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A general analytical and test procedure approach is presented for shafts under fatigue loading conditions. Construction and interpretation of comprehensive analytical curves are outlined, comprising the basic loading conditions of torsion alone, bending alone, combined bending and torsion, and cumulative damage. General spline design curves derived from fatigue tests are presented for torsional fatigue loading. The concept of nominal stress is used in correlating test and analytical curves, introducing simplicity and perspective in interpreting such complex factors on fatigue life as stress concentration, physical properties, and mode of loading.

Scientific methodology and engineering techniques were applied to a series of three automobile rear-end collision experiments to provide data relating to seat, seat backrest, and head-restraint design. Five seat back heights and four seat back strength values were studied in connection with their practicality and relative protective features, when subjected to a 55 mph rear-end collision exposure. These research data provide a basic reference system of high-speed collision performance for seat designs with respect to occupant size and proximity to injury producing structures. Additionally, methodology, instrumentation, and related equipment required for post-crash fire studies were included in experiment 106, providing what is believed to be the first published data on the precise time-related events associated with collision-induced passenger car fires. Design revisions suggested by these findings are discussed.

A low cost data acquisition and reduction system for an engine dynamometer laboratory is described. The system uses specially prepared Port-A-Punch data cards for input to a computerized data reduction program with the dynamometer operator functioning as an analog to digital converter.

This paper describes three Allis-Chalmers' data acquisition systems showing the flexible points of each, and how the systems could be more flexible. These systems include a mobile system used for farm equipment testing, an 800 channel system used to collect test data from fuel cells, and a general purpose digital computer. Software support to process the data is also discussed.

To calculate the true exhaust gas energy of a high-pressure turbocharged diesel engine, the pressures and the instantaneous temperatures were measured in the exhaust gas pipe of a test engine. The results and the problems encountered during measuring are described, and simple approximation equations for the instantaneous temperature are compared with the measured temperatures. Energy calculations carried out with these temperature functions have shown that the deviations from the true values are only slight.

Mobile spars have proved a highly economic tool in woods production. They have affected historic concepts regarding forest engineering and road construction. Detailed logging cost analysis will continue to broaden their application and maintain their position as a “high return on investment” machine.

The 550 shp ST6 turbine engine was adapted for industrial use from the PT6 aero engine. Its performance and operating characteristics make it suited to a wide field of applications. Extensive development and test programs have been conducted on industrial features incorporated into the engine. Experience has been gained in many industrial and marine installations and some of these are dealt with in detail. The engine has shown excellent versatility and durability to date in industrial and marine use.

A self-propelled processing plant, for converting whole logs into pulp chips, is described with emphasis on the chipper power source. A comparison is made between gas turbine and diesel engines as the prime power for chipping. Application of the gas turbine engine as related to total plant design, field experience, economics, and customer acceptance is also discussed.

The paper reviews the present applications of an 1100 hp industrial gas turbine engine. It briefly discusses gas turbine designs, especially, the simple cycle version. It comments on the single and two-shaft configurations as well as other primary features of the engine. A series of photographs is included showing typical industrial applications. Some future applications are projected.

The log stacker is a high capacity lift truck used in the dry handling of logs at sawmills and reloading sites. Its work operations include handling logs on and off trucks, into and out of storage stacks, and in sorting. This paper describes the largest such vehicle now in existence: the FWD Wagner L-130 Lumber Jack. Described in detail is the hydraulic circuit which provides 475 hp with individual direction of six functions or combinations using all or part of the power available.

For industrial (nonaerospace) applications, hydraulic system pressures can be increased to the “high pressure” (2000-5000psi) or even the “very high pressure” range (5000-10,-000 psi) with fluids available currently. Fluid properties that must be considered for high pressure use are: lubricity, antiwear, bulk modulus, cleanliness, vaporization temperature, stability, and seal compatibility. For fire resistance, extreme low temperature and extreme high temperature synthetics are required. High quality, petroleum-base fluids have the greatest number of relative advantages for regular high pressure hydraulic service. Principal among these advantages are: lubricity, antiwear, cost, availability, ease of sealing, and stability. New synthetic fluids are available with unique properties for special applications. Costs relative to petroleum oils range from 5:1 up to over 1000:1.

The on-off highway truck must serve two primary purposes. It must be capable of going into adverse terrain to pick up a load and be able to bring the load out to improved private roads or public highways. It must then have relatively high speed highway capabilities in order to keep round trip time to a minimum. This paper discusses the transmission requirements for this truck and presents a case for selecting a mechanical transmission to serve these purposes.

Federal law mandates that all United States passenger car gasoline engines be equipped with crankcase and exhaust emission devices in 1968. These devices, combined with increased short-trip stop-and-go driving under extended oil drain periods, likely will challenge the performance properties of motor oils. Interim results from various field and laboratory tests show that motor oils are available to meet the expected needs of 1968 engines provided the oils are drained more frequently as engine mileage accumulates. The MS sequence tests were found to be reliable laboratory test tools to screen motor oils prior to field testing. As experience accumulates with 1968 engines, continued surveillance by both the automotive and petroleum industries is recommended to keep engine requirements and motor oil qualities in tune with each other.

Since emission control devices are mandatory on the 1968 automobiles nationwide, the recirculation of blow-by gases within the engine necessitates a new approach to the evaluation of engine oils. New test methods incorporating these closed ventilation systems, namely, the Falcon Rust Test and the Sequence V-B Sludge Test, are necessary for predicting motor oil performance. Closed ventilation systems increase the load on the motor oil, and complicate the lubrication mechanism because these highly acidic blow-by gases are recycled. In the West Coast area, where both open and closed systems were first used, performance of many branded motor oils deteriorated; others were unaffected. Examples of corrosive engine wear were observed where improper motor oils were used. It is the intent of this paper to provide a portion of the technical record of meeting this challenge, and to point out important oil test parameters and additive combinations effective in meeting these new problems.

An interdivisional organization has been formed within General Motors to supply special information to assist in the development of friction materials. People with special talents from nine different divisions of the corporation have been active contributors in the exploration of 33 special projects by this organization, which has been called the “Beta” Group. From these projects have come new procedures, new devices, and new information which should be helpful to chassis engineers and development people who are interested in brake lining improvements.

The experimental program described here was conducted in order to determine the effect of fixed and variable steering gear ratio on driver task performance. Three fixed gearbox ratios and two variable ratios of the Bendix Varamatic type were tested, using a single vehicle. Four steady turn driving tasks were used, each producing the same lateral “g” (0.2g) and a transient maneuver task, induced by applying a step change in front wheel angle to the vehicle, was also used. The pool of test subjects consisted of student drivers with an average of 39 hr of on-the-road driving experience.

Disc brakes and modulating valves work together to improve the stability of a car during braking. This fact, as well as the increased possibility of braking control, comprise the main reasons for the tendency of European manufacturers to employ four disc brakes and modulating valves in their cars. Floating and fixed calipers are both used, but the first category has advantages which seem conclusive for the future. The next step could be the use of antiskid devices, the object of considerable research efforts, none of which has given any conclusive results to date.

An experimental-analytic method of determining the stress distribution in narrow faced spur gear teeth is presented. The successful application of photostress to this contact problem is reported. It utilizes a digital computer routine developed for separating stresses in any general two-dimensional region. Results for two pairs of gears are presented. Comparison is made with values predicted by the modified Lewis formula, the Kelley and Pedersen equation, and by the Belajef solution of the Hertz contact problem for two cylinders.

It is necessary to consider the brake lining and brake drum as a mating pair for optimum performance. Some of the characteristics of brake linings, the interrelationship of the brake drum, and their combined effect on certain aspects of brake performance are discussed. Temperature, rubbing speed, unit pressure, and mating surface material are factors affecting the coefficient of friction of the lining. Brake maintenance also affects the operation of the lining as well as the entire brake system. By understanding the various properties of linings and drums and the concept of mating pairs, certain compromises can be reached which offer optimum performance for a specific set of operating conditions.