Method of manufacturing a grill-type support comprising two different materials and capable of being initially rigid, while allowing differential thermal expansions after installation

The method of making a supporting grid for tubes of the type in which a plurality of such grids are assembled interiorly of a tubular housing to form a steam generator, heat exchanger and the like, said method comprising the steps of;

• assembling a plurality of strips, in crossing relationship to each other, and connecting a peripheral frame thereto in which the strips are constructed of material having determined thermal expansion characteristics and the frame is constructed of a material having different thermal expansion characteristics;
• constructing the connecting portions of the strips and frame to enable relative movement therebetween when subjected to heat during use, and rigidly securing the strips and frame together to prevent relative movement therebetween during assembly, transport, installation in a housing and insertion of tubes to be supported, said step of constructing the connecting portions for rigidly securing the strips and frame together including the application of adhering material effective to rigidly interconnect the strips and frame when subjected to ambient conditions encountered from assembly to installation, the adhering material being rendered ineffective when subject to conditions encountered when the steam generator, heat exchanger and the like is operated.