无缝管分热轧和冷轧（拨）无缝管两类。今天我们山东无缝钢管厂就来讲一下如何将他们区别。

  热轧无缝钢管分一般钢管，低、中压锅炉钢管，高压锅炉钢管、合金钢管、不锈钢管、石油裂化管、地质钢管和其它钢管等。

  冷轧无缝钢管（GB3639-2000）是用于机械结构、液压设备的尺寸精度高和表面光洁度好的冷拔或冷轧精密无缝管。冷轧无缝钢管除分一般钢管、低中压锅炉钢管、高压锅炉钢管、合金钢管、不锈钢管管、石油裂化管、其它钢管外，还包括碳素薄壁钢管、合金薄壁钢管、不锈薄壁钢管、异型钢管。热轧无缝管外径一般大于32mm，壁厚2.5-75mm，冷轧无缝管处径可以到6mm，壁厚可到0.25mm，薄壁管外径可到5mm，壁厚小于0.25mm，冷轧比热轧尺寸精度高。

  1，从尺寸精度上面看，冷轧钢管的尺寸好，精度高。

  2，从外观上面看，冷轧钢管的表面光亮，热轧钢管的表面有明显的氧化皮或红锈。

  3，从口径尺寸上面看，冷轧钢管的口径比热轧钢管的尺寸小（主要是机械不同，各有所专）

  4，从价格上面看，冷轧钢管比热轧钢管贵1000-2000一吨（千万不可以贪便宜）

  5，从用途上面看，热轧钢管用在流体输送，机械结构等对尺寸要求不高的场合，冷轧钢管用在精密仪器，液压系统，气动。。。等要求高的地方。热轧无缝管外径一般大于32mm，壁厚2.5-75mm，热轧钢管是直接从管坯加工而成型的，冷轧无缝钢管外径可以到6mm，壁厚可到0.25mm，薄壁管外径可到5mm壁厚小于0.25mm，冷轧比热轧尺寸精度高。冷轧是圆钢经过穿孔冷却之后进行冷加工制成标准尺寸的钢管而热轧是圆钢穿孔后在没有冷却之前就轧制成标准的尺寸。

  Seamless pipe hot rolling and cold rolling (dial) seamless tube.Today we will talk about shandong seamless tube mill how to distinguish them.

  Hot-rolled seamless steel tube general steel pipe, low and medium pressure boiler pipe, high pressure boiler tube, alloy steel, stainless steel pipe, oil cracking pipe, geological steel pipe and other steel pipe and so on.

  Cold rolled seamless steel tube (GB3639-2000) is used in the mechanical structure and hydraulic equipment of high dimensional accuracy and surface finish good cold drawn or cold rolled precision seamless tube.Cold rolled seamless steel tube in addition to general steel tube, low medium pressure boiler pipe, high pressure boiler tube, alloy steel, stainless steel tube, petroleum cracking tube, steel tube, the other also includes carbon thin wall steel tube, alloy thin wall steel pipes, thin-walled stainless steel pipe, steel pipe.Generally greater than 32 mm hot rolled seamless steel tube diameter, wall thickness 2.5 75 mm, cold rolled seamless steel tube can be to 6 mm in diameter, wall thickness to 0.25 mm, to 5 mm thin wall pipe diameter, wall thickness less than 0.25 mm, cold than hot rolled high dimensional accuracy.

  1, from above, size precision cold-rolled steel pipe size, high precision.

  2, from the appearance of the above, the surface of cold rolled steel tube light, the surface of hot rolled steel pipe with obvious scale or red rust.

  3, look from above the diameter size, cold-rolled steel pipe diameter is smaller than the size of the hot-rolled steel pipe (mainly machinery, to be dedicated)

  4, from the above price, cold-rolled steel pipe more expensive than hot-rolled steel pipe 1000-2000 a tonne (never keen on gaining petty advantages)

  5, from the purpose above, hot-rolled steel works in fluid transportation, mechanical structure and so on the occasion of the size requirement is not high, cold rolled steel pipe used in precision instruments, hydraulic system, pneumatic...Such as demanding place.Generally greater than 32 mm hot rolled seamless steel tube diameter, wall thickness 2.5 75 mm, hot-rolled steel pipe is directly from the tube billet processing and forming, can reach 6 mm cold rolled seamless steel tube diameter, wall thickness to 0.25 mm, to 5 mm thin wall pipe diameter thickness less than 0.25 mm, cold than hot rolled high dimensional accuracy.Cold rolling is made of round steel for cold working after perforation cooling standard size of steel pipe and hot rolled round steel perforated before no cooling after rolling is into standard size.