On the hydrostatic test of water-tube boilers
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The design of the heat exchanger (of a type similar to an air cooler) is carried out in accordance with GBT 16507: the steam flowing through the tubes is superheated, with a working pressure of 8.3 MPa; the designed pressure is 8.8 MPa, and the designed temperature is 380℃； Shell-side air, inlet pressure 4 kPa, temperature 160°C). The pattern indicates a hydrostatic test pressure of 12.45 MPa. Is it correct? Doesn’t it need to be considered that the allowable stress at 380°C is reduced compared to room temperature?
1.5 times the working pressure – that’s just as simple and brutal as it is.
Won’t there be problems under high-temperature conditions like this?
I don’t know what you’re worried about? Although the allowable stress of materials at 380°C is lower compared to room temperature, it is not permissible to use values above 8.8 MPa at high temperatures. Moreover, Li Zhiguang states in the \"Application Manual for Boiler Strength Calculation Standards (Revised Edition)\": \"The hydrostatic test is the final process-related test, used to check for leaks caused by poor manufacturing techniques or defects in the steel material; it is not a test to verify the strength properties of the boiler.\" ”
According to Section 9.3 of GB/T16507, the hydrostatic test pressure for components is 1.5 times their operating pressure; 8.3*1.5=12.45 MPa.