PACE’s ThermoFlo TF 2700 rework station  is a very popular automated, cost effective solution for area array package rework.  Designed for today’s PCBs, this system can safely install and remove a wide variety of components such as ball grid arrays, chip scale packages, quad flat non-lead, ceramic ball grid arrays, and other surface mount devices.  
The PC based software allows the easy creation of thermal profiles and guides the operator through an intuitive interface that virtually automates the process.  All operations, component pick-up, alignment, placement, and reflow are completed in a single axis, eliminating the risk of component movement after placement.  Component pick-up is achieved by placing the component into an adjustable nest above the optics assembly.  The reflow head automatically picks up the component and moves it to the proper focal position for alignment.  A high-flow vacuum pump holds the component securely.  Flux dipping and stenciling can also be incorporated into the component pick-up procedure.  The PCB holder features a fine micrometer adjustment for the most delicate X and Y-axis alignments. Precise and accurate, within 25 μm (.001”), Z axis movement is ensured through a twin rail, linear bearing motion control assembly that is similar to those used on automated pick and place equipment.  The component is placed on the PCB with a controlled, minimum pressure.

The TF-2700 optic system utilizes advanced digital, Sony color cameras and a high quality dichroic prism for very fine image clarity.  This is achieved through Pace’s high resolution Vision Overlay System or VOS which does not require routine calibration.  The images are viewed using the PC in standard or full screen viewing modes.  The Sony camera features 72X magnification and both auto-focus and manual capability.  The automatically controlled, retractable optics housing protects the VOS from dirt and contamination that are common intrusions in some work environments.  Independent lighting controls for the ultra white, high power, LED based lighting provides maximum overlay contrast for the component and PCB.  This lighting eliminates shadow and has wide dispersion angles to adequately illuminate large components.

ThermoFlo systems combine a convective topside 1200 Watt heater with stable and powerful IR bottom-side heating.  This closed loop temperature control and unique vented nozzle design helps maintain uniform temperature distribution during reflow.  High power heaters allow for successful, safe and repeatable reflow at low temperatures.  The rework station is self-contained and does not require an external air supply or vacuum connections.

For more information related to this article, or to schedule a demonstration of the Pace ThermoFlo TF-2700 located at the EMPF, contact Ken Friedman, 610-362-1200 x 279 or via email at kfriedman@aciusa.org.