| Popis: |
Since the oil crisis, the development of energy substitutes for oil has been increasingly active in Japan. Recently, the transformation of oil-fired boilers to coal-fired boilers is increasingly planned in steam power station. Similarly, because of the rise in oil prices, there are attempts to improve the thermal efficiences of boilers for the purpose of energy saving. Moreover, projects for developing ultra super critical pressure boilers to operate under higher temperature and pressure conditions are presently going on, the world over. Concurrently, requirements for the steel boiler tubes, themselves, are becoming increasingly severe. In particular demand are steel tubes that demonstrate excellent strength at high temperature and resistance to hot corrosion; so far there has been developed no completely satisfactory steel for these tubes despite efforts in many laboratories. |
