DIN 1629 carbon seamless steel pipes

DIN 1629 carbon seamless steel pipes

DIN 1629 Seamless Steel pipe Of Non Alloys Steels are made of unalloyed steels, it's main grades are St 37.0, St44.0, St52.0.

What is DIN 1629?

DIN 1629 is a German standard that specifies the requirements for seamless circular steel tubes of non-alloy steels. These tubes are primarily used for mechanical and general engineering purposes, but they are not suitable for heat treatment or pressure purposes. The key points about DIN 1629 include:

DIN 1629 is the standard specifies the Seamless Circular Tubes of Non Alloys Steels with Special Quality Requirements.

DIN 1629 applications the overheated boilers, as minimum thickness ferrite and seamless steel pipes, and as heat exchangers via austenitic pipes.

Material Grades

Dimensions

The standard specifies the outer diameter, wall thickness, and permissible tolerances for the tubes.

Mechanical Properties

The mechanical properties include tensile strength, yield strength, and elongation, which vary according to the material grade.

Chemical Composition

The steel used must meet specific chemical composition limits, including carbon, manganese, phosphorus, and sulfur content.

Manufacturing Process

Tubes must be manufactured using a seamless process and may be either hot-finished or cold-finished.

Testing Requirements

Various tests are required to ensure the quality of the tubes, including tensile tests, flattening tests, and hardness tests.

Note

Hollow bar DIN1629 ST52

Hollow bar DIN1629 ST52

Hollow bar DIN1629 ST52

Hollow bar DIN1629 ST52

Field of application

1.1 This standard applies to seamless circular tubes and pipes(hereinafter briefly referred to as "tubes") made of unalloyed steels as listed in table 1. These tubes are predominantly used in the constructin of chemical plant, vessels, pipework and for general mechanical engineering purposes. They are designed to meet high performance requirements. Normally there are no limiting vaiues or the maximum permissible working pressure of these tubes. The permissi l working temperature shall not exceed 300℃ are specified in Appendix A.)

The limits of application and other specifications given in this standard shall apply except in cases here other specifications are contained in codes of practice for specific fields of application, e.g. the Technische Regeln fur Dampfkessel (TRD) (Technical rules on steam boilers) or the Technische Regeln fur Druckbehalter (TRB)

(Technical rules on pressure vessels), AD-Merkblatter (AD Instrucation sheets).

Chemical composition of steels for seamless circular tuves subject to special repuirements

steel grade Type of
deoxidization
(R, killed
(including
semi-killed))
(RR, fully killed)
chemical composition,
% by mass
Symbol Material number C P S N¹) Addition
of nitrogen
fixing elements
(e.g.not less than
0,020% AItotal
St37.0 1.0254 R 0.17 0.040 0.040 0.009²) -
St44.0 1.0255 R 0.21 0.040 0.040 0.009²) -
St52.0³) 1.0421 RR 0.22 0.040 0.035 - Yes

1) A content in excess of the maximum value started is permitted if a phosphorus content less than the maximum specifled by 0,005% P per 0,001% N is observed. However, the nitrogen content shall not exceed a value of 0.012% in the cast analysis and 0,014% in the product analysis.

2) The specified maximum values do not apply if the steels are supplied with the RR (instead of R) type of deoxidization

3) The content shall not exceed 0.55% Si and 1,06% Mn in the cast analysis or 0,60% Si and 1,70% Mn in the product analysis

table 3. Amounts by which the chemical composition in the product analysis may deviate from the limiting values applicable to the cast analysis {see table2}

Element Amount by which the product analysis
may deviate from the limiting values
applicable to the analysis
% by mass
C +0,02
P +0,010
S +0,010
N +0,001¹)

¹) A contant in excess of the maximum value stated is permitted if a phosphorus content less than the maximum specified by 0,005% P per 0,001% N is observed. However, the nitrogen contant shall not exceed a value of 0,012% in the cast analysis and 0,014% in the product analysis (this does not apply to the RR type of deoxidization.

table 4. Mechanical properties of tubes in the as delivered condition at room ternperature For wall thickness exceeding 65 mm, the values shall be agreed at the time of ordering

Steel grade Upper yield stress
ReH
for wall thicknesses, in mm,
Tensile strangth
Rm
N/mm²
Elongation after fracture
A5
Symbol Material 
number
up to 16 over 16
up to 40
over 40
up to 65
lonigtudinal transverse
St 37.0 1.0254 235 225 216 350²) to 480 25 23
St 44.0 1.0256 275¹) 265¹) 255¹) 420²) to 550 21 19
St 52.0 1.0421 355 345 335 500²) to 650 21 19

Steel-chemical composition (DIN1629)

Grade C max Si max Mn P max S max
St 35 0.17 0.35 ≥0.40 0.025 0.025
St 45 0.21 0.35 ≥0.40 0.025 0.025
St 52 0.22 0.55 ≤1.60 0.025 0.025

Mechanical Properties(Mpa)

Steel grade BK BKW BKS GBK NBK
Yield strength Rm N/mm min Elongation% min Yield strength Rm N/mm min Elongation % min Yield strength Rm N/mm min Tensile Strength ReH N/mm min Elongation % min Yield strength Rm N/mm min Elongation % min Yield strength Rm N/mm min Tensile Strength ReH N/mm min Tensile Strength ReH N/mm min
St35 480 6 420 10 420 315 14 315 25 340-470 235 25
St45 580 5 520 8 520 375 12 390 21 440-570 255 21
St52 640 4 580 7 580 420 10 490 22 490-630 355 22

¹) For cold f inished tube in the NBK condition (annealed above the upper transformation point under shielding gas or in a vacuum), minimum values of yield stress lower than these valued by 20N/mm² are permitted.

²) For cold finished tubes in the NBK condition, minimum values of tensile strength lower than these values by 10N/mm² are permitted.

The main products of steel / steel grade

Size range(mm)

Din 1629 seamless steel pipes application fields are: chemical plant, vessels, pipework construction and for common mechanical engineering purposes. Normally DIN 1629 standard are manufactured with no limiting working pressure values. Working temperature is limited below 300℃.

DIN steel heat exchangers tubes

DIN steel heat exchanger tubes, meeting German Industrial Standards, are constructed from high-temperature and corrosion-resistant steel, specifically designed for efficient heat exchange applications.

【H】 Ceramic lined pipe

Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.

【H】 Cast basalt lined steel pipe

Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.

【H】 Ceramic Tile Lined Pipes

Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.

【H】 Rare earth alloy wear-resistant pipe

The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.

【H】 Tubes Erosion Shields

Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.

【H】 ASTM A213 T91 Alloy Tube

The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.