US Patent 7765841 Quality analysis of tube bending processes including mandrel fault detection

A disclosed device and method are useful for monitoring a tube bending process. An example sensor detects a force associated with moving a mandrel in tubing during at least a portion of a tube bending process. The detected force is used to determine a quality of the tube bending process. For example, a detected pulling force provides an indication of whether a bent portion of a tube is within an acceptable range of a desired configuration. The detected pulling force is also useful to provide an indication of whether a condition of a mandrel or a machine used during the process is as expected.