Display:

Results

Viewing 22231 to 22260 of 22505
Technical Paper
1939-01-01
EDWARD F. HARRISON
Technical Paper
1939-01-01
Ernest E. Wilson, Paul Huber
THE authors introduce their paper by outlining the various sources of noise existing in the motor car, together with some of the suppression means. Noise measurement, test methods, and the mechanism of the transmission of forces generated by the contact between the tire and the road to the body and frame are discussed. The authors state that, since these forces produce motion and deflection of the body, they are responsible for the road noise, and conclude that the proper approach to a method for suppressing road noise is through the structural design of the vehicle. They suggest, in the main, the localizing of stress to stress members, the raising of the resonant frequencies of the structure, the detuning of the suspension system, the body, and the frame, together with some isolation at selected points.
Technical Paper
1939-01-01
B. A. Yates
THE importance of the material of the piston ring has too long been relegated to the background as compared with such design factors as ring proportions, ring loadings, circularity, point pressure, and so on; therefore, this paper concentrates on the material factors - such as composition, structure, and surface finish - which should go into the modern piston ring. The causes of piston-ring wear are analyzed and classified under three headings - abrasion, corrosion, and erosion. Various types of coating materials, both metallic and non-metallic, employed to reduce the severity of scuffing or scoring, are considered. Test results are revealed that indicate that superficial coatings reduce piston-ring wear from scuffing and erosion, and that a very thin coating of tin was more effective than other types of metallic and non-metallic coatings.
Technical Paper
1939-01-01
J. B. Johnson
MAGNAFLUX testing has become an important adjunct in connection with the inspection of aircraft parts fabricated from magnetic materials. The method is very sensitive and may indicate not only defects which seriously weaken the part, but also non-injurious imperfections. The author has classified the several defects indicated by magnaflux which have been found in the routine inspection and examination of a large number of parts which have been in service in engines, airplanes, and accessories operated by the U. S. Army Air Corps.
Technical Paper
1939-01-01
Edmund T. Allen
THE organization, training, attitude, and esprit of the crew are all-important for successful flight-testing of large aircraft, Mr. Allen shows. These problems, he explains, are similar to those involved in the functioning of a military unit or of a city government. Choosing the required personnel of from 3 to 10 men fitted to their various duties, training and coordinating them, and building up an efficient unit for collecting accurate flight-test data under conditions of hazardous operation devolves upon the chief test pilot. Since flight-testing involves continuously extending the range of investigation of flight characteristics toward margins of safety, the principle of least hazard has been developed to guide all flight planning and all test operation. This least-hazard principle guides the testing of structure and functional systems through the initial flights, stability tests, performance tests, and flying qualities determination. The high cost per minute of test flying is another factor of extreme importance brought out by Mr.
Technical Paper
1939-01-01
Paul S. Lane
PISTON-RING irons are not the “best-wearing” irons, contends Mr. Lane in his discussion of bore wear from the standpoint of the materials commonly used for high-speed automotive diesel and aircraft-engine cylinders, liners, and rings. Measured on a weight-loss basis under direct comparison with other conventional iron structures, piston-ring irons normally give relatively high weight-loss figures. But piston-ring irons do have the significant and desirable faculty of wearing away with very little tendency to accumulate wear products on their rubbing surface. In fact, this ability is probably of equal or greater importance than actual low weight loss. In his paper Mr. Lane reports the results of several years of laboratory wear-testing research, correlated in many instances with actual service experience, from the viewpoints of hardness, structure, and chemical composition. Variations in the structure and wear of automotive cylinder castings are illustrated along with the tendency of different type cast irons toward scuffing and scoring, and the cause or reasoning for such tendencies, from the standpoint of the nature of the metal structure, is pointed out.
Technical Paper
1939-01-01
J. F. Winchester, J. J. Powelson
Technical Paper
1939-01-01
Sidney J. Williams
Technical Paper
1939-01-01
A. O. Willey
Technical Paper
1939-01-01
F. L. Miller
Technical Paper
1939-01-01
Alexander v. Philippovich
Technical Paper
1939-01-01
T. R. STENBERG, C. N. MENZ
Technical Paper
1939-01-01
Lawrence J. Grunder
Magazine
1938-11-01
Magazine
1938-06-01
Magazine
1938-02-01
Technical Paper
1938-01-01
A. Lewis MacClain, Richard S. Buck
A TORQUE indicator, in which the reaction forces of the fixed gear in the propeller reduction gearing are measured, has been developed and flight-tested by Pratt & Whitney Aircraft Division of United Aircraft Corp. In this device the reaction forces are balanced by two hydraulic pistons, thus producing an oil pressure under these pistons which is proportional to the engine torque. The pressure of the oil, measured by an ordinary pressure gage in the cockpit, in conjunction with the engine speed and a suitable factor, gives the actual brake horsepower developed by the engine under all operating conditions of positive torque. Using a constant-speed propeller, it has been possible to make complete engine calibrations of power versus manifold pressures at various engine speeds at several altitudes between sea level and 20,000 ft. Fuel consumptions, induction-system temperatures and pressures at several points from the carbureter inlet to the intake port, cylinder temperatures, airplane speeds, miles per gallon, and other data were obtained in flight.
Technical Paper
1938-01-01
C. F. Prutton, A. O. Willey
IN the work reported in this paper the performance of several recognized commercial types of hypoid lubricants has been studied and a comparison made of a number of test methods including: film-strength machine tests; various types of continuous-load tests; laboratory shock tests; and road shock tests. This work has been in progress for more than fifteen months, has involved more than 50 lubricants, and more than 150 individual gear tests, each test requiring the use of a new set of gears. The results of these tests indicate deficiencies in some of the lubricants under certain of the extreme conditions employed. Of the commercial lubricants studied, those that passed the laboratory shock test lubricate hypoids quite satisfactorily under practically all other test conditions where normal temperatures were used. The performance of the lubricants in the gear tests seems to bear but a slight relation to film-strength data as obtained on laboratory test machines.
Technical Paper
1938-01-01
T. A. Boyd
THIS paper deals with the road-test portion of the extensive efforts made during 1937 by the Cooperative Fuel Research Committee to get as precise a correlation as possible between the laboratory knock ratings of automobile fuels and their corresponding ratings in cars on the road. It is anticipated that the comprehensive results of car tests reported here, taken together with the results of the laboratory rating program reported in the companion paper, will serve as the basis of the continuing studies aimed at developing the best possible correlation between road and laboratory knock ratings. Work similar to that reported here has been conducted concurrently in England by the Institution of Petroleum Technologists, using British cars and fuels. An exchange of information between the British and American groups working on this problem is being made. This commendable cooperation is indicative of the wide scope of these studies, and it is to be hoped that, as an outgrowth of this extensive cooperation, a solution will be found for the problem of making the laboratory ratings of motor fuels agree with ratings in cars which will be so satisfactory as to be universally acceptable.
Technical Paper
1938-01-01
H. O. Mathews
Technical Paper
1938-01-01
W. J. Cumming
Technical Paper
1938-01-01
Macy O. Teetor
THE elimination of wear of piston-rings and cylinders can be the ultimate goal toward which to strive but, in reaching this Utopia if it can be reached, the most practical road seems to be by way of wear reduction. Many factors indicate the necessity for a “wear-in” period. At some point in service wear-in ceases and “wear-out” starts. As wear-in takes place, performance only improves to a certain point and, from there on, piston-rings and cylinders can be considered as wearing out. The rubbing action of a piston-ring on a cylinder wall breaks particles loose from the surfaces that act as an abrasive. This breakdown of the rubbing surfaces, regenerative because of the abrasive action of the resulting loose material, causes wear. The ease with which the surface of a material will break down and the physical characteristics of the loose particles so produced are indicated to a great extent by structure. The structure of a material is therefore an indication of expected wear.
Technical Paper
1938-01-01
Howard M. Wiles
Technical Paper
1938-01-01
E. S. Twining
Technical Paper
1938-01-01
L. L. Fawcett
Technical Paper
1938-01-01
Ernest Abbott
Viewing 22231 to 22260 of 22505

Filter

  • Book
    43
  • Collection
    5
  • Magazine
    432
  • Technical Paper
    15240
  • Subscription
    1
  • Standard
    6784
  • Article
    0