North-pipe manufactures high precision cold drawn and cold rolled seamless steel tubes for auto parts in transmission, powertrain, steering and suspension systems. With outstanding and stable quality, North-pipe is serving a variety of leading domestic and international OEMs as well as mid to high-end aftermarket auto parts manufacturers.

High Precision Cold Rolled Seamless Tube Used for Automotive

Size Range: O.D 16-245mm, WT 1-32mm


Executive Standard:

GB/T3639, Cold-drawn or cold-rolled precision seamless steel

DIN2391, Seamless precision steel tubes

DIN2393, Welded Precision Steel Tubes

EN10305-1, Steel tubes for precision applications Part 1: Seamless cold drawn tubes

EN10305-2, Cold drawn steel tubes for precision applications Part 2: Welded cold drawn tubes

ASTM A519, Seamless Carbon and Alloy Steel Mechanical Tubing

ASTM A513, Electric-Resistance-Welded Carbon and Alloy Steel Mechanical Tubing

JIS G3445, Carbon Steel Pipe For Mechanical Purpose

JIS G4051, Carbon Steels for Machine Structural Use

According to customer’s specific requirements


Steel Grade:

10#, 20#, 35#, 45#, 55#, Q355B, 25Mn, 16MnCr5, 20MnCr5, 30CrMo, 35CrMo, 42CrMo, 20Cr, 40Cr, 20CrNiMo ; ST37, ST45, ST52, 34CrMo4, 42CrMo4 ; E235, E255, E355 ; 1010, 1020, 1026, 1035, 1045, 1050, 4130, 4140, 8620 ; STKM 11A, STKM 12B, STKM 13C, STKM 14B ; S10C, S20C, S35C, S45C and etc.


Delivery Condition:

Cold drawn/hard (+C) (BK)

Cold drawn/soft (+LC) (BKW)

Cold drawn and stress relieved (+SR) (BKS)

Annealed (+A) (GBK)

Normalized (+N) (NBK)

Quenched and Tempered (QT)



Optimized mechanical properties enabling easy bending, flaring, flattening and other processing

Good surface roughness suitable for electrophoresis, coating, galvanization and chroming processing

High precision

Excellent microstructure