| 摘要 |
PURPOSE:To reduce the fraction defective of a circular lamp and improve its quality by mixing SO2 in combustion gas at heating and deformation. CONSTITUTION:When a circular fluorescent lamp is obtained by heating and softening a straight-tube-type sealing tube made of soda glass or low lead glass and deforming it annularly, SO2 is mixed, by 30-200cc/11,000Kcal/Nm<3>, in a heating furnace heated to approximately 450 deg.C for the purpose of heating and softening process or in the heating gas in a burner for heating a sealing tube hooking pawl and the Na2SO4 coat, i.e. an SO2 formation product is produced on the surface layers of a sealing tube to be processed and a hooking pawl. When SO2 is mixed, it is recommended that an SO2 nozzle is opened in the gas flow direction at the center of piping at the specific position of a combustion gas supply tube. As a result, the generation of a crack is decreased sharply. |
