AERCO Intl., Inc., is a manufacturer of commercial water heaters and boiler systems. One of its products, a self-descaling water heater, uses vertical stacks of helical coils coupled with common steam riser and condensate return pipes. Because each independent coil set connects to the common pipe via a threaded nut connection, the integrity of these connections determines the life span of the heat exchanger. In other words, one bad fastener or loose connection can nix the whole thing.
In designing or choosing the best bolts for the job, AERCO's engineers use BoltFAST bolted joint analysis software from Sensor Products LLC. The software combines a database of fastener and interface materials with their physical characteristics; it can determine how much stress the threads can handle, how much embedding will occur when the bolt is fastened, and how much torque to apply.
BoltFAST lets the company's engineers choose the best materials for their fasteners, confirm the upper and lower torque values and capabilities of each connection, and quantify how braze in the connector threads affects the joint assembly under torque.
According to Scott McGrath, a continuous improvement engineer with AERCO, using the software has improved operations beyond the QC and design areas. Using BoltFAST has led to improvements in brazing and assembly operations and has influenced materials storage, lubricant sourcing, testing, and inspections.