Abstract: In allusion to the unplanned shutdown of a unit caused by tube breaks in water wall of a power plant, the cause of tube breaks is found out by macroscopic inspection, material analysis, hardness measurement,mechanical property test and metallographic inspection, and a shatterproof and wear-resistant water wall protection structure for the boiler cold ash bucket is proposed. The practical application proves that the structure effectively improves the shatterproof and wear-resisting ability of the water wall of cold ash bucket, and that the influence on the boiler body is controllable, ensuring the stable operation of the unit.