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 热轧无缝钢管经调质处理后，与轧态相比各尺寸参数均发生变化，导致下道加工工序无法正常进行或无法满足交货技术条件。通过对不同规格的样管在现场进行跟踪测量各项尺寸参数，分析数据后表明，对不同规格的钢管，热处理工序对尺寸变化的影响程度不同。轧制尺寸公差的合理控制能抵消因热处理而引起的附加尺寸变形，在轧制小规格无缝钢管时，壁厚按负公差控制，外径按公差中线控制；在轧制大口径厚壁无缝钢管时，外径应按负公差控制，壁厚按正公差控制，能使成品钢管各项尺寸参数达到最终标准要求。

Effect of Heat Treatment on Dimensional Changes of Seamless Steel Pipe

Compared to the rolled state,all the parameters of the hot rolling seamless steel pipe changed after quenching and tempering operation,which made the subsequent processing unable to operate normally meet the delivery technical conditions.Track and measure different specifications of the steel pipes in the mill,the results show that,for different dimensions of steel pipe,the dimensional changes with heat treatment process show a different degree of influence.The reasonable control of the rolling tolerance to offset the additional size of the deformation was caused by heat treatment,for rolling the smaller size seamless steel pipe,the wall thickness tolerance were controlled by the negative control,and outside diameter by the center line of the tolerance.For large-diameter thick-walled seamless steel pipe,diameter tolerance should be accorded with the negative control,and the wall thickness by the tolerance control,using this method can effectively guarantee the size parameters of the steel pipe to meet the ultimate standard.