Used Reflow Ovens For Sale

SMT Sales Group specializes in the sale and delivery of highest quality used reflow ovens for SMT and PCBA use. We have vast experience with all of the top manufacturers including BTU and Heller.

Multiple zone reflow ovens are a crucial component in the manufacturing of printed circuit boards (PCBs), ensuring precise and controlled soldering of surface-mounted components. These ovens are designed with several heating zones, each serving a specific function in the reflow soldering process.

A typical multiple zone reflow oven consists of a conveyor system that moves PCBs through a sequence of temperature-controlled zones. These zones are generally divided into four main stages: preheat, soak, reflow, and cooling. Each stage plays a critical role in achieving a reliable and consistent solder joint.

The preheat zone is the first stage, where the temperature of the PCB and its components is gradually increased. This step helps to activate flux within the solder paste and prevents thermal shock, which could damage sensitive electronic components. The rate of temperature increase in this zone is carefully controlled, typically around 1-3°C per second, to ensure uniform heating.

Following preheating, the PCB enters the soak zone, where the temperature is maintained at a steady level, usually between 150°C and 180°C. This allows for the stabilization of thermal distribution across the board, ensuring that all components and solder paste reach a uniform temperature. It also facilitates the complete activation of flux, removing oxides and improving wetting performance.

The reflow zone is the most critical part of the process. In this zone, the temperature reaches its peak, usually between 230°C and 250°C, depending on the solder paste used. This causes the solder to melt and form strong metallurgical bonds between component leads and PCB pads. Modern reflow ovens use forced convection, infrared heating, or a combination of both to achieve consistent temperature distribution and prevent overheating of sensitive components.

Finally, the cooling zone ensures that the solder solidifies in a controlled manner, preventing defects such as cold joints or excessive stress on the PCB. The cooling rate is carefully managed to avoid thermal shock, which could lead to component failure or warping of the board.

Multiple zone reflow ovens provide manufacturers with flexibility and precise control over the reflow process. By adjusting the temperature profiles of each zone, they can accommodate various PCB designs, component densities, and solder paste formulations. Advanced models also include features such as nitrogen environments for oxidation prevention and real-time monitoring systems for process optimization.

Overall, multiple zone reflow ovens are essential for high-quality PCB assembly, ensuring repeatable, defect-free soldering results in modern electronics manufacturing.