Brazing Metering Plates and Wear Pads
Within the aerospace industry, it has become much more economical to repair costly HPT engine components than to replace them. Cost-effective repair processes such as brazing metering plates to the dovetail of an inconel turbine blade and brazing wear pads to the midspan spar can be accomplished with quick, clean induction heating in a high vacuum brazing system.
Brazing Metering Plates
Nickel metering plates can be brazed with nickel to the dovetail section of an inconel turbine blade under high vacuum. IA application engineers have developed a successful procedure for this process using an eight-minute cycle time and brazing temperature of 2050°F. As shown at right, an optical pyrometer was used to monitor temperature and a gas quench placed above the rectangular-shaped induction heating coil to cool the part and reduce cycle time.
Brazing Wear Pads
The same type of high vacuum induction heating system can also be used to braze tungsten carbide wear pads to the midspan spar of stage one compressor blades. As shown in our Applications Lab video (PLAY VIDEO), the system can accommodate five blades at once on a rotating turntable and braze two joints per blade with a specially designed induction coil. Overall cycle time is just twenty minutes. With an IA turnkey induction heating system, the heating zone can be precisely targeted to cover very small areas.
High Vacuum Induction Heating Systems
Designed for continuous 24-hour operation right on your manufacturing floor, our high vacuum systems are ideal for processes which require stringent vacuum (<5x10[-5] torr) and/or high temperature (up to 2200°F).
The chamber is mounted on a frame that houses all the required equipment for vacuum, atmospheric and system control, as well as the induction heating station. Real time monitoring and SPC are a snap with the RS232/485 interface, optional chart recorder and optical pyrometer; process conditions can be recorded and stored for each part.
The main control unit is an industry-standard PLC. An optional web server provides full monitoring and control through a standard web browser. Parts are heated in a fully enclosed, stainless steel chamber with a controlled, inert atmosphere. Quartz viewports provide access for infrared temperature sensing. For automatic loading and unloading, a gate valve and linear sled can be added to the system.