| 摘要 |
<p>PURPOSE:To prevent the pollution of a treatment bath caused by a washing solution polluted with metal by the breakage of a pipe by arranging a liquid detecting sensor, which detects the inflow of a liquid, in a space between an inner pipe and an outer pipe or in a piping which reduces pressure in the space. CONSTITUTION:Boil washing is conducted by directly putting a liquid heating part 2 in a treatment bath to heat a washing solution. Pressure in a space between double structure quartz pipes 4A and 4B is reduced with a pressure reducing pump 13 to optimum pressure at which a pipe is not broken through a pressure controller 12. If breakage or a pinhole is produced in the outside quartz pipe 4A and the washing solution flows in the space, a laser sensor 10, for example, detects the washing solution based on the variation of quantity of light in a trap box 9 through a Y-shaped tube 7. By linking the sensor 10 with the heating part 2 and the operation of the pump 13, the heating part 2 and the pump 13 are turned off to stop washing and the pollution in the treatment bath can be prevented.</p> |
