穿孔回流焊（THR）是一种常见的表面贴装技术，它可以在电路板上焊接穿孔元件。穿孔元件通常具有较大的引脚直径，这使得它们难以使用传统的表面贴装技术进行焊接。穿孔回流焊（THR）技术通过在穿孔孔径中添加焊膏，然后在回流焊炉中进行加热，使焊膏熔化并与电路板焊接。穿孔回流焊（THR）技术可以提高电路板的可靠性和性能，因为它可以提供更好的焊接连接和更好的热传递。

PD IEC TR 61760-3-1:2022标准提供了使用焊膏表面印刷方法的穿孔直径设计指南。该指南旨在确保穿孔焊接的质量和可靠性。穿孔直径的设计应考虑到焊膏的流动性和穿孔引脚的直径。穿孔直径应该足够大，以确保焊膏可以流动到穿孔引脚的底部，并形成一个均匀的焊接连接。然而，穿孔直径也不能太大，否则焊膏可能会流到电路板的另一侧，导致焊接不良或短路。

此外，PD IEC TR 61760-3-1:2022标准还提供了其他有关穿孔回流焊（THR）焊接元件规范的标准方法。这些方法包括焊接温度和时间的规范，焊接质量的检测方法，以及焊接后的可靠性测试方法。这些方法可以帮助制造商确保穿孔回流焊（THR）焊接元件的质量和可靠性。

相关标准
- IEC 61760-3-1:2019 Surface mounting technology - Standard method for the specification of components for through hole reflow (THR) soldering - Part 3-1: Blank detail specification - Fixed capacitors for use in electronic equipment.
- IEC 61760-3-2:2019 Surface mounting technology - Standard method for the specification of components for through hole reflow (THR) soldering - Part 3-2: Blank detail specification - Fixed resistors for use in electronic equipment.
- IEC 61760-3-3:2019 Surface mounting technology - Standard method for the specification of components for through hole reflow (THR) soldering - Part 3-3: Blank detail specification - Fixed inductors for use in electronic equipment.
- IEC 61760-3-4:2019 Surface mounting technology - Standard method for the specification of components for through hole reflow (THR) soldering - Part 3-4: Blank detail specification - Fixed surface mount capacitors for use in electronic equipment.
- IEC 61760-3-5:2019 Surface mounting technology - Standard method for the specification of components for through hole reflow (THR) soldering - Part 3-5: Blank detail specification - Fixed surface mount resistors for use in electronic equipment.