Views: 4 Author: Site Editor Publish Time: 2025-01-16 Origin: Site
EN 1092-1 weld neck flange is a type of flange that is connected to pipes or other equipment by welding. EN 1092-1 is the European standard document for flanges and their fittings. The weld neck flange section specifies the design, dimensions, materials, marking and other requirements of butt-weld flanges, aiming to ensure the interchangeability and quality stability of weld neck flanges produced by different manufacturers in the European market.
Table of Content
→ EN 1092-1 Weld Neck Flange Specification
→ What is EN 1092-1 equivalent ASME?
→ What is the difference between EN1092-1 and EN1092-2?
→ What is the difference between ASME and EN standards?
→ Dimensions of Weld Neck Flange Type11 PN16 dimension
→ What are the disadvantages of a weld neck flange?
A weld neck flange (also known as a high-hub flange and tapered hub flange) is a type of flange. There are two designs. The regular type is used with pipes. The long type is unsuitable for pipes and is used in process plant.The weld neck flange comprises of a round fitting that extends beyond the rim of the circumference. These flanges, typically manufactured from forging, are actually welded to pipes.
EN 1092-1 Weld Neck Flange Specification
Standard | EN 1092-1 European Standard |
Manufacturing Process | Hot Forging / Steel Casting / Hot Rolled / Plate Machining |
Outer Diameter | DN 15 to DN 4000 |
Pressure Class | PN 2.5, PN 6, PN 8, PN 10, PN 16, PN 25, PN 40, PN 63, PN 100 etc |
Flanges Facing | Type Flat Face (FF), Type B Raised Face (RF), Type C Tongue, Type D Groove, Type E Spigot, Type F Recess, Type G O-ring Spigot, Type H O-ring Groove, |
EN 1092-1 Standard Scope
This European Standard for a single series of flanges specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 400 and nominal sizes from DN 10 to DN 4000.
This European Standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/ temperature ratings and approximate flange masses.
For the purpose of this European Standard, “flanges” include also lapped ends and collars.
This European Standard applies to flanges manufactured in accordance with the methods described in Table 1.
Non-gasketed pipe joints are outside the scope of this European Standard.
Bolting
Flanges shall be suitable for use with the number and size of bolting as specified in Table 10 to Table 21. The bolting shall be chosen by the equipment manufacturer according to the pressure, temperature, flange material and gasket so that the flanged joint remains tight under the expected operating conditions. For selection of bolting, see EN 1515-4, for combination of the materials of flanges and bolting see EN 1515-2, for information.
Gaskets
The various gasket types, dimensions, design characteristics and materials used are not within the scope of this European Standard. Dimensions of gaskets are given in the EN 1514 series.
Terms and definitions
For the purposes of this document, the following terms and definitions apply.
DN
Alphanumeric designation of size for components of a pipework system, which is used for reference purposes and which comprises the letters DN followed by a dimensionless whole number that is indirectly related to the physical size, in millimetres, of the bore or outside diameter of the end connections.
Note 1 to entry: The number following the letters DN does not represent a measurable value and should not be used for calculation purposes except where specified in the relevant standard.
Note 2 to entry: In those standards which use the DN designation system, any relationship between DN and component dimensions should be given, e.g. DN/OD or DN/ID.
[SOURCE: EN ISO 6708:1995, 2.1]
PN
Alphanumeric designation which is used for reference purposes related to a combination of mechanical and dimensional characteristics of a component of a pipework system and which comprises the letters PN followed by a dimensionless number.
Note 1 to entry: The number following the letters PN does not represent a measurable value and should not be used for calculation purposes except where specified in the relevant standard.
Note 2 to entry: The designation PN is not meaningful unless it is related to the relevant component standard number.
Note 3 to entry: The maximum allowable pressure of a pipework component depends on the PN number, the material and the design of the component, its maximum allowable temperature, etc. The relevant European Component standards include tables of specified pressure/temperature ratings or, in minimum, include rules how to determine pressure/temperature ratings.
Note 4 to entry: It is intended that all components with the same PN and DN designations have the same mating dimensions for compatible flange types.
[SOURCE: EN 1333:2006, 2.1]
What is EN 1092-1 equivalent ASME?
The Flange EN 1092-1 RF was developed as the standard for DIN-based flanges. This flange is widely used in industries such as oil, gas, mining, and commercial industries, and is now considered equivalent to ASME flanging in ASME B16. 5.
Both are aimed at standardizing the parameters and requirements of flanges and related connectors, aiming to ensure that flanges can safely and reliably achieve connection functions in pipeline systems. Whether it is following the EN 1092-1 standard in Europe or the ASME B16.5 standard in the United States and related regions, they are committed to ensuring the stable operation of pipeline systems under different working conditions and preventing safety accidents such as leakage and rupture caused by flange problems.
What is the difference between EN1092-1 and EN1092-2?
EN 1092 is a series of standard specifications for flanges and their joints – circular flanges for pipes, valves, fittings and accessories, PN designated. These directive codes are released by EU’s standardization organization CEN and they are mainly derived from relative British and German flange standards (BS 4504 & DIN, etc). EN 1092 covers four parts: Part 1(EN 1092-1): steel flanges; Part 2(EN 1092-2): cast iron flanges; Part 3(EN 1092-3): copper alloy flanges; Part 4(EN 1092-4): aluminium alloy flanges.
Scope of application
EN 1092-1: This standard is mainly applicable to various types of steel flanges such as weld neck flanges, flat welding flanges, blind flanges, etc. used in industrial pipeline systems. The application scenarios cover many industrial fields such as petroleum, chemical industry, and electricity. It aims to standardize the design, manufacturing, size and quality requirements of these flanges under different working conditions to ensure their safety and reliability in pipeline connections.
EN 1092-2: Mainly for cast iron and cast steel flanges and their connectors, focusing on the pipeline connections of these materials in general industrial and construction applications, such as in some building water supply and drainage systems with relatively low pressure requirements and relatively weak corrosion, and general industrial fluid transportation.
What is the difference between ASME and EN standards?
Standard-making organizations and applicable regions
EN: Developed by relevant European organizations such as the European Committee for Standardization (CEN), applicable to Europe and some countries and regions that adopt the European standard system. In the European market, following EN standards is an important basis for products to enter the market and ensure compatibility and safety.
ASME: Developed by the American Society of Mechanical Engineers, it is mainly applicable to the United States and some countries and regions that recognize the American standard system. In the United States and related trade areas, ASME standards are authoritative and dominant.
Dimension system
EN: In EN 1092-1 weld neck flange standards, nominal pressure (PN) and nominal diameter (DN) are used to indicate size specifications. For example, the nominal pressure ranges from PN 2.5 to PN 400, and the nominal diameter covers a range from smaller sizes to larger specifications such as DN 2000.
ASME: Use pound class (Class) and nominal pipe diameter (NPS) to determine the size. There are multiple levels of pound classes such as Class 150 and Class 300, and the nominal pipe diameter ranges from NPS 1/2 to NPS 24, etc.
NOTE 1
The transition from the edge of the raised face to the flange face can be by radius or chamfer for types B, D, F and G only (see 5.7.1).
NOTE 2
B1 and B2 are raised face (type B) for different applications (see 5.7.2.2, 5.7.2.3 and Table 2).
NOTE 3
For the dimensions of flange facings, see Figure 4 and Table 8.
Flanges Types | |
Type 01 | Plate Flange for welding, |
Type 02 | Loose Plate Flange with Weld-on Plate Collar or for Lapped Pipe End, |
Type 04 | Loose Plate Flange with weld-neck collar, |
Type 05 | Blind Flange, |
Type 11 | Weld-neck Flange, |
Type 12 | Hubbed Slip-on Flange for welding, |
Type 13 | Hubbed Threaded Flange, |
Type 34 | Weld-neck collar Flange, |
Type 35 | Weldring neck Flange, |
Type 36 | Pressed collar with long neck Flange, |
Type 37 | Pressed collar Flange, |
Dimensions of EN 1092-1 Weld Neck Flange Type11 PN16
The specifications of butt welding flanges are mainly applicable to sizes ranging from DN10 to DN4000. The production standard is EN 1092-1. The following figure shows the sizes DN10-DN350 under some PN16.
Table 13 — Dimensions of PN 16 flanges | |||||||||||||||||||||||||||||||
Dimensions in millimetres | |||||||||||||||||||||||||||||||
DN | Mating dimensions | Outside diameter of neck | Bore diameters | Flange thickness | Chamfer | Collar thickness | Centre portion | Length | Neck diameters | Corner radii | Wall thickness (see 5.6.1) | ||||||||||||||||||||
Outside diameter | Diameter of bolt circle | Diameter of bolt hole | Bolting | ||||||||||||||||||||||||||||
D | K | L | Number | Size | A | B1 | B2 | B3 | C1 | C2 | C3 | C4 | E | F | Gmax | H1 | H2 | H3 | H4 | H5 | N1 | N2 | N3 | R1 | S | ||||||
Flange type | |||||||||||||||||||||||||||||||
01, 02, 04, 05, 11, 12, 13, 21 | 11 21 a 34 d 35 - 37 | 01 12 32 | 02 | 04 | 01 02 04 | 11 12 13 | 21 | 05 | 02 04 | 32 34 d | 35 | 36 | 37 | 05 | 12 13 | 11 34 c,d | 11 34 c,d | 35 | 36 | 37 | 11 34 c, d | 12 13 | 21 | 11 12 13 21, 34d | 34 d | 11, 35 to 37 | |||||
10 | 90 | 60 | 14 | 4 | M12 | 172 | 180 | 21 | 31 | 14 | 16 | 16 | 16 | 3 | 12 | 5 | 2 | 25 | 22 | 35 | 6 | 35 | 35 | 7 | 28 | 30 | 28 | 4 | 18 | See Annex A | |
15 | 95 | 65 | 14 | 4 | M12 | 213 | 220 | 25 | 35 | 14 | 16 | 16 | 16 | 3 | 12 | 5 | 2 | 25 | 22 | 38 | 6 | 38 | 38 | 7 | 32 | 35 | 32 | 4 | 20 | ||
20 | 105 | 75 | 14 | 4 | M12 | 269 | 275 | 31 | 42 | 16 | 18 | 18 | 18 | 4 | 14 | 6 | 25 | 3 | 26 | 40 | 6 | 40 | 40 | 8 | 40 | 45 | 40 | 4 | 23 | ||
25 | 115 | 85 | 14 | 4 | M12 | 337 | 345 | 38 | 49 | 16 | 18 | 18 | 18 | 4 | 14 | 7 | 25 | 3 | 28 | 40 | 6 | 40 | 40 | 10 | 46 | 52 | 50 | 4 | 26 | ||
32 | 140 | 100 | 18 | 4 | M16 | 424 | 435 | 47 | 59 | 18 | 18 | 18 | 18 | 5 | 14 | 8 | 3 | 3 | 30 | 42 | 6 | 42 | 42 | 12 | 56 | 60 | 60 | 6 | 26 | ||
40 | 150 | 110 | 18 | 4 | M16 | 483 | 495 | 53 | 67 | 18 | 18 | 18 | 18 | 5 | 14 | 8 | 3 | 3 | 32 | 45 | 7 | 45 | 45 | 15 | 64 | 70 | 70 | 6 | 26 | ||
50 | 165 | 125 | 18 | 4 | M16 | 603 | 615 | 65 | 77 | 20 | 18 | 18 | 18 | 5 | 16 | 8 | 3 | 3 | 28 | 45 | 8 | 45 | 45 | 20 | 74 | 84 | 84 | 6 | 29 | ||
65 | 185 | 145 | 18 | 8b | M16 | 761 | 775 | 81 | 96 | 20 | 18 | 18 | 18 | 6 | 16 | 8 | 3 | 3 | 55 | 32 | 45 | 10 | 45 | 45 | 20 | 92 | 104 | 104 | 6 | 29 | |
80 | 200 | 160 | 18 | 8 | M16 | 889 | 905 | 94 | 108 | 20 | 20 | 20 | 20 | 6 | 16 | 10 | 3 | 3 | 70 | 34 | 50 | 10 | 50 | 50 | 25 | 105 | 118 | 120 | 6 | 32 | |
100 | 220 | 180 | 18 | 8 | M16 | 1,143 | 1,160 | 120 | 134 | 22 | 20 | 20 | 20 | 6 | 18 | 10 | 4 | 4 | 90 | 40 | 52 | 12 | 52 | 52 | 25 | 131 | 140 | 140 | 8 | 36 | |
125 | 250 | 210 | 18 | 8 | M16 | 1,397 | 1,415 | 145 | 162 | 22 | 22 | 22 | 22 | 6 | 18 | 10 | 4 | 4 | 115 | 44 | 55 | 12 | 55 | 55 | 25 | 156 | 168 | 170 | 8 | 40 | |
150 | 285 | 240 | 22 | 8 | M20 | 1,683 | 1,705 | 174 | 188 | 24 | 22 | 22 | 22 | 6 | 20 | 10 | 5 | 5 | 140 | 44 | 55 | 12 | 55 | 55 | 25 | 184 | 195 | 190 | 10 | 45 | |
200 | 340 | 295 | 22 | 12 | M20 | 2,191 | 2,215 | 226 | 240 | 26 | 24 | 24 | 24 | 6 | 20 | 11 | 6 | 6 | 190 | 44 | 62 | 16 | 62 | 62 | 30 | 235 | 246 | 246 | 10 | 63 | |
250 | 405 | 355 | 26 | 12 | M24 | 2,730 | 2,765 | 281 | 294 | 29 | 26 | 26 | 26 | 8 | 22 | 12 | 10 | 235 | 46 | 70 | 16 | 70 | 68 | 292 | 298 | 296 | 12 | 63 | |||
300 | 460 | 410 | 26 | 12 | M24 | 3,239 | 3,275 | 333 | 348 | 32 | 28 | 28 | 28 | 8 | 24 | 14 | 10 | 285 | 46 | 78 | 16 | 78 | 68 | 344 | 350 | 350 | 12 | 71 | |||
350 | 520 | 470 | 26 | 16 | M24 | 3,556 | 3,595 | 365 | 400 | 35 | 30 | 30 | 30 | 8 | 26 | 18 | 10 | 330 | 57 | 82 | 16 | 82 | 68 | 390 | 400 | 410 | 12 | 80 |
What are the disadvantages of a weld neck flange?
Good stress distribution:
When the EN 1092-1 weld neck flange is welded to the pipeline, due to the structural characteristics of its butt weld, the pressure and other loads in the pipeline can be evenly distributed throughout the entire connection. Compared with some other connection methods, the stress concentration phenomenon of the weld neck flange is significantly reduced, which greatly improves the safety and reliability of the pipeline system under harsh working conditions such as high pressure and high temperature.
Reduced friction and interference:
The welded connection will not interfere with the flow of the fluid. With the reduced friction, the fluid will not develop turbulence allowing for less vibration and a smoother flow. Less turbulence will also allow for a quieter operation.
Durable connection:
Stress on the inside is transferred to the neck of the flange taking the pressure off the pipe allowing for a more permanent connection.
Leakage prevention:
In most applications using the weld neck flanges, the weld is made inside and outside of the flange. This will provide a connection that is more leak proof.
Ease of installation:
When using the butt weld flanges it is easier to determine pipe length applications because the calculations do not have to account for the space taken up by threads on bolt-on applications. Slip-on flanges also require calculation using the insertion amount.
You can get an offer for products in below material forms:
- Pipe and Tube (EN 10216-5, ASTM A213, ASTM A249, A312, A790,)
- Forged Fitting and Flange (ASTM A182 , ASTM A105,ASTM B564 )
- Butt Weld Fittings (ASTM A234, ASTM A403,ASTM A815)
- Round bar , Billet (ASTM A276, ASTM A479)
- Plate, Sheet, Strip(ASTM A240, EN 10028-7, A480)
- Bolting, Nuts(ASTM A193, A194, A320)