钢对接焊接管件 技术交货条件

Steel butt-welding pipe fittings

Technical delivery conditions

DIN 2609

Formstücke zum Einschweißen; technische Lieferbedingungen

In keeping with current practice in standards published by the International Organization for Standardization (ISO), a comma has been used throughout as the decimal marker.

The symbol ■ denotes items which shall, symbol ■■ denoting items which may, be agreed upon at the time of ordering.

Contents

Page Field of application Ordering Materials Requirements 4.1 Manufacturing process 4.2 As delivered condition 4.3 Chemical composition 4.4 Mechanical properties 4.5 Weldability 4.6 Surface condition 4.7 Dimensions and tolerances

Page Testing and materials testing certificates 5.1 General 5.2 Test site 5.3 Scope of testing 5.4 Sampling and sample preparation 5.5 Test methods 5.6 Retests 5.7 Materials testing certificates Marking Complaints

1 Field of application

This standard specifies technical delivery conditions for unalloyed and alloyed steel butt-welding pipe fittings in compliance with DIN 2605 Part 1 or 2, DIN 2615 Part 1 or 2 (at present at the stage of draft), DIN 2616 Part 1 or 2, or DIN 2617. Where such fittings fall under the scope of the regulations pertaining to plants subject to mandatory inspection as referred to in section 24 of the Gewerbeordnung (German Trade Regulation), such as the Dampfkesselverordnung (German Regulation on steam boilers) or the Druckbehälterverordnung (German Pressure Vessels Regulation), then the requirements given in the relevant codes of practice, such as the Technische Regeln Dampfkessel (Codes of practice for steam boilers), the Technische Regeln Druckbehälter (Codes of practice for pressure vessels), or the AD-Merkblätter (AD Instruction sheets) shall be complied with. This also applies to fields of application where additional requirements are to be complied with.

Note. Owing to the tendency of certain materials to scale and owing to stresses under service conditions possibly deviating from those on which the specifications of this standard are based, the design temperature ranges specified in table 2 may not apply in all cases.

2 Ordering

It shall be the purchaser's responsibility to determine which items are to be included in the order.

■ The standard designation as given in the relevant dimensional standard, the desired number of fittings, the type of DIN 50 049 materials testing certificate and, if necessary, any other relevant codes of practice shall be given in the order.

Continued on pages 2 to 11

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3 Materials

The materials to be used for the fittings covered here are given in table 2.

Where materials other than those given in table 2 are to be used, the specifications of this standard shall still apply.

The various forms of semi-finished products from which fittings are to be made are given as material groups, which are identified by a material designation and a code letter which is to be used for marking purposes.

4 Requirements

4.1 Manufacturing process

Manufacturing processes are specified in table 1, these being up to the manufacturer, who shall inform the purchaser of the process used, if so requested.

The manufacturer's works shall have appropriate personnel and suitable equipment and methods to carry out welding, hot or cold forming, machining operations and inspection and testing procedures in a satisfactory manner.

It shall be stated at the time of ordering whether certain fabrication processes, product forms or welding processes are not to be used.

Where fittings are manufactured by welding, the requirements specified in subclauses 4.1.1 to 4.1.3 and in DIN 8563 Parts 1 to 3 shall be complied with.

4.1.1 Welding

Welding shall be carried out so as to produce full penetration welds and to ensure that the fitting complies with the requirements specified here. Welding operations shall be inspected.

Fittings subject to internal pressure shall be welded so as to permit their use at full service pressure.

The quality class of the weld, in accordance with DIN 8563 Part 3, shall be agreed at the time of ordering.

4.1.2 Fusion welded fittings

Fusion welded fittings shall be welded on both sides, where the inner side is accessible.

Dressing of the weld is permitted, after which non-destructive testing shall be performed. The purchaser shall be permitted to request proof of the suitability of the dressing method used (cf. subclause 4.1.3).

4.1.3

The purchaser shall be permitted once to request proof of compliance with the requirements specified in subclause 4.1. The items to be included in the certificate to be issued, especially with regard to the testing agency, are subject to agreement between purchaser and manufacturer. The certificate shall be valid only for the materials, dimensions, welding processes and filler metals covered therein.

4.2 As delivered condition

4.2.1 Cold formed fittings

Heat treatment may be dispensed with in the case of cold formed fittings, provided the requirements for material characteristics specified in AD-Merkblatt HP 7/2 or HP 7/3 are complied with.

Where heat treatment (cf. subclause 4.2.2) of cold formed fittings is required, this shall be stated at the time of ordering.

4.2.2 Hot worked fittings

Fittings shall be supplied in one of the conditions specified in table 3, where no other specifications are made in the relevant materials standards. Heat treatment of fittings of material groups A to H and L to S shall be deemed satisfactory where such treatment ensures an adequately uniform microstructure. If this is the case, it shall be permitted to temper steels belonging to material groups J and K, as opposed to fully quenching and tempering them.

Table 1 - Manufacturing processes and semi-finished products 1) to be used for fittings

Type of fitting	Worked hot			Worked cold			Machined from solid product (up to size DN 50)
	Bent	Forge pressed 2)	Rolled, forged and machined	Bent	Forge pressed 2)	Cold shaped 2)
Bend	1, 2, 4, 5	1, 2, 3, 4, 5	-	1, 2, 4, 5	1, 2, 3, 4, 5	-	-
Tee	-	1, 2, 3, 4, 5	4, 5	-	1, 2, 3, 4, 5	-	-
Reducer	-	1, 2, 3, 4, 5	4, 5	-	1, 2, 3, 4, 5	1, 2, 3	5
Cap	-	1, 2, 3, 4, 5	4, 5	-	1, 2, 3, 4, 5	1, 2, 3	5

1) Key to code numbers:

1 - seamless tube

2 - welded tube (only material where the design stress of the weld can be utilized to 100 %)

3 - plate

4 - forging

5 - bar

2) This manufacturing process also permits welding operations to be carried out on the fittings.

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Table 2. Material symbols, standards to be complied with and service temperature ranges for semi-finished products

Table 2. Material symbols, standards to be complied with and service temperature ranges for semi-finished products

Code letter	Material designation	Steel grade	Material number	Semi-finished product 1)					Relevant standard	Service temperature range 2), in °C
				1	2	3	4	5
A	St 37.0	St 37.0	1.0254	x					DIN 1629	-10 to 300
		St 37.0	1.0254		x				DIN 1626
		RSt 37-2	1.0038			x	x	x	DIN 17 100
B	St 44.0	St 44.0	1.0256	x					DIN 1629	-10 to 300
		St 44.0	1.0256		x				DIN 1626
		St 44-2	1.0044			x	x	x	DIN 17 100
C	St 52.0	St 52.0	1.0421	x					DIN 1629	-10 to 300
		St 52.0	1.0421		x				DIN 1626
		St 52-3	1.0570			x	x	x	DIN 17 100
D	StE 290.7	StE 290.7	1.0484	x	x				DIN 17 172	-10 to 50
E	StE 360.7	StE 360.7	1.0582	x	x				DIN 17 172	-10 to 50
F	St 35.8 I	St 35.8 I	1.0305	x					DIN 17 175	-10 to 420
		St 37.8 I	1.0315		x				DIN 17 177
		H I	1.0345			x			DIN 17 155
		H II	1.0425			x			DIN 17 155
		C 22.8	1.0460				x	x	DIN 17 243
G	St 35.8 III	St 35.8 III	1.0305	x					DIN 17 175	-10 to 420
		St 37.8 III	1.0315		x				DIN 17 177
		H II	1.0425			x			DIN 17 155
		C 22.8	1.0460				x	x	DIN 17 243
H	15 Mo 3	15 Mo 3	1.5415	x					DIN 17 175	-10 to 530
					x				DIN 17 177
						x			DIN 17 155
							x	x	DIN 17 243
J	13 CrMo 44	13 CrMo 44	1.7335	x					DIN 17 175	-10 to 570
						x			DIN 17 155
							x	x	DIN 17 243
K	10 CrMo 910	10 CrMo 910	1.7380	x					DIN 17 175	-10 to 600
						x			DIN 17 155
							x	x	DIN 17 243
L	X 5 CrNi 18 10	X 5 CrNi 18 10	1.4301	x					DIN 17 458	-200 to 550 3)
					x				DIN 17 457
						x	x	x	DIN 17 440
M	X 2 CrNi 19 11	X 2 CrNi 19 11	1.4306	x					DIN 17 458	-200 5) to 550 3)
					x				DIN 17 457
						x	x	x	DIN 17 440

For *), 1), 3) and 5), see page 4.

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Table 2 (concluded).

Code letter	Material designation	Steel grade	Material number	Semi-finished product1)					Relevant standard	Service temperature range*), in °C
				1	2	3	4	5
N	X 6 CrNiTi 18 10	X 6 CrNiTi 18 10	1.4541	x 2)					DIN 17 458	– 2005) to 5503)
					x				DIN 17 457
						x	x	x	DIN 17 440
O	X 5 CrNiMo 17 12 2	X 5 CrNiMo 17 12 2	1.4401	x					DIN 17 458	– 200 to 5503)
					x				DIN 17 457
						x	x	x	DIN 17 440
P	X 2 CrNiMo 17 13 2	X 2 CrNiMo 17 13 2	1.4404	x					DIN 17 458	– 200 to 5503)
					x				DIN 17 457
						x	x	x	DIN 17 440
Q	X 6 CrNiMoTi 17 12 2	X 6 CrNiMoTi 17 12 2	1.4571	x 2)					DIN 17 458	– 2005) to 5503)
					x				DIN 17 457
						x	x	x	DIN 17 440
R	WStE 355	WStE 355	1.0565	x					DIN 17 179	– 20 to 400
					x				DIN 17 178
						x		x	DIN 17 102
							x		DIN 17 103
S	TStE 355	TStE 355	1.0566	x					DIN 17 179	– 60 to 504)
					x				DIN 17 178
						x		x	DIN 17 102
							x		DIN 17 103
T	TStE 285	TStE 285	1.0488	x					DIN 17 179	– 50 to 504)
					x				DIN 17 178
						x		x	DIN 17 102
							x		DIN 17 103
U	10 Ni 14	10 Ni 14	1.5637	x					DIN 17 173	– 105 to 504)
					x				DIN 17 174
						x	x	x	DIN 17 280

*) The values given are guideline values; those specified in the relevant materials standards shall be used in the actual design.

1) For 1), see table 1.

2) The information regarding pressure factors given in the relevant dimensional standards only applies where cold worked tubes are used as the semi-finished products. The purchaser and manufacturer shall agree whether hot worked tube may be used, since this material is of lower strength.

3) When tested for 100 000 h in accordance with DIN 50 914, it has been shown that the following materials, up to the temperatures given, are not susceptible to intercrystalline corrosion: group L or O (up to 300 °C), group M (up to 350 °C), and group N, P or Q (up to 400 °C).

4) It shall be permitted, for short periods of operation only, to exceed the service temperatures specified, since the low-temperature toughness of such materials may be adversely affected when used for prolonged periods at high temperatures.

5) Where service temperatures are between – 200 °C and – 270 °C, the impact energy, as measured on an ISO-V notch specimen at a test temperature of – 196 °C, shall be at least 40 J; this applies to wall thicknesses of 10 mm or more, and to bars and forgings not less than 15 mm in diameter.

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Table 3. Heat treatment conditions

As delivered condition	Material group	Code letter
Normalized or worked at normalizing temperature	A to H R to S	N
Quenched and tempered	J, K, U	V
Heat treated in solution	L to Q	L
Quenched and tempered or normalized	T	V, N

4.3 Chemical composition

The chemical composition of semi-finished products shall be as specified in the relevant materials standards.

It may be agreed to determine the chemical composition by product analysis, with specimens taken from either the semi-finished product or the fitting.

4.4 Mechanical properties

The material used shall have the mechanical properties specified in the relevant standard (cf. table 2). The impact strength of the weld metal shall be that of the parent metal, as measured on a test piece taken transverse to the direction of rolling.

4.5 Weldability

Information regarding weldability shall be obtained from the relevant standard (cf. table 2).

4.6 Surface condition

4.6.1 Fittings shall have a smooth inner and outer surface consistent with the manufacturing process used.

4.6.2 Slight irregularities in the surface (e.g. depressions, raised areas or shallow grooves) resulting from the manufacturing process used are permitted, provided the wall thickness is maintained within the tolerances specified.

4.6.3 Proper removal of shallow surface defects using appropriate means is permitted, provided the remaining wall thickness is maintained within the tolerances specified. The purchaser's consent shall be required for the dressing of welds.

4.6.4 Any further requirements on the surface finish shall be the subject of agreement.

4.7 Dimensions and tolerances

4.7.1 Dimensions

Fittings shall have the dimensions specified in the relevant dimensional standard.

4.7.2 Tolerances

4.7.2.1 Fittings shall be manufactured to the tolerances specified in the relevant dimensional standard.

4.7.2.2 The limit deviations for the outer diameter of the fitting ends are specified in table 4 (taken from DIN 1629). The upper limit deviation for wall thickness at the fitting end (dimensions s, s₁ and s₂) shall be equal to 15 % of the nominal wall thickness for all nominal sizes.

4.7.2.3 To ensure that flow is not obstructed, the inner diameter of fittings (except for caps) shall be at least 80 %, or 70 % in the case of tees, of the theoretical inner diameter of the pipe to be welded on. These values account for the upper limit deviations of wall thicknesses s₃, s₄, s₁ and s_u.

The theoretical inner diameter of the connecting pipe shall be calculated from d_a minus twice the nominal wall thickness.

4.7.2.4 The tolerances on circularity at the fitting end(s) shall be as specified in table 4 (taken from DIN 1626), that for elbows and bends being 4 % along the length of the fitting.

The out-of-roundness, R, as a percentage, shall be calculated from the following formula:

R = 200 · (d_{a max} − d_{a min}) / (d_{a max} + d_{a min}) (1)

where d_{a max} is the greatest outer diameter, and d_{a min} is the smallest outer diameter, measured in one plane.

4.7.2.5 Fittings shall be produced to form tolerance Q as specified in table 5 (cf. figures 1 to 7 for notation), measurements being made with the fittings placed against two surfaces normal to each other. Q shall not be exceeded at any point about the circumference of the fitting. Where Q is checked, the other fitting dimensions shall also be checked for compliance with the relevant dimensional standards. The subscripts given along with Q in figures 1 to 7 denote the dimension in the relevant dimensional standard to which Q refers.

Table 4. Limit deviations for outer diameter and circularity tolerance

Outer diameter, da, in mm	Limit deviations for outer diameter		Tolerance on circularity
		Subject to agreement.
≤ 100	± 1 % da (with a maximum of ± 0,5 mm)	± 0,4 mm	Within the specified tolerance on diameter.
100 < da ≤ 200	± 1 % da	± 0,5 % da
> 200	± 1 % da	± 0,6 % da	2 %

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4.7.3 Waviness

It shall be permitted for elbows and bends to exhibit shallow waves as illustrated in figure 8, provided that the mean wave height, h_m, does not exceed 3 % of d_a1 (cf. equation 2):

h_m = (d_a2 + d_a4) / 2 − d_a3 (2)

where

L is greater than or equal to 15 · h_m (3)

Figure 8.

Table 5. Tolerance Q

	Tolerance Q
Standard design	1 % of dimension (with a maximum of 1 mm)
Subject to agreement.	0,5 % of dimension (with a maximum of 0,5 mm)

4.7.4 Design of welding ends

The standard design of welding ends shall be so as to produce the following groove shapes (given as a function of the wall thickness ordered):

up to 3 mm: DIN 2559-1 groove shape;
over 3 mm up to 16 mm: DIN 2559-22 groove shape;
over 16 mm: DIN 2559-3 groove shape.

Other groove shapes shall be the subject of agreement.

5 Testing and materials testing certificates

5.1 General

Fittings complying with this standard may be supplied along with one of the following DIN 50 049 materials testing certificates:

a) certificate DIN 50 049-2.2 (test report);
b) certificate DIN 50 049-3.1 A (inspection certificate A);
c) certificate DIN 50 049-3.1 B (inspection certificate B);
d) certificate DIN 50 049-3.1 C (inspection certificate C).

The type of certificate and, in the case of third-party acceptance inspection, the inspection agency shall be stated at the time of ordering.

5.2 Test site

Testing of fittings shall be conducted at the manufacturer's works.

5.3 Scope of testing

5.3.1 Where fittings are to be supplied along with a DIN 50 049 test report, this shall give the values of yield strength, tensile strength and elongation after fracture and, if

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