Identification of submerged parts inside dip coating tanks

Challenge Details

Within the automotive sector, a painting line is established for the finishing of auto bodies. This comprehensive line encompasses a sequence of processes, including washing, degreasing, electro dipping, phosphating, coating, and baking, among others. Integral to each phase are substantial tanks, each containing the requisite liquid for that specific step. Auto bodies are affixed to J-hooks and sequentially transported through these tanks. As they traverse, they follow a meticulously designed path resembling an inverted camel’s hump within each tank. However, due to a multitude of factors, there exists the risk of a car part or the entire auto body detaching and descending into the coating tank (refer image). The inability to visually inspect the bottom of these tanks complicates the identification process, making it challenging to ascertain the precise tank where a fall may have occurred. This not only prolongs the location process but also poses a significant risk of halting the production line. 

The challenge of auto parts or auto bodies falling into tanks has persisted for 15 years. The focus has been on prevention and retrieval of fallen parts. By analyzing conveyor behavior, interlocks, hanger positions, and eductor line pressure, the fallen part or auto body is identified, followed by tank fluid transfer or draining to address the issue. 

We are therefore seeking a solution for quick and accurate detection of auto body or auto part fallen in the coating tank.