方管和矩形管冷弯成型时不同的特点方管冷弯方管、冷弯矩形管是通过外辊与管坯外壁的单向接触形成弯矩使带料弯折,冷弯会使弯折线产生压缩,压缩效应使弯折线纵向伸长,弯折处金属出现堆积变厚,这就是冷弯的压缩/增厚效应。Cold-formed square pipe and cold-formed rectangular pipe bend the strip through the unidirectional contact between the …

南京市场方管价格下跌，成交一般。早盘螺纹钢期货低开低走。唐山方坯跌20元，现普碳方坯含税出厂3510元。从当地贸易商了解， 贸易战对市场心态影响较大，除刚需低价有所成交，大多仍处在观望。商家进少出多，以完成销售任务为主。钢厂库存尚无压力，不过价格下调较之前有所放大。综 上所述，预计明日南京市场或继续回落。

In Nanjing market, prices fell and transactions were normal. Early-trading threaded steel futures open low. Tangshan billet fell 20 yuan, and now ordinary carbon billet with tax is 3510 yuan out of the factory. From the local traders, the trade war has a great impact on the market mentality. Most of them are still on the sidelines, except for the bargain just needed at a low price. Businessmen come in less and go out more, mainly to complete sales tasks. There is no pressure on steel mill stocks, but the price reduction has been enlarged. In summary, the Nanjing market is expected to continue to decline tomorrow. 价格方面：截止发稿时，永钢、沙钢三级大螺纹4210元(吨价，下同)，跌50元。

Price: Up to the time of submission, Yonggang and Shagang three-level large threads 4210 yuan (ton price, the same below), down 50 yuan.

国内方管市场价格或盘整趋弱厂家成交较为一…方管本周方管市场价格稳中调整。截至12月13日，国内重点城市16-25mm普板均价3788元(吨价，下同)，较上个交易日下跌2元，较上周同期上涨17元，较上月同期上涨88元。本周黑色系市场表现强势，持续拉涨，带动方管现货小涨趋强，不过，周后期市场表现差强人意，价格呈现回落态势。周初，虽期货拉升，但部分区域重污染天气影 响，雾霾… 长沙镀锌方管价格或将偏强运行厂家限价力度…方管现货方面，长沙镀锌方管市场价格明显上涨。成交方面，连日来长沙地区镀锌方管到货量少，需求正常释放，库存消耗较快。由于价格的持续上行，有部分方管厂家采取了停单操作，捂盘待涨。部分方管厂家反映直发比例增大，市场整体出货情况一般。市场心态方面，连日来期螺持续高位盘整的态势，方管厂家反映库存水平较低，方管厂家限…