106 results about "Thermal creep" patented technology

One embodiment of the present invention is an improved sheet glass forming apparatus. In another embodiment, a precise thermal control system redistributes the flow of molten glass at the weirs to counteract the degradation of the sheet forming apparatus which inevitably occurs during manufacturing. In yet another embodiment, the invention introduces a counteracting force to the stresses on the trough in a manner such that the thermal creep which inevitably occurs has a minimum impact on the glass flow characteristics of the forming trough. Another embodiment creates a variable external cross-section which provides hydraulic stresses that are in opposition to the surface tension and body force stresses and thus, reduces the influence of surface tension and body forces. In an alternative embodiment, the glass is preferentially cooled across its width to create forming stresses during solidification, which ensures that the glass sheet drawn is inherently flat. In an additional embodiment, the internal pressure is adjusted in each of the major components of the forming apparatus such that the pressure difference across any leakage path to the forming zone is essentially zero. Therefore, air leakage in the apparatus is minimized even though the cracks and openings exist during initial operation and develop during manufacturing.

A hollow turbine engine component with complex internal features can include a first region and a second, high resolution region. The first region can be defined by a first ceramic core piece formed by any conventional process, such as by injection molding or transfer molding. The second region can be defined by a second ceramic core piece formed separately by a method effective to produce high resolution features, such as tomo lithographic molding. The first core piece and the second core piece can be joined by interlocking engagement that once subjected to an intermediate thermal heat treatment process thermally deform to form a three dimensional interlocking joint between the first and second core pieces by allowing thermal creep to irreversibly interlock the first and second core pieces together such that the joint becomes physically locked together providing joint stability through thermal processing.