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  無縫管分熱軋和冷軋（撥）無縫管兩類。今天我們山東無縫鋼管廠就來講一下如何將他們區(qū)別。

  熱軋無縫鋼管分一般鋼管，低、中壓鍋爐鋼管，高壓鍋爐鋼管、合金鋼管、不銹鋼管、石油裂化管、地質(zhì)鋼管和其它鋼管等。

  冷軋無縫鋼管（GB3639-2000）是用于機械結(jié)構、液壓設備的尺寸精度高和表面光潔度好的冷拔或冷軋精密無縫管。冷軋無縫鋼管除分一般鋼管、低中壓鍋爐鋼管、高壓鍋爐鋼管、合金鋼管、不銹鋼管管、石油裂化管、其它鋼管外，還包括碳素薄壁鋼管、合金薄壁鋼管、不銹薄壁鋼管、異型鋼管。熱軋無縫管外徑一般大于32mm，壁厚2.5-75mm，冷軋無縫管處徑可以到6mm，壁厚可到0.25mm，薄壁管外徑可到5mm，壁厚小于0.25mm，冷軋比熱軋尺寸精度高。

  1，從尺寸精度上面看，冷軋鋼管的尺寸好，精度高。

  2，從外觀上面看，冷軋鋼管的表面光亮，熱軋鋼管的表面有明顯的氧化皮或紅銹。

  3，從口徑尺寸上面看，冷軋鋼管的口徑比熱軋鋼管的尺寸小（主要是機械不同，各有所專）

  4，從價格上面看，冷軋鋼管比熱軋鋼管貴1000-2000一噸（千萬不可以貪便宜）

  5，從用途上面看，熱軋鋼管用在流體輸送，機械結(jié)構等對尺寸要求不高的場合，冷軋鋼管用在精密儀器，液壓系統(tǒng)，氣動。。。等要求高的地方。熱軋無縫管外徑一般大于32mm，壁厚2.5-75mm，熱軋鋼管是直接從管坯加工而成型的，冷軋無縫鋼管外徑可以到6mm，壁厚可到0.25mm，薄壁管外徑可到5mm壁厚小于0.25mm，冷軋比熱軋尺寸精度高。冷軋是圓鋼經(jīng)過穿孔冷卻之后進行冷加工制成標準尺寸的鋼管而熱軋是圓鋼穿孔后在沒有冷卻之前就軋制成標準的尺寸。

  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.