Reflow Process Inspection is catching on as the next advancement in-line inspection systems for SMT Reflow. I have pulled together the various aspects of RPI to better explain how it works and what are its benefits.

How does RPI fit into the inspection processes in the SMT factory?

Unlike SPI and AOI that are defect inspection systems specifically designed for viewing solder deposition and component assembly respectively, RPI complements these systems by inspecting the performance of the thermal process IN-LINE. RPI inspects the thermal process for any joint, including those that are not visible to the AOI system such as BGA components.

What is being measured?

RPI charts the thermal Process Yield and DPMO

What are the RPI benefits?

RPI provides information on the “health” of the thermal process over time. The Yield and DPMO charts provide instant understanding of detrimental changes in the process. The following format is easy to read and understand and often used by management as well as engineers.