Dimple Operation In Sheet Metal

Dimpled steel products are increasingly used in a wide range of applications including wall studs framing and roofing members corrugated panels vineyard posts windows and door reinforcement and many other products.

Dimple operation in sheet metal.

Draw dies create the part shape by controlling metal flow into a cavity and over the forming punch. This plate prevents the metal from wrinkling as it flows into the cavity. The problems in volved in a sheet metal operation for the purpose of dlmpling a sheet for a fastener are two fold one to dimple the sheet without distorting the surface of the sheet and two in. Aluminum sheet is the easiest common.

The minimum distance between one dimple and another is four times the material thickness plus the inside radius of each dimple. When dimple dies are used they are coining the sheetmetal so the harder the applied pressure the more accurate the flare will be with less metal spring back. The minimum distance that a dimple should be from a bend is two times the material thickness plus the inside radius of the dimple plus the radius of the bend. The process uses a pair of rolls which are designed with rows of specially shaped teeth that deform the strip creating the dimple shapes from both sides of the plain sheet prior to the traditional cold roll forming process as shown in fig.

Eliminates the need for expensive air knife systems. Dimples prevent blanks from sticking together simplifying handling for operators and press feed robots. The welker roll dimpler minimizes blank sticking by adding rows of small dimples to sheet metal in coil fed operations.