If the valve body material can be welded, but very different thermal expansion coefficient, or changes in operating temperature range of a larger thread junction closure weld must be honey.
如果阀体的材料是可以焊接的，但膨胀系数差异很大，或者工作温度的变化幅度范围较大，螺纹连接部必须进行蜜封焊。
If the produced junction is sound electrically and mechanically, the type of weld or impurities in the junctions itself have no effect on the accuracy and certainly no improvement in accuracy.
如果所产生的焊点(接头)在电力和机械方面都比较可靠，接头的焊接类型或接头内部的杂质丝毫不会降低焊接精度，当然也不会提高焊接精度。
If the produced junction is sound electrically and mechanically, the type of weld or impurities in the junctions itself have no effect on the accuracy and certainly no improvement in accuracy.
如果所产生的焊点(接头)在电力和机械方面都比较可靠，接头的焊接类型或接头内部的杂质丝毫不会降低焊接精度，当然也不会提高焊接精度。
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