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原文
After welding cast steel valve rating Non-destructive inspection for welding defects reported regional level, JB/T3595-2002 forth, cast steel valves for power plant valves and welding parts of the groove should be GB/T5677-1985 assessed, three qualified. GB/T3323-1987 valve butt weld should be assessed, two qualified. JB/T644-2008 of casting exist in two different defect levels are also given clear that exist in the assessment area for more than two or two and a different level of defects, whichever is the lowest level as a composite rating . Exist two or more types of defects and the same level, its overall level should be lowered one level. For the welding zone of slag defects, not fused, and incomplete penetration, JB/T6440-2008 forth, can be seen as casting defects to evaluate the slag, welding defects in the pore region can be seen as casting porosity defects assessed . General condition of the valve does not mark the valve order contract casting level, fewer welding defects specified in the contract after the passing grade, which is often to the production of valves, inspection and sale brought a lot of contradictions. According to our current level of the actual quality of steel castings and many years of experience, assess the level of welding area should not be less than is generally believed that the three GB/T5677-1985 that ASMEE446b standards for grade Ⅲ. Acid corrosion of steel pipeline operating conditions and high pressure cast steel valve pressure valve casing parts, generally should reach ASMEE446b Ⅱ or above standard. Ray results showed that the standard procedures and norms welding defects in the region, deposition process generated defects, even less than the casting itself, a higher level. In short, the repair welding as part of the manufacturing process, can not be taken lightly.
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译文：
对于补焊区域无损检查缺陷报告的等级,JB/T3595-2002中规定,对于电站阀的铸钢件阀门坡口和补焊部位应按GB/T5677-1985进行评定,三级合格。阀门对接焊缝应按GB/T3323-1987进行评定,二级合格。JB/T644-2008中对铸件中同时存在二种不同等级缺陷也给出了明确规定,在评定区同时存在两类或两类以上且等级不同的缺陷时,取其中最低等级定为综合评定等级。同时存在两类或两类以上且等级相同的缺陷时,其综合等级应降低一级。对于补焊区缺陷的夹渣、未溶合和未焊透,JB/T6440-2008中规定,可看作铸造缺陷的夹渣来评定,补焊区缺陷的气孔可看作铸造缺陷的气孔评定。一般工况阀门的订货合同中不标注阀门铸件等级,更少在合同中注明缺陷补焊后的合格等级,这往往给阀门的生产、检验和销售带来诸多矛盾。根据我国目前铸钢件的实际质量水平和多年经验,补焊区域评定的等级一般认为不应低于GB/T5677-1985中的三级,即ASMEE446b标准规定的Ⅲ级。耐酸耐蚀管线工况的铸钢阀门和高压铸钢阀门的壳体承压部位,一般应达到ASMEE446bⅡ级或以上标准。射线检查结果表明,经符合标准程序和规范补焊的缺陷区域,熔敷过程中生成的缺陷,比铸件本身还要少,级别更高。总之,补焊作为制造过程的一部分,不可掉以轻心。

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