本标准描述了符合ANSI/AWWA C151/A21.51《离心铸造球墨铸铁管》要求的球墨铸铁管的厚度设计。第。4.1概述了设计程序，第。4.2给出了设计示例。第。4.3解释设计基础。与使用Sec中的程序相反。4.1或秒。4.3，设计者可直接参考表12至14。表12列出了标准铺设条件和某些覆盖层深度的厚度。表13列出了150 psi-350 psi（1034 kPa-2413 kPa）水工作压力的厚度。对于给定的沟槽载荷或内部压力，应使用表12或表13中的较大厚度。 表14列出了标准铺设条件和标准压力等级的工作压力和最大覆盖深度。表15列出了球墨铸铁管的特殊厚度等级。

This standard describes the thickness design of ductile-iron pipe complying with the requirements of ANSI/AWWA C151/A21.51, Ductile-Iron Pipe, Centrifugally Cast. Sec. 4.1 outlines the design procedure, and Sec. 4.2 gives a design example. Sec. 4.3 explains the basis of design. As opposed to using procedures in Sec. 4.1 or Sec. 4.3, the designer may reference Tables 12 through 14 directly. Table 12 lists thicknesses for standard laying conditions and certain depths of cover. Table 13 lists thicknesses for 150 psi-350 psi (1,034 kPa-2,413 kPa) water working pressure. The greater thickness from Table 12 or Table 13 for given trench load or internal pressure should be used. Table 14 lists working pressures and maximum depths of cover for standard laying conditions and standard pressure classes. Table 15 lists special thickness classes of ductile-iron pipe.