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What are the hazards if the weld bead height is too large? This article has been specially organized: (1) Causes stress concentration. Since the weld bead protrudes more than the surrounding material, this leads to stress concentration at the weld, making that area more prone to fracture or plastic deformation. (2) Increases the risk of cracks. A higher weld bead height may make the welded joint more prone to cracking, especially under prolonged exposure to external stresses. (3) Affects the fatigue strength of welded structures. The presence of weld excess height disrupts the continuity of the structure in the fusion zone and heat-affected zone of the welded joint, thereby reducing its fatigue strength. (4) Increases the risk of pores and corrosion. Excessively high weld bead heights can lead to excessively high temperatures in the areas surrounding the weld, resulting in the formation of pores; moreover, stress concentration points are more prone to corrosion. (5) Affects the service life of pressure vessels. In pressure vessels, the presence of excess height can lead to localized stress concentration, thereby reducing the service life of the equipment. (6) Increases energy losses and anti-corrosion costs. In conveyance pipelines, the excess height of the internal welds increases the frictional resistance to the conveyed medium, thereby raising energy consumption ； The excess height of the external welds requires a thicker anti-corrosion layer, thereby increasing the costs associated with corrosion protection. Someone once created two sets of test containers: in one set, the excess height on the weld was ground off so that the weld surface was level with the base material surface; this set was referred to as the group with excess height removed ； The other group, after welding, was left untreated and is referred to as the retained burr group. These two sets of containers were subjected to pressure fatigue testing under the same operating conditions in order to compare their fatigue life. The test results show that the containers in the retained height group failed first, and the average fatigue life of the two groups differed by 2.0 to 2.5 times. Therefore, during the welding process, appropriate techniques and welding parameters should be employed to reduce the formation of weld excess height, thereby enhancing the safety and service life of the welded structure. If the weld bead height exceeds the value specified in the selection criteria, grinding should be performed.