PLASMA ARC AND THERMAL LANCE TECHNIQUES FOR CUTTING CONCRETE AND STEEL
The plasma arc technique is used today in industrial practice for any metal, but mainly for cutting stainless steel, carbon steel and aluminium. In air the maximum thickness that was cut in the performed tests was 150 mm, both with ferric and austenitic steel. Underwater the maximum thickness cut was 103 mm. The two types of torch used in the tests are those used today: the plasma shaped electrode torch (WIPC) and the pointed electrode torch (DMC-GRUN). Two different types of gas were compared: an argon - nitrogen mixture and an argon - hydrogen mixture. The second mixture adopted results in less dust emission. The production of dust and aerosols also depends on the cutting speed, on the kind of steel, but mainly on the environmental conditions; it is reduced up to 500 times under water. Dust and aerosols can jeopardize the efficiency of the system; moreover, the ambient air can have high level radiation fields. In direct and direct protections are needed (shields, remote control, robots, etc.). Tentative procedures for dismantling two types of BWR reactor are examined. Two series of tests demonstrated the feasibility of cutting the most geometrically difficult parts of the reactor internals. The thermal lance technique is used in industrial practice mainly for dismantling large reinforced concrete structures. This technique can be applied to dismantle nuclear facilities, even though it can cause some problems due to the gases, fumes and lapilli produced. In addition, the cost of this technique seems to be generally higher than the cost of other techniques.
Bibliographic Reference: EUR 10402 EN (1986) FS, 167 P., BFR 550, EUROFFICE, LUXEMBOURG, POB 1003
Availability: Can be ordered online
Record Number: 1989124093100 / Last updated on: 1987-01-01
Available languages: en