Profiling Convective Heat Transfer across Variable Weight Copper Stackups
Profiling variable weight copper stackups requires extended soak dwell and high gas velocity to equalize thermal delta across light pads and heavy ground planes.
Carrier Pallet
Structural Support
Rigid tooling plates hold thin or flexible printed circuit boards flat during the automated assembly process. Solder fixtures of this type, widely known as a carrier pallet, secure boards that cannot otherwise navigate the conveyor system of a pick-and-place machine or reflow oven. Clamp systems and vacuum cavities keep the substrate aligned and prevent warpage.
Correct positioning guarantees that the component pads match the solder deposition during screen printing. This mechanical stability keeps the surface coplanar, allowing high-speed placement heads to work without damaging delicate circuit tracks.
Thermal Management
Machined composite materials resist the heat of the reflow furnace to protect delicate components on the underside of the assembly. When a carrier pallet traverses a reflow oven, the tooling absorbs and dissipates thermal energy to prevent localized overheating. This thermal barrier prevents solder joints that were already formed from melting again during a second pass.
Material selection dictates how the fixture withstands thousands of thermal cycles without losing dimensional stability.
Mechanical Clearance
Dedicated recesses milled into the underside of the tooling plate provide space for pre-mounted double-sided components. During the conveyor transfer phase, a carrier pallet protects these pre-routed parts from physical contact with the drive belts. Solid relief pockets allow components of varying heights to sit securely without experiencing mechanical stress.