1.Inform the persons related with boiler to warm up the pipe, slowly open the by-pass valve for steam cut-off, gradually increase the pressure of main steam pipe to 0.2-0.3MPa, warm up the pipe for 20 to 30 minutes, the temperature rise shall not be larger than 5℃/min. Gradually open the steam cut-off valve and increase the pressure at 0.1-0.15Mpa /m to normal operating pressure. During pipe warming-up, gradually turn down the water draining valve according to the steam temperature.

2.After the main steam pressure rises to normal pressure, gradually open the cut-off valve fully and close the by-pass valve,