Patent ID: 8262977

Claim:
A process for manufacturing a shaft bottom part made of concrete and having an individual chute of a predetermined shape, wherein said process comprises the steps of: providing a plurality of prefabricated moulded pieces ( 9 , 14 ) having a linear longitudinal extension and a plurality of prefabricated moulded pieces ( 10 , 15 ) having an arc-shaped longitudinal extension; selecting two or more moulded pieces ( 9 , 10 , 14 , 15 ) out of said plurality of prefabricated moulded pieces ( 9 , 10 , 14 , 15 ); cutting and trimming the selected moulded pieces ( 9 , 10 , 14 , 15 ) to adapt the selected moulded pieces ( 9 , 10 , 14 , 15 ) to the predetermined shape of the chute, wherein cutting the selected moulded pieces ( 9 , 10 , 14 , 15 ) comprises cutting the selected moulded pieces ( 9 , 10 , 14 , 15 ) to a required length according to the predetermined shape of the chute and trimming the selected moulded pieces ( 9 , 10 , 14 , 15 ) comprises trimming the selected moulded pieces ( 9 , 10 , 14 , 15 ) in height according to the predetermined shape of the chute and/or trimming the selected moulded pieces ( 9 , 10 , 14 , 15 ) at the face side of the selected moulded pieces ( 9 , 10 , 14 , 15 ) for fitting together according to the predetermined shape of the chute; assembling the selected moulded pieces ( 9 , 10 , 14 , 15 ) for forming a moulded body ( 8 ) according to the individual chute geometry, said moulded body ( 8 , 18 ) forming the negative mould of the chute; inserting the moulded body ( 8 , 18 ) into a bottom mould ( 1 ) comprising a mould bottom ( 3 ) and a mantle ( 2 ); filling a mixture of concrete into the bottom mould ( 1 ); and removing the moulded body ( 8 , 18 ) from the shaft bottom after or simultaneously with stripping the formwork from the shaft bottom.