Sandwich Screens are designed to keep the mesh-free from obstruction from materials by applying gentle vibration against the bottom of the screen with a combination of either Nylon Sliders and/or Rubber Balls. These components gently rotate around the screen to provide even coverage for the entire screen. The sandwich screens are an easier solution to manage than clean ring assemblies and ball trays as the de-blinding sliders and balls are contained between both layers of mesh. This allows for faster screen changeout for cleaning or production run changes.
Epoxy-bonded mesh sandwich screens can be returned and re-screened often many times before the sliders and balls and support mesh needs to be replaced, which is significantly less costly than purchasing new screens.
Note that for 48” screens, your determination on whether or not a center hole or spacer is needed should be based on the material load on the screen. If excessive weight will be present on the screen, the top mesh may deflect and “pinch’ the sliders and balls which will severely limit their effectiveness and result in premature screen wear. The only downside to having a center spacer or center spacer with a hole is a reduction in the screening surface area.