Seamless pipes are extensively applied for the nuclear device, gas, petrochemical, ship building and boiler industries.

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  Boiler and superheater seamless carbon steel pipe
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  Mechanical tubes
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  Fluid tubes
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  Ship building tubes
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  Bearing pipes
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  Seamless pipes for low and medium pressure service
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  Seamless pipes for high temperature and pressure service
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  Honed Tube
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  Structural seamless pipes
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  Marine Seamless Steel Pipe
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  Seamless Ferrite Alloy and Austenitized Alloy Tube
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  Heat Exchanger Tubes
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  Steel Tubes for Mechanical and Automobile
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  Seamless Pipes and Tubes for Pressure Applications
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  Line pipes used in sour service environment
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  Seamless steel tubes for low-temperature service
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  Seamless steel pipes for low and medium pressure service

Seamless steel pipe is alos called CDS pipes (Cold drawn seamless pipe). It’s is used widely in maching parts, shafts, bearings, cylinders having strength of 75000 PSD tensile. It is a solid carbon steel rod which is pushed on to the mandrel to form the shape of tube. It is availabe in different sizes.

Cold drawn seamless steel tubes process

round tube → heating → ​​perforation → Heading → ​​annealing → ​​pickling → ​​oiled (copper) → multi-pass cold drawn (cold rolled) → blank tube → heat treatment → straightening →hydrostatic testing (testing) → mark → storage.

The general cold strip mills, volume should go through continuous annealing (CAPL unit) to eliminate cold hardening and rolling stress, or batch annealing reach the mechanical properties of the corresponding standard specifies. Cold rolled steel surface quality, appearance, dimensional accuracy better than hot-rolled plate, and right-rolled thin product thickness is about 0.18mm, so the majority of users favor.

Hot-rolled seamless steel pipe production base deformation process can be summarized as three stages: perforation, extension and finishing.

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Hot rolled seamless steel pipe deformed process

Hot-rolled seamless steel pipe production base deformation process can be summarized as three stages: perforation, extension and finishing.

The main purpose of the perforation process is to become a solid round billet piercing hollow shell. Capillary in the specifications, accuracy and surface quality can not meet the requirements of the finished product, further improvements are needed to deform the metal through. The main purpose of the stretching machine is further reduced sectional view (main compression wall) for a larger axial extension, so that the capillary improved dimensional accuracy, surface quality and organizational performance.

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Condition on delivery:

Term	Symbol	Explanation
Cold-finished/hard (cold-finished as-drawn)	BK	No heat treatment after the last cold-forming process. The tubes therefore have only low deformability.
Cold-finished/soft (lightly cold-worked)	BKW	After the last heat treatment there is a light finishing pass (cold drawing) With proper subsequent processing, the tube can be cold-formed (e.g. bent, expanded) within certain limits.
Annealed	GBK	After the final cold-forming process the tubes are annealed in a controlled atmosphere or under vacuum.
Normalized	NBK	The tubes are annealed above the upper transformation point in a controlled atmosphere or under vacuum.

The general cold strip mills, volume should go through continuous annealing (CAPL unit) to eliminate cold hardening and rolling stress, or batch annealing reach the mechanical properties of the corresponding standard specifies. Cold rolled steel surface quality, appearance, dimensional accuracy better than hot-rolled plate, and right-rolled thin product thickness is about 0.18mm, so the majority of users favor.

Cold rolled steel coil substrate products deep processing of high value-added products. Such as electro-galvanized, hot dip galvanized, electro-galvanized fingerprint resistant, painted steel roll damping composite steel, PVC laminating steel plates, etc., so that the excellent quality of these products has a beautiful, high resistance to corrosion, has been widely used.

Cold rolled steel coil finishing after annealing, cut the head, tail, trimming, flattening, smooth, heavy volume, or longitudinal clipboard. Cold-rolled products are widely used in automobile manufacturing, household electrical appliances, instruments, switches, buildings, office furniture and other industries. Steel plate strapping package weight of 3 to 5 tons. Flat sub-volume typically 3 to 10 tons / volume. Coil diameter 6m.