Most of the mechanical damage to pans occurs during stacking, as the bottom pan supports the entire stack’s weight. Bakeries need to maintain slow drop speeds of stacks onto conveyors. Also, plants need to minimize the drop height and angle when stacking pans and must ensure that magnetic pickup on unstackers do not apply force to the pan.
Damage can also take place at transfer points. Companies should avoid pan stacker transfers over uneven surfaces. Pan truck rollers or roller conveyors should have small diameters that are closely spaced to help distribute the load. Pan stack heights also should be as low as practical for the bakery, Mr. Tingley suggested.
Pan stops also may lead to pan damage; thus, plants must avoid excessive stop pressure and steel-on-steel contact. Any conveyors under stopped pans should be polymer to avoid abrasion on pan bottoms, he added.
Depanning should involve as little friction as possible, and steep depanning can cause resistance that will abrade release coatings. Depanners need to lift at the same rate as the conveyor to avoid further damage to pans and use as little air as possible because residual seeds, crumbs and cornmeal can blast away coatings.
Although all residuals should be cleaned from pans before storage, bakeries also must refrain from using stiff-bristle brushes that can cause abrasions to coatings, and mechanical pan indexers must be inspected to make sure they are not scratching the coating surface.
Thermal breakdown is a primary cause of release coating failures. Accordingly, bakers should avoid leaving pans in ovens during line shutdowns or running empty pans through the oven.
When pans get damaged, a bakery most likely is going to have them straightened when they have them reglazed. Straightening pans protects the new coating and helps to prevent line jams. In addition, Mr. Tingley recommended that bakeries eliminate causes of any pan damage before sending their pans off to be straightened.