Here is a brief introduction to the main equipment in a Through-Hole Technology (THT) assembly line. The core process involves inserting component leads into pre-drilled holes on a PCB, with subsequent soldering and finishing steps.

🚀 Modern THT Line Trends

While THT is a mature technology, modern lines have seen these key developments:

• Hybrid Lines with SMT: THT is often combined with Surface Mount Technology (SMT) on the same line for flexibility, especially for high-reliability products. Some modern chip mounters are designed to support both SMT and THT production scenarios.

• Automation & Integration: The use of automated material transfer systems is key to improving production rates and reducing manual handling. Equipment from different stations is integrated into a continuous flow line.

💡 How to Design for Automated THT Assembly

To ensure efficient operation of automated insertion machines, PCB design must follow specific rules:

• Board Specifications: Standard thickness is typically around 1.6mm, with strict limits on length, width, and warpage.

• Component Layout: Components cannot be placed at angles; they must be aligned with the machine's X or Y axis. A keep-out zone (usually 5mm) from the board edges and around tooling holes is required.

• Hole & Pad Design: Hole diameters must match component lead diameters with specific tolerances. Pad shapes (e.g., teardrop) differ for axial (leads bent outward) and radial (leads bent inward) components.