本文讨论了佛罗里达州科科市如何使用水平定向钻（HDD）机进行2英寸镀锌主更换计划。本文介绍了HDD是一种非开挖技术，它使用的设备和程序旨在尽量减少表面损坏、修复要求和车辆交通中断，而对其他现有线路或服务的中断很少或没有中断。列出并讨论了各个组件，以及使用HDD技术的主要好处。

This paper discusses how the City of Cocoa, Florida used a horizontal directional drilling (HDD) machine for a 2 inch galvanized main replacement program. The paper describes how HDD is a form of trenchless technology that uses equipment and procedures intended to minimize surface damage, restoration requirements, and disruption of vehicular traffic with little or no interruption of other existing lines or services. Individual components are listed and discussed, along with the major benefits of using HDD technology.