| 摘要 |
<p>At a method for the fabrication of a glass body with an inner cavity, that is connected to the surroundings via an opening, a plaster of Paris negative (11) is made, the shape of which corresponds to the cavity of the ready glass body, of gypsum and provided with a hose (9) made of an air permeable material that from the outside extends into the plaster of Paris negative in a part thereof, that essentially corresponds to the opening of the ready glass body. The plaster of Paris negative (11) is placed in an outer mould (12), the inner shape of which corresponds to the outer shape of the ready glass body. Thereafter melt glass is fed to the outer mould. During the pouring of the glass melt suction is achieved in the plaster of Paris negative by means of the hose (9). When the glass melt has solidified around the plaster of Paris negative (11) this is dissolved and removed. At a method for fabrication of a plaster of Paris negative (11) for use at the fabrication of a glass body the plaster of Paris negative is cast in a mould, and a hose (9) made of an air permeable material is inserted into the mould before the casting. The mould is filled with plaster of Paris compound, that is brought to solidify around the hose.</p> |
