The device for removing inserts from injection moulds comprises a fixing sleeve (1) to which a insert (2) is fixed; a shaft (3) on which the fixing sleeve (1) is removably placed; at least one retaining element (12) which retains the fixing sleeve (1) on the shaft (3) in a retained position; a thrust sleeve (13), which is movable relative to said shaft (3), between a retention position of the fixing sleeve (1) and a releasing position of the fixing sleeve (1); and a stem (4) provided with an air inlet (5), said shaft (3) and said thrust sleeve (13) being movable relative to said stem (4) by injecting air through said air inlet (5).

It allows a mould insert to be removed and replaced quickly along the parting line of the mould, without leaving any marks on the plastic part.

A mould tool (100) is provided which has a multipart mould layer assembly (200; 300; 400; 500; 600) which may either be formed from a carrier (202; 302; 402; 502) and an insert (206; 306; 406; 506) defining a mould profile, or a mould face component (602; 702) having a plurality of stackable blocks (630, 632, 634) which can be assembled to form a mould layer.