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THIS paper describes the development and utilization of a new Ford free-piston power-plant, the model 519. Mr. Noren traces the development of the engine from the initial idea to the point where commercial utilization could be considered. Mr. Erwin describes one commercial use: in the Typhoon tractor. The ratio of size and weight to horsepower is favorable for farm tractors, being smaller and lighter than equivalent diesel engines. The performance of the tractor has been satisfactory thus far, operating smoothly and being practically vibration-free, with little noise. The advantages of the free-piston gasifier, as reported by the authors, are: flexibility, fuel economy, no need for auxiliary starting engine, economical manufacture of a wide range of engine sizes, adaptability to a wide range of fuels, and good torque characteristics.

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.

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.