DIN2391 St37.4 Precision Tubes

• Type: Seamless
• Technique: Cold Drawn
• Material: Carbon Steel
• Surface Treatment: Oiled
• Usage: Boiler Pipe, Hydraulic/Automobile Pipe, Machinery Industry
• Section Shape: Round
• Model NO.: KM-20200721
• Transport Package: in Bundle or Wooden Box.
• Specification: 10~219.1mm
• Trademark: KINGMETAL
• Origin: China
• HS Code: 7304319000
• Production Capacity: 1000 Tons Per Month

Product Description

DIN2391 St37.4 NBK/DIN 2391 St35 BK

Size Range

OD 10mm-219.1mm

WT 2mm-30mm

Length 1-12 m
 

1. Seamless cold-drawn precision steel pipes E235N (St 37.4)

and E355N (St 52.4) according to EN 10305-4

a. E235N (St 37.4) - NBK

- Normalized, phosphated and oiled inside and outside

b. E235N (St 37.4) - NBK/ZN

- Normalized, electric zinc plated with Cr-VI-free passivation

c. E355N (St 52.4) - NBK

- Normalized, phosphated and oiled inside and outside

d. E355N (St 52.4) - NBK/ZN

- Normalized, electric zinc plated with Cr-VI-free passivation

2. Austenitic stainless steel pipes, seamless, cold-drawn 316L

(1.4404) according ASTM-standards

a. AISI 316L - metric sizes Fully annealed, scale free

b. TP 316L - schedule sizes Fully annealed, scale free

 

DIN 2391/C (DIN EN 10305-4) - Steel tubes for precision applications -

Technical delivery conditions - Part 4: Seamless cold drawn tubes for

hydraulic and pneumatic power systems

DIN 2445/2 - Seamless steel tubes for dynamic loads - Part 2: Steel

tubes for precision application in fluid systems, 100 bar to 500 bar

Material Specifications:

ST37.4 (E235N)

ST52.4 (E355N)

Finishing:

NBK, Normalized, phosphated and oiled inside and outside. The tubes are annealed above the upper transformation

point in a controlled atmosphere or under vacuum

Recommended Bend Radius

A bend radius of 3x the external tube diameter is recommended for cold

bending of tubes with tube benders or by hand. (As per Figure 1)

Welding Suitability

Tubes of ST37.4, ST52.4 are suitable for welding according to usual techniques.

The welding filler should be selected in accordance with DIN EN 1600 and DIN

EN 12072 part 1 taking into account the type of application and the welding

technique.

DIN 2391 Mechanical properties

 

		The final delivery condition	Cold drawn(Mandatory) BK^1)		Cold drawn(Soft)  BKW^1)		Cold Drawn and Stress Release (BKS)			Anneal (GBK)^1)		Normalizing (NBK)^1)
Kinds of Steel			Tensile	Elongation	Tensile	Elongation	Tensile	Yield point	Elongation	Tensile	Elongation	Tensile	Yield point	Elongation
Steel grade	Material number		No less than
			Rm	A5	Rm	A5	Rm	ReH	A5	Rm	A5	Rm	ReH^2)	A5
			N/mm^2	%	N/mm^2	%	N/mm^2	N/mm^2	%	N/mm^2	%	N/mm^2	N/mm^2	%
St35	1.0308		--	--	--	--	--	--	--	--	--	340~470	235	25
St37.4	1.0255		480	6	420	10	420	315	14	315	25	350~480	235	25
St45	1.0408		580	5	520	8	520	375	12	390	21	440~570	255	21
St52	1.0580		640	4	580	7	580	420	10	490	22	490~630	355	22
St52.4	1.0581		--	--	--	--	--	--	--	--	--	500~650	355	21

 

EN 10305-1 Mechanical properties

 

		The final delivery condition	Cold drawn (Mandatory) +C		Cold drawn (Soft)+LC		Cold Drawn and Stress Release (+SR)			Anneal (+A)		Normalizing (+N)
			Tensile	Elongation	Tensile	Elongation	Tensile	Yield point	Elongation	Tensile	Elongation	Tensile	Yield point	Elongation
Steel grade	Material number		No less than
			Rm	A5	Rm	A5	Rm	ReH	A5	Rm	A5	Rm	ReH^2)	A5
			N/mm^2	%	N/mm^2	%	N/mm^2	N/mm^2	%	N/mm^2	%	N/mm^2	N/mm^2	%
E235	1.0308		480	6	420	10	420	350	16	315	25	340~480	235	25
E255	1.0408		580	5	520	8	520	375	12	390	21	440~570	255	21
E355	1.0580		640	4	580	7	580	450	10	450	22	490~630	355	22

 

GB3639 Mechanical properties

 

	The final delivery condition	Cold drawn (Mandatory) BK^1)		Cold drawn (Soft)  BKW^1)		Cold Drawn and Stress Release (BKS)		Anneal (GBK)^1)		Normalizing (NBK)^1)
		Tensile	Elongation	Tensile	Elongation	Tensile	Elongation	Tensile	Elongation	Tensile	Yield point	Elongation
Steel grade		No less than
		Rm	A5	Rm	A5	Rm	A5	Rm	A5	Rm	ReH2)	A5
		N/mm^2	%	N/mm^2	%	N/mm^2	%	N/mm^2	%	N/mm^2	N/mm^2	%
10		410	6	375	10	335	12	335	24	335	205	24
20		510	5	450	8	430	10	390	20	410	245	20
35		590	4	550	6	520	8	510	17	530	315	17
45		645	4	630	5	610	7	590	14	600	355	14