25号铸钢给水管道阀门(P=120～130大气压、T=130～140℃)的阀体,因铸造缺陷,出现一条长150毫米的裂纹。一直延伸至靠外壁圆周1/5的宽度上,裂纹最深处达0.5毫米,影响机组的安全运行。对此采取就地焊补,取得了良好的效果。焊前准备 1.在裂纹两端用φ5～8毫米的电钻打孔,并沿裂纹部位用凿子铲成U型坡口,因阀体铸件夹砂,故坡口铲的较宽,最宽处达43毫米。 Valve body on the 25th cast steel feed pipe valve (P = 120-130 atmospheres, T = 130-140 ° C) showed a crack of 150 mm in length due to casting defects. It extends to a width of 1/5 of the circumference of the outer wall, reaching a depth of 0.5 mm in the deepest crack, affecting the safe operation of the unit. To this on-site welding, and achieved good results. Welding Preparation 1. At both ends of the crack with φ5 ~ 8 mm drill drilled, and along the crack site with a chisel into a U-shaped groove, because the valve body sand casting, so the wide and wide bevel shovel Up to 43 mm.