Search Results

AMONG the difficulties usually associated with measurement of combustion-chamber volume by liquid methods are amount of time required, contamination of combustion-chamber deposits, and inaccuracies arising from entrapped air. Use of a gaseous fluid such as air as the measuring medium eliminates most of the objectionable features of volume measurement with liquids. Techniques utilizing air for volume measurement fall into two basic classifications: dynamic or sonic methods, and static or pneumatic systems. Cylinder leakage and acoustic damping by engine deposits affect the accuracy of volume measurements based on dynamic properties of combustion-chamber volume, hence small volumes occupied by combustion-chamber carbon deposits must be measured separately by static or pneumatic means.

IN THE first part of this paper dealing with the metallurgical aspects of the camshaft-tappet problems met with in the design of the new Ford overhead-valve V8 engines, Messrs. Laird and Stevens describe the events which led to the adoption of the as-cast alloy-iron camshaft, nitro-carburized martensitic tappet combination. The combination cited works well in the engines described, but it is not implied that it will perform satisfactorily elsewhere. In the second portion of the paper, Mr. Iles discusses the test schedule devised in connection with the development of the camshaft-tappet materials in the new engines. It is stated that important findings will occur when such tests involve a large number of parts, making possible the study of results on a frequency basis. Tests have shown that a predominantly martensitic tappet structure results in superior performance in combination with the as-cast alloy-iron camshaft used.

A DESCRIPTION of ride analysis by experimental and mathematical methods is presented. Test facilities and instrumentation employed in experimental analysis are described, followed by presentation of actual test results. The application of electronic analog computers o t mathematical analysis is explained, and experimental results are correlated with mathematical analysis. Results of experimental and mathematical analyses are interpreted in terms of passenger comfort limits. The authors cite the need for more extensive information regarding response of the human body to motion in passenger cars.

THIS paper reports on progress to date in the development of high-temperature alloys for automotive gas turbines. Strict limitations have been set on the alloying elements in order to keep costs down — the cost factor being the main reason for this alloy search. The materials discussed here, which meet the alloy limitations and the temperature and stress requirements, fall into three classes: 1. Iron-base chromium - manganese - nitrogen austenitic alloys. 2. Iron-aluminum ferritic alloys. 3. Cast ferritic alloys with up to 12% chromium and some titanium, vanadium, molybdenum, and tungsten.

TWENTY-FIVE-YEAR statistics, detailed in this paper, show declining accident and fatality rates despite radical increase in vehicle registrations and annual vehicle miles. The author shows how the passenger-car industry has built safety into vehicles to the point where-as an example-only 14% of accidents on the Pennsylvania Turnpike over its 13-year history were attributed to vehicle failures. Paralleling these efforts and the increasing emphasis on safer highways, better traffic management and driver education, are extensive studies aimed at bypassing the human factor and increasing human safety in automotive vehicles. Among those described here are crash investigations, laboratory tests of safety devices, and establishment through various other means of design criteria for human impact tolerance.

This paper presents one writer’s viewpoint on some of the many tractor design considerations that must be recognized when incorporating one of the following types of hitches: Front and rear integral hitch, towed implement hitch, and rear integral hitch.

ONE plastic model is worth 40 lb of blueprints and 40 hr of the explaining that goes along with the prints, according to engineers who have worked with the new plastic “toys” which can serve as perfectly scaled miniatures for virtually every phase of automobile design and manufacture. The extensive benefits occasioned by this revolution in methods may be summarized thus: 1. Shortens design development time by providing a third-dimension evolvement of structure and form. 2. Used in advance discussions for compromising engineering and manufacturing problems, showing construction so clearly that troublesome problems are foreseen; thus enabling clear-cut, reliable decisions with a minimized chance of encountering major revisions. 3. Show in one minute what could not be found on prints for hours, saving time over any other methods, while generating valuable counterproposals reducing costs, operations, man-hours, and so forth. 4.

THE study of engine life, carried out by investigating engine wear in typical service, and by then striving to find the most effective ways of controlling it, forms the basis of this paper on contaminants in lubricants. The investigation involved a study of engine wear in 20,000 miles of operation typical of the average driver. The average driver was selected by using test cars from an employee transportation car pool. At the conclusion of the tests it was found that the use of the full-flow oil filter proved to be the best method for restricting engine wear caused by contaminants that get inside the engine. It was also shown that after successfully eliminating large, solid particles, further restriction of engine wear would depend upon the ability of the oil to lubricate, and upon the engine design to provide the oil supply in a manner suitable for lubrication of each part of the engine.

NODULAR cast iron, so called because the graphite is present as finely dispersed, well-rounded particles, is made in two stages: The first stage consists of the addition of magnesium or other carbide formers, which promote the formation of white iron in one normally solidifying gray. In the second stage a ferrosilicon type of inoculant overcomes the tendency toward white iron and causes the graphite to precipitate out in the form of small spherulites. The methods of making nodular iron, the effect of composition on physical properties, economic factors involved, and potential applications are discussed in this paper.

PROPER protection of metal parts operating as bearing surfaces, or in contact under relatively heavy loads, during the break-in period often means the difference between successful operation and failure. Various surface coatings have been investigated to discover which ones will give this protection. The authors discuss here three types of surface treatment for cast-iron and steel that do give superior wear and scuff resistance.