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原文
After welding cast steel valve should eliminate stress After finishing welding defects found after doing a whole has been unable to eliminate the stress tempering, defective parts can be used normally oxygen - acetylene flame local heating tempering method. The use of large neutral flame torch swinging slowly back and forth, heated to the casting surface can be seen visually dark red (about 740 ℃), heat (2min/mm, but not less than 30min). Stress relief treatment should be immediately covered with asbestos in the defects. Pearlite steel valve diameter of the defect, repair welding should also be filling in the cavity diameter asbestos, so that slow cooling. Such operations, easily and economically, but requires a certain experience welders. After welding of stainless steel castings in general no treatment, but should be in the ventilation welding, the welding area fast-cooling. Unless the welding austenitic after that change has been caused, or is re-defect. In the contract and conditions permit, should rework melting treatment. Defect area is too large and too deep for a variety of pearlite steel castings castings castings in the clearing phase and into the roughing though, but left the finishing allowance, shall be implemented after the welding process to eliminate stress. Steel tempering temperature can be set to eliminate stress 600 ~ 650 ℃, ZG15Cr1Mo1V and ZGCr5Mo tempering temperature can be set to 700 ~ 740 ℃, ZG35CrMo tempering temperature to 500 ~ 550 ℃. All steel castings, the elimination of stress tempering holding time are less than 120min, and the furnace cooled to below 100 ℃ released.
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译文：
精加工后发现的缺陷补焊后,已无法做整体消除应力回火处理,一般可采用缺陷部位氧-乙炔火焰局部加热回火方法。采用大号割炬中性火焰来回缓慢摆动,将铸件加热到表面出现目视可见暗红色(约740℃),保温(2min/mm,但不少于30min)。消除应力处理后应立即在缺陷处盖上石棉板。珠光体钢阀门通径上的缺陷,补焊时还应在通径内腔填塞石棉板,使之缓冷。此种操作,既简便又经济,但要求焊工有一定实践经验。不锈钢铸件在补焊后一般不作处理,但应在通风处施焊,使补焊区快冷。除非补焊后表明已引起奥氏体组织的改变,或属于重缺陷。在合同和条件许可下,应重做固溶化处理。缺陷面积过大过深的碳钢铸件和各种珠光体铸件,处于铸件清整阶段和虽进入粗加工、但留有精加工余量的,应在补焊后实施消除应力处理。碳钢消除应力回火温度可设为600～650℃,ZG15Cr1Mo1V和ZGCr5Mo回火温度均可设为700～740℃,ZG35CrMo回火温度设为 500～550℃。所有钢种的铸件,其消除应力回火的保温时间均不少于120min,并随炉冷却到100℃以下出炉。

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