天津方管市场价格仍将维持震荡偏弱运行方管本周方管行情回顾：周初开市期螺保持高位震荡走势，但现货市场并不配合，终端 用户心态较为谨慎维持按需采购，中间商实际成交中亦以优惠让利出货为主。此后，期螺一路震荡下行，市场观望情绪浓厚，同时近期连续大雾天气加上钢坯下移因 素叠加导致市场成交比较惨淡，仅个别低价有成交，市场持续走弱。周中，期…

镀锌方管热处理的十个要点：一、镀锌方管及夹具在热处理前均应清除油污、残盐、油漆等外来物;二、在真空炉中首次使用的夹具，应预先在不低于工件所要求的真空度下进行除气净化处理;三、在热处理过程中易变形工件，应在专用夹具上进行加热。预热的方法有：一次预热为800℃，二次预热为500-550℃和850℃，一次预热升温度速度应限制;

Ten key points for heat treatment of galvanized square tubes are as follows: 1. Before heat treatment, galvanized square tubes and fixtures should remove foreign substances such as oil, residual salt and paint; 2. Fixtures first used in vacuum furnaces should be degassed and purified in advance at the vacuum required by the workpiece; 3. Workpieces easily deformed during heat treatment should be heated on special fixtures. The preheating methods are as follows: primary preheating is 800 C, secondary preheating is 500 - 550 C and 850 C, and the speed of primary preheating should be limited. 四、对于形状复杂或截面有急剧变化以及有效厚度较大的工件，应进行预热;五、有凹槽不通孔的工件、铸件和焊接件以及加工成形的不锈钢工件，一般不宜在盐浴炉中加热;六、镀锌方管加热应有足够的保温时间，可根据工件有效厚度和条件厚度(实际厚度乘以工件形状系数);

4. For workpieces with complex shapes or sharp changes in cross sections and large effective thickness, preheating should be carried out; 5. Workpieces with grooves and no through holes, castings and welds, and stainless steel workpieces processed and formed, generally, should not be heated in a salt bath furnace; 6. Galvanized square tubes should be heated with sufficient holding time, which can be multiplied by the effective thickness and conditional thickness of the workpiece (actual thickness multiplied by workpiece thickness). Shape coefficient;

七、马氏体不锈钢和耐热钢镀锌方管淬火冷至室温后方可进行清洗、深冷处理或回火，焊接和其后的热处理之间的时间间隔不应超过4小时;八、根据镀锌方管要求和表面状况采用碱洗、水溶性清洗剂、氯溶剂喷砂，喷丸等方法进行清理;九、矫正后应在低于原回火温度下进行去应力退火，形状复杂或尺寸要求严格工件，矫正后在回火时用定形夹具结合回火进行矫正;十、当镀锌方管力学性能不合格时，可重复热处理，但重复淬火或固溶次数一般不超过二次。镀锌方管的补充回火不算作重复处理。淬火状态或低温回火后的马氏体不锈钢和耐热钢工件，重复淬火前应进行预热，退火或高温回火。

7. After quenching and cooling to room temperature, galvanized square tubes of martensitic stainless steel and heat-resistant steel can be cleaned, cryogenically treated or tempered. The time interval between welding and subsequent heat treatment should not exceed 4 hours. 8. According to the requirements and surface conditions of galvanized square tubes, alkali washing, water-soluble cleaning agent, chlorine solvent sandblasting, shot blasting and other methods should be used for cleaning. 9. After rectification, the temperature should be lower than the original tempering temperature. Stress-relief annealing is carried out under the degree of stress, and the workpiece with complex shape or strict size is required. After correction, the workpiece is corrected by setting fixture combined with tempering when tempering. 10. When the mechanical properties of galvanized square tubes are not up to standard, heat treatment can be repeated, but the number of repeated quenching or solid solution does not exceed twice. Supplementary tempering of galvanized square tubes is not regarded as repetitive treatment. Martensitic stainless steel and heat-resistant steel workpieces after quenching or low temperature tempering should be preheated, annealed or tempered at high temperature before repeated quenching.

预计下周中南地区镀锌方管价格震荡偏弱运行…方管本周中南地区镀锌方管市场价格震荡向下，市场方面，本周周一受原料拉涨影响镀锌方管价格小幅跟涨外，周二到周五镀锌方管价格开始震荡下行。31日，关于唐山6月份环保限产措施出版，限产或对 原料钢坯价格形成一定支撑，然6月份中南各地将进入季节性需求淡季，下游终端对镀锌方管消耗将放缓，或对成品材价格形成一定压力。五月… 天津方管价格窄幅调整厂家资源缺货比较严重…方管本周天津方管市场价格窄幅调整，成交清淡。临近春节，本地及周边需求再度减弱，据了解，目前本地方管厂家资源缺货比较严重，主流规格存在断档现象，目前主要流通资源以包钢为主，唐钢、首钢、鞍 钢、本钢等钢厂资源偏少，调坯厂资源以轧一、天铁为主，另外，手中资源较少方管厂家预计下周开始提前放假，个别大户17号小年开始…