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原文
Repair welding method of steel valves 1, requires Repair welding of austenitic stainless steel castings, to the ventilation, so that rapid cooling. Pearlitic and low alloy steel castings for welding carbon steel castings too large an area should be selected lee or windshield cover, to avoid cracks caused by rapid cooling. Welding a stack layer, should be immediately removed after welding residue, and along the defect centers hammering out evenly, reduce welding stresses. If the layers of the welding points (usually 3 ~ 4mm for a welding layer), then each have to be promptly removed after welding and hammer welding residue area. If the winter welding, ZG15Cr1Mo1V class pearlite steel castings, each layer also applied welding oxygen - acetylene repeated heating, and then quickly repair welding to avoid weld cracking. 2, the electrode process Welding, you should first check whether the warm-up welding, general welding shall be 150 ~ 250 ℃ drying 1h. After preheating the electrode should be set in the incubator, so that whenever they were taken. Preheat welding repeated three times, if the electrode surface of the skin have come off drugs, cracking, and rust should not be used. 3, the number of welding Pressure casting, such as the valve body by seepage pressure test, the same part of the general welding only once, not repeated repair welding, repair welding because many coarse grain steel will affect the performance of the casting under pressure, unless castings can be re-weld heat treatment. Other parts of the same non-pressure welding, repair welding general rule no more than 3 times. More than twice the same parts of the welding of carbon steel castings, weld stress relief should be handled. 4, the welding layer height Repair welding of castings generally higher than the casting surface height about 2mm in order to facilitate machining. Welding layer is too low, easily exposed after machining welding scars. Welding layer is too high, time-consuming cost materials.
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译文：
1、要求对奥氏体不锈钢铸件进行补焊时,要在通风处,使之快速冷却。对珠光体低合金钢铸件和补焊面积过大的碳钢铸件则应选背风处或用挡风板遮挡,避免快冷造成裂纹。补焊一个堆层的,补焊后应立即清除药渣,并沿缺陷中心向外均匀地锤击,降低补焊应力。若补焊分几层进行(一般3～4mm为一补焊层),则每层补焊后均要及时清除药渣和锤击补焊区域。如在冬季施焊,ZG15Cr1Mo1V类的珠光体合金钢铸件,每补焊一层还应用氧-乙炔反复加热,再迅速补焊,以避免产生焊接裂纹。 2、焊条处理补焊前,应首先检查焊条是否预热,一般焊条应经150～250℃烘干1h。预热后的焊条应置保温箱中,做到随用随取。焊条反复预热3次,若焊条表面药皮有脱落、开裂和生锈,应不予使用。 3、补焊次数承压铸件,如阀门壳体经试压渗水,同一部位一般只允许补焊一次,不能重复补焊,因为多次补焊会使钢中晶粒粗大,影响铸件的承压性能,除非铸件可以在焊后重新进行热处理。其他非承压同一部位的补焊,一般规定补焊不超过3次。同一部位的补焊超过二次的碳钢铸件,焊后应作消除应力处理。 4、补焊层高度铸件的补焊高度一般高出铸件平面2mm左右,以利机加工。补焊层太低,机加工后易露出焊疤。补焊层过高,费时费力费材料。

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