The most common of these classes were A, B, C and D for 100, 200, 300 and 400 feet hydraulic head, respectively. The 1908 AWWA standards employed a system of class designations applied to specific wall thicknesses in diameters 4" to 84" inclusive for a range of hydraulic heads. The second dealt with actual design of pipe based on Brackett’s method with variations. The first of these used thicknesses for pipe determined by averaging the thicknesses used in a large number of American cities. Prior to 1908, at least two unofficial documents dealing with pipe design were acknowledged by AWWA. In 1908, AWWA adopted a standard covering bell and spigot pipe produced in 12-foot laying lengths by the pit casting method. In the late 1880s, a formula by Dexter Brackett, distribution engineer for the City of Boston, was adopted by the New England Water Works Association as its standard.Īlthough the 1902 NEWWA standards did not provide a formula for pipe thicknesses, the Brackett formula was used in determining the thicknesses recommended. Kirkwood’s calculations took into consideration casting imperfection, strength of the metal and other factors affecting the life of the pipe. Kirkwood, as chief engineer for the Brooklyn Water Works, developed a design for cast iron pipe that was a variant of the Barlow formula. In the development of the design of cast iron pipe, this formula has been modified in several ways by prominent water works engineers such as Allen Hazen, Thomas H. The formula may be stated as t= PD/2S in which t is the thickness of the pipe in inches P is the internal pressure in pounds per square inch (psi) D is the outside diameter in inches and S is the allowable working stress of the metal in pounds per square inch. It embodies the basic principle for design of a cylinder for internal pressure. The basis for design in almost all specifications to date is the Barlow formula, or "Hoop Stress" formula.
#ASTM STANDARDS ABBREVIATIONS MANUAL#
After all approvals have been received, including a public review by both AWWA and ANSI, the standard, manual or revision is published and made available to the public.Ī brief review of the older specifications in chronological order may help define their usefulness, as well as help in the appreciation of the improved modern standards. After approval it is submitted to the AWWA Standards Council for approval. The subcommittee prepares and submits the document to the Standards Committee for approval. The committee’s membership is comprised of representatives from consumer groups, producer groups and general interest groups, including a number of professionals from AMERICAN.Ī standard, manual or revision is developed by a subcommittee assigned to that task.
#ASTM STANDARDS ABBREVIATIONS MANUALS#
The committee is responsible for the development of standards and manuals for ductile iron pressure pipe for water and other liquids and for fittings used with such pipe. It was reorganized under American Standards Association Procedures in 1955, and in 1984 it became a member of the AWWA committee structure. The AWWA Standards Committee A21 on Ductile and Gray Iron Pipe and Fittings was organized in 1926 under the procedures of the American Engineering Standards Committee.