Commercial aerospace programs are enjoying a sort of once-in-a-generation moment of growth, as established airlines replace aging fleets with newer, more energy- and emissions-efficent jets, and newer carriers are emerging to serve the traveling needs of Asian and Latin American populations.  Construction programs are booming, and those advantages are rippling up the supply chain.

It’s a good time to be manufacturing aircraft components, but it’s also creating new demands for those manufacturers – who find themselves required to deliver aluminum parts with new or better metallurgical or mechanical qualities.

L&L Special Furnace Co. Inc. has designed a dual-station, high-uniformity annealing operation, with two furnaces, semi-automated quench tanks, quench media coolers, and a centralized wash station for a company that manufactures aerospace fasteners and connectors. “Integrated” is becoming an important descriptor for designers of manufacturing systems, and for the manufacturers seeking new production techniques that match the work order and maintain some manageability and affordability for their business.

Annealing occurs when aluminum parts are heated, evenly, to 1,100°F/530°C and held for a predetermined amount of time. Temperature uniformity is critical, and both ambient and load temperature must maintain ±10°F throughout the cycle.

The L&L model DRQ2436 furnaces are manufactured according to the pyrometry specifications of ASM2750E.  The developer indicated the design has been surveyed and is capable of ±10°F/5.5°C at various temperatures up to 1,100°F/530°C throughout the 24×24×36-in. (W×H×D) work envelope. Other sizes are available, too.

All thermocouple reference ports along with TUS survey ports and recording devices are included.

There is a 7.5-HP fan to promote temperature uniformity, as well as a reinforced baffle system with adjustable louvers to direct air flow. Three-zone SCR power control and a variable drive speed control for the fans guarantee high uniformity.

The parts are placed in several 12×12×8-in. baskets and loaded into the furnace on a roller loading tray. Then, the parts are run through the annealing cycle. A stack light and signal at the end of the cycle indicate the parts are finished.

Next, the parts are transferred manually to the quenching station, and automatically quenched within 20 seconds of the door opening.

After the quench cycle is completed, a spherical roller table transfers the annealed parts to a wash station located between the two furnaces. From there, they are raised and lowered into the wash tank by a series of pneumatic cylinders.

Each furnace has its own operator station, with multiple process models available to program different cycles. The HMI gives the operator access to all of the interface components necessary to run the furnace. The power panel is centralized to help save space.

The DRQ2436 is recommended for high-throughput operations, but also smaller manufacturers processing aluminum parts to very specific aerospace regulations, as required. L&L Special Furnace noted that optional control and recorder configurations are available, and start-up service is provided for North American installations (international startup and training service available by factory quote.)