1. The construction should be in strict accordance with  the technical requirements of the drawing, and the sealing work should be done according to the specific conditions on site.
2. When the four corners at the bend of furnace lower part are seal welded with steel plates, it should be noted that the steel plates must be welded with the fins on tube panel.
3. When the furnace corners are welded and sealed with the flat steels, it should be noted that the flat steel should be welded with the fins on tube panels. Besides, remove the welding slag and polish them. When the upper part and lower part of flat steel are jointed, it should not be staggered.
4. After all the sealing components of boiler pressure parts are welded, the hydrostatic test can be carried out.
5. The welding of the sealing components on the hearth must be in compliance with the drawings, so the used welding bars should be matching to the sealing components on material.