我们知道，回流焊温度曲线设定类型分为：RSS型和RTS型，但是这两种曲线的英文全称是什么呢？它们又有什么区别呢？

RSS：Ramp-Soak-Spike 升温-保温-回流

RSS型基本上适合所有类型锡膏，但不太适合水溶性锡膏，因为保温区锡破坏锡膏的活性而导致WETTING不好。RSS比较大的优势在于保证进入回流时，板上温差达到比较小值。如果板上有过大尺寸元件及连接器，以及PCB比较厚的RSS是比较好的选择。

RTS：Ramp-To-Spike 升温直接到回流，省去了保温区

RTS不仅适用于大多类型锡膏，对于水溶型锡膏是不错的选择。RTS可保证焊点明亮有光泽,因为RTS在预热过程中，能有效地保护FLUX从而得到比较好的WETTING效果。其次，RTS对老板来说比较经济，温区少的炉子同样能做出RTS但做RSS则不甚理想。同样，从工艺窗口来说，RTS比RSS要宽的多。

比较终选用RTS还是RSS，以实际生产的产品为主，采用什么样的曲线设置方式同时取决于锡膏类型。

As we know, the setting types of reflow welding temperature curve are RSS type and RTS type, but what is the full English name of these two curves? What's the difference?

RSS: ramp-soak -Spike warming - insulation - reflux

RSS type is basically suitable for all types of solder paste, but it is not suitable for water-soluble solder paste, because the tin in the insulation area destroys the activity of solder paste, leading to poor WETTING. The biggest advantage of RSS is to ensure that the temperature difference on the board reaches the minimum value when entering the reflux. If the board has oversized components and connectors, RSS with thicker PCBS is a good choice.

RTS: ramp-to-spike heating directly To reflux, eliminating insulation

RTS is not only suitable for most types of solder paste, it is a good choice for water soluble solder paste. RTS can ensure bright and shiny welding spots, because RTS can effectively protect FLUX in the process of preheating to obtain better WETTING effect. Secondly, RTS is relatively economical for the boss, and a stove with few warm areas can also make RTS, but RSS is not ideal. Also, from the perspective of process window, RTS is much wider than RSS.

The final choice of RTS or RSS is based on the actual product, and the curve setting depends on the type of solder paste.