DIN 2391 Bright Annealing Precision Seamless Steel Tube

DIN 2391 Bright Annealing Precision Seamless Steel Tube

Get Latest Price

Payment Type:	L/C,D/P,T/T
Incoterm:	CFR,EXW,CIF,FOB
Transportation:	Ocean,Land,Express
Port:	Tianjin,Shanghai,Qingdao

Contact Now

Product Description

Product Attributes

Model No.: DIN2391 St35 St45 St52

Standard: Din

Material: St35-St52

Section Shape: Round

Place Of Origin: China

Application: Fluid Pipe, Boiler Pipe, Structure Pipe, Hydraulic Pipe

Production Process: Cold Drawn

Certification: Ce

Whether Alloy: Is Alloy

Tolerance: ±1%

Category: Seamless Steel Pipe

Processing Service: Cutting, Punching, Decoiling, Welding, Bending

Packaging & Delivery

Selling Units	:	Ton
Package Type	:	Standard marine packaging, or as required by the customer
Picture Example	:

Honed Steel Tube

ASTM A53 A106 Round Carbon Seamless Steel Pipe



Product Description

DIN2391 seamless precision steel tubes

DIN 2391 standard specifies the Seamless steel tubes used for Mechanical and Automobile.

The main products of steel / steel grade: DIN2391-1(ST35, ST45, ST52).

Scope

DIN2391 Part 2 specifies dimensions for cold finished, seamless precision steel tubes and is to be used in conjunction with DIN2391 part2 which states the relevant technical delivery conditions. The preferred sizes listed in standard are mainly used in mechanical and automotive engineering.

Where steel tubes of dimensions specified in this standard are to comply with the technical delivery conditions listed in subclause 1.2 of DIN 2391 Part 2.

DIN 2391 seamless precision tubes applications – Used in Hydraulic & pneumatic cylinder, Mechanical and Automotive engineering.

Chemical Composition (%) of DIN2391

Standard	Grade		Chemical Components (%)
Standard	Symbol	Material No.	C	Si	Mn	P	S
DIN2391	St 30 Si	1.0211	≤0.10	≤0.10	≤0.55	≤0.025	≤0.025
	St 30 Al	1.0212	≤0.10	≤0.05	≤0.55	≤0.025	≤0.025
	St 35	1.0308	≤0.17	≤0.35	≥0.40	≤0.025	≤0.025
	St 45	1.0408	≤0.21	≤0.35	≥0.40	≤0.025	≤0.025
	St 52	1.058	≤0.22	≤0.55	≤1.60	≤0.025	≤0.025

Delivery Conditions

The tubes shall be manufactured from cold drawn or cold rolled processes. The tubes shall be supplied in one of the delivery conditions as follows:

Designation	Symbol	Description
Cold finished (hard)	BK	Tubes do not undergo heat treatment following the final cold forming and thus, have a rather high resistance to deformation.
Cold finished (soft)	BKW	The final heat treatment is followed by cold drawing involving limited deformation. Appropriate further processing allows a certain degree of cold forming (e.g. bending, expanding).
Cold finished and stress-relieved	BKS	Heat treatment is applied following the last cold forming process. Subject to appropriate processing conditions, the increase in the residual stresses involved enables both forming and machining to a certain degree.
Annealed	GBK	The last cold forming process is followed by annealing in a controlled atmosphere.
Normalized	NBK	The last cold forming process is followed by annealing above the upper transformation point in a controlled atmosphere.

Delivery Condition Symbol in accordance with EN10305 and DIN2391.

Symbol in accordance with EN 10305	Symbol in accordance with DIN2391
+C	BK
+LC	BKW
+SR	BKS
+A	GBK
+N	NBK

Mechanical Properties

Steel Grade		Minimum values for the delivery condition
Steel Name	Steel Number	BK		BKW		BKS			GBK		NBK
		Rm	A %	Rm	A %	Rm	ReH	A %	Rm	A %	Rm	ReH	A %
		Mpa	A %	Mpa	A %	Mpa	Mpa	A %	Mpa	A %	Mpa	Mpa	A %
St 30 Si	1.0211	430	8	380	12	380	280	16	280	30	290 to 420	215	30
St 30 Al	1.0212	430	8	380	12	380	280	16	280	30	290 to 420	215	30
St 35	1.0308	480	6	420	10	420	315	14	315	25	340 to 470	235	25
St 45	1.0408	580	5	520	8	520	375	12	390	21	440 to 570	255	21
St 52	1.0580	640	4	580	7	580	420	10	490	22	490 to 630	355	22

Inspection and test list for the DIN 2391 Standard

Inspection or test types	Test frequency
Inspection or test types	Internal test	Acceptance test
Chemical analysis	M	M
Tensile testing	M	One per tested batch
Flattening test or extension test	M	Two per tested batch
Dimension verification	M	M
Visual inspection	M	M
NDT in order to identify leaks	Individual	Individual

St35 St45 St52

Marking

The following marking shall be shown on a label attached to the bundle:

the manufacturer’s name or trade mark;
the specified dimensions;
the number of this European Standard;
the steel name or number;
the cast number;
the delivery condition;
in the case of specific inspection, an identification number (e. g. order or item number) which permits the correlation of the product or delivery unit to the related document.

Protection and Packing:

Packed in wooden box or bundles protected with plastic paper, and suitably protected for sea-worthily delivery or as requested.
The tubes shall be delivered with a temporary corrosion protection. The type of protection shall be at the discretion of the manufacturer.