The amount of available space in the die will help determine how many springs to use and what sizes to choose. ![]() A too-high spring pressure will inhibit the drawing of the material, while too little pressure will draw material up the form and fail to provide a uniform wall thickness. It is not uncommon to find a note on a draw die design stating the spring requirement as “springs to suit.”Īs the binder ring holds the material in its locating position, the spring pressure required tends to be adjusted to eliminate the tearing and shearing that may occur while the material is being drawn or stretched. Pressure requirements for binder rings in draw dies tend to be less scientific, determined by trial and error. The pad pressure also helps to prevent material from scoring or tearing as it is being formed. The formula reads:įigure 3: This form die shows spring position and travel.Ī forming operation requires more pad pressure than a bending operation because of the need to control sheet material movement over the forms and maintain its new shape. These elements multiplied together will give you the perforating pressure. To do this, you need to know the thickness and shear strength of the part material as well as the length of shear or cutting distance. ![]() To determine spring pressure for a spring used in a stripper, first calculate the perforating pressure for the entire die. To select a die spring, you first should gather information about three different aspects of the die design: how much pressure is needed what spring size and how many are needed to produce that pressure and how far these springs must collapse or travel. ![]() The goal is to provide adequate die spring pressure within the limited remaining space of the die (see Figure 1). The springs also provide controlled return pressure for the die stripper to permit the punches and other die-mounted tools to evacuate the material during the press’s return stroke.ĭie springs are most commonly used to actuate strippers, but they can also be found behind form pressure pads and binder rings in draw dies. Figure 1: This flow chart shows the information needed to select the proper die spring.ĭie springs, an essential stamping die component, create the optimal pressure for restraining the sheet material in a fixed position while it is being pierced, formed, flanged, or trimmed.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |