Covering core

Sand core inserted into the mold from the outside (from above), which has the function of covering the mold cavity.

The cores referred to as covering core have a support and contact surface with a larger cross section than the actual core cross section (Fig. 1). In this way, these cores cover the mold cavity. If a hanging core is designed with this structural covering feature, it is also referred to as covering core.

Covering cores may be used instead of the mold cope. If a cope is used, they prevent movement in vertical direction. In this scenario the covering part of the core is clamped between cope and drag. This prevents the core from being lifted up during casting due to buoyancy. Covering cores may also include the gating and riser system (see also Hanging core).


  • Fig. 1: Single-piece casting mold with covering core (acc. to R. Roller)