IN its discussion of the analysis and balancing of air-brake systems, this paper places particular stress on brake rigging, or the foundation brake, and its maintenance.
Most of the chronic braking troubles could be eliminated, Mr. Johnson contends, if all brakes were balanced and then subjected to a well-planned and executed periodic maintenance program. In balancing, he explains, the brakes are modified so that all the brake shoes on the vehicle are contacting the drum at the same low pressure at the same time during the brake application. Benefits of such balancing and maintenance reported by the author include increased brake lining life; and reduction of: brake-drum breakage and checking, drum scoring, grease on brake linings, brake adjustments, and bearing failures and tire blowouts caused by heat.
The remainder of the paper is devoted to details of the brake analysis and maintenance program. Various points are emphasized by charts compiled from data obtained by testing vehicles in actual service. Although the tests reported were selected at random, Mr. Johnson avers that the data hold true for operations in any part of the country.