不同种类供水用不锈钢管性能评估

Performance Evaluation of Different Kinds'Stainless Steel Pipes for Water Supply

以供水用不锈钢管作为研究对象,通过检测其化学成分组成、外观尺寸、力学性能和防腐蚀性能等,评估现阶段国内供水用不锈钢管的性能水平。结果表明,供水用不锈钢管均满足现阶段国家标准规定的要求。化学成分组成方面,铬(Cr)、镍(Ni)、钼(Mo)3种贵金属均偏于低值,Ni元素在S30408不锈钢管材中质量分数为8.00%~8.05%,在S31603管材中的质量分数为10.02%~10.07%;Mo元素在S31603管材中的质量分数为2.00%~2.06%。外观尺寸方面,不锈钢管的外径均为正偏差,壁厚则大多为负偏差。力学性能方面,不锈钢管的力学性能远高于标准规定的要求,在规定非比例延伸强度和抗拉强度两个指标中尤为体现。不锈钢管的防腐蚀能力优秀,即使进行了铜加速乙酸盐雾(CASS)试验仍无腐蚀现象。冰冻前后的不锈钢管在力学性能上并无明显区别,表明现阶段不锈钢管的材料强度能承受由冰冻水体体积增大而产生的压力。

The stainless steel pipes for water supply were taken as the research object,the performance evaluation was assessed by the testing of chemical composition,external dimensions,mechanical properties and corrosion resistance.The results showed that stainless steel pipes for water supply meet the requirements of current national standards.The contents of chromium(Cr),nickel(Ni)and molybdenum(Mo)in pipes were at relatively low levels.The mass fraction of Ni in S30408 stainless steel pipes were between 8.00%and 8.05%,the mass fraction of Ni in S31603 stainless steel pipes were between 10.02%and 10.07%;the mass fraction of Mo in S31603 stainless steel pipes were between 2.00%and 2.06%.The outer diameters of stainless steel pipes were positive deviations,and the wall thicknesses were negative deviations.The mechanical properties of stainless steel pipes were far higher than the requirements specified in the standard,especially for the proof strength of non-proportional and tensile strength.The corrosion resistance of stainless steel pipes was excellent,the surface was not corroded after copper-accelerated acetic acid-salt spray(CASS)testing.The mechanical properties of stainless steel pipes before and after freezing were not significantly difference,which showed that thematerial strength of stainless steel pipe was capable of withstanding the pressure caused by the volumeincrease of the frozen water.