本出版物包含单相流中确定R-12、R-22、R-502和R-717制冷剂管道尺寸的信息。它不打算成为应用标准。有关此类信息，请参考ASHRAE手册和产品目录。压力损失图表采用了一种新的格式，该格式易于使用，误差最小。输入输出关系遵循以灰色打印的水平直线。这样，就避免了因密集对角线上的倾斜转折点（许多以前的图表都有这种情况）而产生的误差。通过读取压力和温度损失，在吸入和排出管线损失图表中提供了额外的便利。

This publication contains information for sizing R-12, R-22, R-502and R-717 refrigerant piping in single-phase flow. It is not intended to be an application standard. The user is referred to the ASHRAE HANDBOOK &Product Directory for such information. The pressure loss charts incorporate a new format developed for ease of use with minimum chance for errors. The input-output relation follows a horizontal straight line printed in grey. Thus, errors due to oblique turning points on closely spaced diagonal lines (common to many previous charts) are avoided. Additional convenience is provided in the suction and discharge line loss charts by read-out in both pressure and temperature loss.