticipate needs for steam; for instance, if the evaporators were to be secured at 10 p.m., the time-firing interval should be increased at 9.45 p. m.

STANDING WATCH The officer of the watch was required to spend the most of his time in fire-rooms. It was found that at least half of each hour had to be spent there in order to obtain an economical watch. He was also required to inspect the feed-water heaters twice each hour and if the temperature of the feed fell below 230° F. something had to be done; for instance, pump bilges and obtain a little more back pressure. The proper use of pumps and auxiliaries made it possible to carry a back pressure of from 26 to 35 pounds gage and a feed-water temperature of from 242° F. to 250° F.

The officer of the watch was furnished complete information of all standing orders, cut-off settings, tank capacities and as far as possible what changes he might look for during his watch.

In order to reduce the time the furnace doors were opened at each firing, operating gear was fitted to them. Firemen, third class, were detailed to work this gear and the officer of the watch marked these men as well as the other men of his watch. Each watch (every man on watch) was marked on regular scale.

OFFICE WORK

A board was hung outside the office and each day the average marks for the watches were posted. About once a week the marks of the men were posted. This board also furnished information as to the coal used by each watch, the total coal and the total water used for the day and the engineering multiple—first, for the day; second, for the month; and third, for the year to date. This multiple gained about .043 every day for six months. The board held a large E and the words “ Fire light, fire often."

The performances of the other ships were posted whenever obtained

The standing of watches was systematized and made rigid. In other words, the men were able to tell at least two weeks ahead of time when they would have auxiliary watch. The auxiliaries, such as ice machines and evaporators, were given their special details. These details were never changed and, it may be said that properly supervised, of course, they ran their own watches.

The men of the engineer's force knew that all vacancies of higher ratings would be filled on board ship. This further enhanced the values of the marks given each watch, and it was but a short while when the men fully realized it. It further increased the interest the men took in their work.

The office avoided as far as possible work out of working hours. The men were made to realize that so long as they worked during working hours their time off would not be disturbed.

Officers were on their stations during working hours, in port or at sea; and in addition to merely being around, they answered questions, they guided the men in their work, and were of genuine value. This reduced the time required to do things. In connection with cutting down time required, the telephone system was kept up and used. The senior assistant was always available and the men were made welcome in telephoning him for advice, reports or information desired. The desire to do things in the easiest and quickest way seemed to prevail and a real genuine “ bound to win ” spirit developed.

[ocr errors][merged small]

(COPYRIGHTED)
U. S. NAVAL INSTITUTE, ANNAPOLIS, MD.

THE UNITED STATES COAST GUARD: ITS

MILITARY NECESSITIES
By CAPTAIN F. S. VAN BOSKERCK, U. S. Coast Guard

FOREWORD The following paper was prepared several months prior to the outbreak of the present war, but it has been impracticable to print it until now.

The fact has become apparent that in the past the navy and the coast guard have not gotten sufficiently close together, but it is thought that from the beneficial results attending present association, each service will have appreciated the worth of the officers of the other, to the mutual advantage of the two services and the public interests.

Since mobilization, the enlisted personnel of the coast guard has increased until it now numbers about 6000 men–2000 more than on a peace basis-and many changes have transpired as to the disposition of the entire personnel, which is now scattered among coast guard ships, naval vessels, at air stations, in Washington, and in the several naval districts, and the need for experienced officers has been urgent.

It is suggested that now is the psychological moment to make a mental survey of conditions, to take a look at them from a fair, unbiased viewpoint, and thus to realize the errors of the past, brought about as they have been by misunderstandings and a lack of knowledge of facts.

THE AUTHOR This paper has been written with the single idea of presenting to the officers of the navy and coast guard tentative suggestions for increasing the military efficiency of the latter service, which, if adopted, would be in the best interests of the navy and the

« ПретходнаНастави »