Ecological, fast core removal
Wire helix, rinsing, ...
The molding material is mechanically removed or rinsed after the casting process. The tube / core casing which remains in the cast piece represents the subsequently needed channel.
There are several possibilities for drawing the pattern. With most applications it is already sufficient to ecologically remove the molding material with high pressure and water. It is generally possible within the cycle times given by the production process (within a few seconds).
As an alternative version there is a wire helix that is put in the tube with the molding material and is used as a later pattern drawing support. The channel is lifted by drawing after the cast.
In heavy metal casting classic core removal methods can be used.
The molding material can be disposed and recycled without any problems.