本手册提供了技术和一般信息，以帮助设计、规范、采购、安装和理解高密度聚乙烯（HDPE）管道和管件。市政和咨询工程师应使用M55编制新HDPE管道项目的计划和规范。本手册将帮助管理人员、技术人员和工程师:了解聚乙烯的工程特性获取有关制造、测试和检验的关键信息获取PE管道液压方面的知识了解工作压力额定值和外部负载设计深入了解运输、搬运、，PE管道的存储和最佳实践确定PE管道的安装、维护和维修程序本第二版包括大量更新，包括与安装、外部负载和土壤特性有关的重大更新。 关于非开挖装置的章节已经过大修和更新，以反映当前的做法。本手册中包含了与当前PE树脂有关的更新。新增了关于地震应用、案例研究、管道数据和模型规范的新附录。

This manual provides both technical and general information to aid in the design, specification, procurement, installation, and understanding of high-density polyethylene (HDPE) pipe and fittings. Municipal and consulting engineers should use M55 in preparing plans and specifications for new HDPE pipe projects. This manual will help managers, technicians, and engineers to:Understand the engineering properties of polyethyleneGet key information on manufacturing, testing, and inspectionObtain knowledge on the hydraulics of PE pipeUnderstand working pressure ratings and external load designGain insight into transportation, handling, and storage best practices for PE pipeIdentify procedures for the installation, maintenance, and repair of PE pipeThis second edition includes extensive updates throughout with significant updates pertaining to installation, external loading, and soil characteristics. The section on trenchless installations has been overhauled and updated to reflect current practices. Updates pertaining to current PE resins have been included throughout the manual. New appendices on earthquake applications, case studies, pipe data, and model specifications have been added.