Product Item

DIN 2391 st52 BKS honed and SRB precision seamless steel tube for hydraulic

Outer Diameter

30mm~250mm

Wall Thickness

2mm~30mm

Material Grade

10#-45#, 16Mn, Q195-Q345, ST35-ST52, STB35-STB42, 20#, 45#, 16Mn, Q345, ST35, St45, St52, St52.4, STB42, 

16Mn,St52,10#-45#,ST35-ST52

Standard

ASTM, DIN, ASTM A1020-2002, DIN 2391

Application

Hydraulic Pipe, Hydraulic cylinder, automobile, oil drilling, 

textile machinery

Certificate

ISO9001:2008 

Process Method

Cold Drawn/ Cold Rolled

Surface Finish

Annealed, Pickled

Package

According to the customer’s requirement 

Delivery Time

10days more or according to the customer’s requirement 

Price Item

FOB CIF EXW

Payment

T/T(30% in advance, 70% against the BL Copy) and L/C 

at sight or as negotiation

ID tolerance

H8,H9b H10 or as customized 

Surface roughness

Ra0.2~0.8µm

Finally supply condition

BK BKS BKW NBK GBK

Mechanics performance:

Material

Tensile strength

Yield strength

Elongation

Hardness

CK20/20#/AISI1020

>520 N/ mm2

>375 N/mm2

>15%

>85HB

CK45/45#/AISI1045

>600 N/ mm2

>520 N/ mm2

>15%

>85HB

ST52/16Mn/Q345D

>600 N/ mm2

>520 N/ mm2

>15%

>85HB

25Mn/STKM 13C-T

>600 N/ mm2

>530 N/ mm2

>15%

>85HB

Variety :

Processing

Cylinder 
Diameter

Straightness

Size 
Accuracy

W.T/mm

Inner Bore Roughess

Cold drawn/cold rolled

ID30-250

0.3

H9-H11

±10%

0.4~1.6um

Honed tube

ID50-250

0.3

H7-H9

±10%

<0.4um

Tolerance on ID:

No.

Inside diameter
(mm)

ID machining allowance
(mm)

1

300-80

0.5-0.8

2

81-125

0.7-1.1

3

125-200

0.9-1.2

4

200-250

1-1.5

Other dimension can be customize