本文件的目的是证明UHX部分规则的合理性，并为其提供技术标准 ASME第八节第1部分，2010年版，专门介绍U形管、固定式和浮动式的设计 封头管板换热器。确认和记录UHX规则的依据是 对于SG-HTE成员来说非常重要，以供将来参考和发展，或者如果需要其他信息 需要确认或比较。这将是早期职业工程师的宝贵参考 正在使用UHX规则或将来参与此类规则的代码开发。

The purpose of this document is to justify and provide technical criteria for the rules of Part UHX of ASME Section VIII Division 1, 2010 Edition, devoted to the design of U-tube, Fixed and Floating head Tubesheet Heat Exchangers. Confirmation and documentation of the basis for UHX-rules is important for the SG-HTE members for future reference and developments or if additional confirmation or comparisons are required. It will be a valuable reference for early career engineers that are using the UHX rules or becoming involved in Code developments of such rules in the future.