This paper briefly introduces the requirements of PTA technology on expander and centrifugal compressor units and especially states the application of centripetal expander in three units.

Analysis shows that, under the same working condition, the impellent required in the casing expension with single-stage expansion body is less than that with multistage expa.

For the stress analysis of large-scale utility boiler pipeline, expansion center must be adopted.

The paper reports on an improvement of the elaborated model, for calculating expansion centers and taking the NG 410/9.

According to imported CE technogy, the sealing design of boiler depends on the proper location of boiler expansion center and reliable stress analysis, and the reliable mode of sealing design is thus spelt out for large capacity boilers while criteria were proposed for selection of material through analysis of insulation construction of wall and properties of material used.

The computing model of backward inflation based on mathematical morphology and several optimized computing characteristics of the model are proposed.