The Wright Whirlwind-Engine Production Methods 270062
REMARKABLE performance of the Wright Whirlwind J-5 engine in the transatlantic and transpacific flights of Lindbergh, Chamberlin, Byrd, Maitland, Smith, Goebel, Jensen and Brock in the summer just closed makes this paper of great timely interest. Methods of manufacture and testing that result in a degree of perfection which enables an engine to function continuously at high speed at almost full load for 40 hr. without the failure of a single part even momentarily must be of prime importance to all internal-combustion-engine production-engineers who hold reliability as an ideal.
Extraordinary vigilance at every stage of production of every part is revealed by a reading of the paper to be the major factor contributing to success of the engine. Repeated tests and inspections are made of parts in process and of the engine after it is assembled. Test pieces formed integrally with castings and forgings are tested for their physical properties before and after heat-treating; crankcases, cylinders and tubes are tested by pneumatic pressure and pistons by hydraulic pressure, and parts are examined for defects after acid baths with the aid of magnifying glasses. Machining operations are performed to close limits and the work is inspected with gages and other precision instruments.
Operations on the various parts are described and the kinds of machine on which they are performed are specified. Jigs and fixtures are employed extensively for holding the work. While most of the operations are common practice, a few unusual methods are followed. About 85 machinery operations are required to complete a crankshaft, and even more to make a master connecting-rod.
Despite the many operations, tests and inspections, progressive machining and assembling methods are followed, and multiple drilling and other means are used for economical production. In brief, the procedure exemplifies the application to quantity machine production of the thorough care associated with individual master-mechanic handwork.