Content Summary

 

 STEEL FLANGES FOR PIPELINES

 FLANGES FOR PIPELINES

Flanges are generally used to connect one pipe to another pipe or to connect a pipe to a valve, avoiding direct welded connections among such items which would require longer execution time and generate higher costs. A flanged joint, or flanged pipe connection, is made by bolting together two flanges (main flange and companion flange) and sealing such connection by means of metallic gasket (ring joint gasket), a semi metallic gasket (spiral wound gasket and jacketed gaskets) or non metallic gaskets (flat cut gaskets, asbestos free). The correct installation of flanges and gaskets is key to ensure leak free piping system. Flanges also allow easy access to a pipeline to clean, inspect or implement needed modifications or retrofit the pipeline.

 FLANGES AND PIPELINE PRESSURE / TEMPERATURE

ASME and API pipeline flanges can withstand different pressures at different temperatures of the fluid flowing in the conduit. As the working temperature increases, the pressure rating of the flange decreases (of course the pressure rating also depends on material of the flange itself, the higher the material grade, the better the pressure rating at increasing temperatures).

Pipelines with relatively high pressures and temperatures generally require butt weld connections (welding neck, ring joint flange connection types) instead of fillet welds or threaded connections (slip on flanges, socket weld flanges and threaded flanges), as under such circumstances the expansion, contraction and bending of the pipeline may crack the fillet welds and impact the efficiency of the flanged joint (same consideration is applicable to flanged connections for pumps, compressors and turbines, subject to intense vibration and mechanical stress). Butt weld connections may absorb the stress of the pipeline better as the tensions get more evenly distributed on the overall system, and the strength of the BW connection is in line with the strength of the base material (whereas in the case of threaded connections the stress gets concentrated in specific points that may crack in case of mechanical stress).

 FLANGES FACING

The term “flange facing” is connected to the shape of the contact surface that shall seal the connection. The ASME B16.5 and ASME B16.47 Norms contemplate different types of flanges facing such as the raised face (RF), the large male and female facings, the large and small tongue-and-groove facings and the ring joint facing which is designed for ring joint type metal gaskets (RTJ gaskets). RTJ, T&G and the male/ female faced flanges shall never be bolted together, since the contact surfaces of different types of gaskets do not match to each other and would not provide a leak proof seal. The optional flange facings are described and pictured below:

ASME flange facing

 RAISED FACE (RF FLANGE)

RF flange raised face

Raised face flanges (RF flanges) are widely used in process pipelines and are easy to recognize because the gasket surface is located above the bolting line of the flange. RF flanges are compatible with a wide range of gaskets, from the flat cut types (compressed sheets, asbestos free gaskets) to the metallic and semi-metallic types (jacketed gaskets and spiral wound gaskets). The main goal of RF flanges is to concentrate the pressure on a defined and relatively small area of the flange thus increasing the strength of the seal. The height of the raised surface depends on the rating of the flange and is defined by ASME B16.5 (for pressure classes 150 and 300, the height of raised face shall be approx. 1.6 mm (1/16 inch), while, for classes from 400 to 2500, the raised face height shall be approximately 6.4 mm (1/4 inch). The most common flange face finish for ASME B16.5 RF flanges is 125 to 250 micron Ra (3 to 6 micron Ra).

 FLAT FACE (FF FLANGE)

flat face flange

A flat face flange (FF flange) has a gasket surface that is at the same height of the bolting line of the flange. Such types of flanges shall never be bolted to RF flanges according to ASME B31.1.

 RING JOINT (RTJ)

ring joint flange

Ring Type Joint flanges (RTJ flanges) create a metal to metal seal between the connecting flanges. Such type of flange is used in high-pressure and high-temperature services (say above class 600). RTJ flanges faces have grooves on the face which can host steel-made ring gaskets. As two RTJ are bolted and tightened, the applied force compresses the steel joints and deforms them inside the groove to create a complete metal seal of the flange. It is, of course, obvious that the ring joint gasket material has to be softer than the flange material to allow the formation of a proper seal after tightening. Steel ring joint are manufactured with multiple profiles, the most typical ones are octagonal and oval (RTJ flange, type R) and are in accordance with the ASME B16.20. The octagonal cross section (RTJ flange, type R octagonal) has a better sealing strength and shall always be preferred; the oval section is an oldest type or RTJ R flange and can be used only on older types of grooved flanges (round). The bottom groove design instead accepts both cross profiles, octagonal and oval. Style R ring type joints seal pressures up to 6,250 psi by ASME B16.5 pressure ratings and up to 5,000 psi. Beside R type RTJ flanges, the market offers also RX and BX types of ring joint flanges.

 TONGUE & GROOVE (T&G)

tongue & groove flange

Two T&G flanges are conceived to be matched one to the other. Indeed, the raised ring (tongue) of one flange is designed to match the groove of the other flange. T&G facings are standardized in both large and small types. T&G facing differ from the male/female facing because the inside diameters of the T&G doesn’t extend into the flange base, thus retaining the gasket on its inner and outer diameter.

 MALE & FEMALE (M&F)

male & female flange

Male and female flanges (M&F flanges) are manufactured to be matched one to the other as well. Indeed, one flange face has an area extended beyond the normal flange face, i.e. the male, while the other flange has a matching depression machined on the facing surface, i.e. the female. The female face is 3/16'' deep, while the male face is 1/4-inch high, and both of them are smooth finished. The outer diameter of the female face retains the gasket.

 FLANGE FACE FINISH

flange finish types

STOCK FINISH
As the name suggests, the stock finish is the most widely used face finish because it is suitable for most service conditions. Once flanges are bolted, the gaskets get embedded into the face of the flange and creates a very tight seal.

SPIRAL SERRATED
This finish is a continuous or phonographic spiral groove, but it differs from the stock finish because the groove is typically generated using a 90°-degree tool that creates a "V" geometry with a 45° angled serration. A serrated finish, concentric or spiral, is required with 30 to 55 grooves per inch and a consequent roughness between 125 and 500 micro inches.

CONCENTRIC SERRATED
The concentric serrated finish shows concentric grooves. A 90° degree tool is used, and the serrations are spaced evenly across the face.

SMOOTH FINISH
Smooth finish flanges are used just for low pressure and or large diameter pipelines and primarily intended for application with solid metal or spiral wound gaskets.

 FLANGES TYPES

There are several types of flanges, the main ones are:

 WELDING NECK FLANGE and LONG WELDING NECK FLANGE

welding neck flange ASME

A welding neck flange (flange WN or WN flange or weld neck flange) has a long tapered hub that can be welded with a pipe or a fitting and is normally used in applications that involve high pressure and low or high temperatures. The schedule of the welding neck flange matches the schedule of the pipe or the fitting and the elements are welded together by a single full penetration V-shaped butt weld.

 SLIP ON FLANGE

slip on flange ASME

Slip-on flanges are connected with pipes or fittings by two fillet welds, inside and outside the flange. The lifetime of a slip on flange is 1/3 as compared to a welding neck flange, under the same fatigue conditions. While fittings can be welded directly on WN flanges, only pipes can be welded directly to slip on flanges.

 THREADED FLANGE

threaded flange ASME

Threaded flanges are connected to pipes using a threaded connection. Therefore, no welding is necessary (even if a seal weld may be applied in certain circumstances). Even if available in most sizes and pressure ratings, screwed flanges are used almost exclusively for smaller pipe sizes having a non-thin wall thickness.

 SOCKET WELD FLANGE

socket weld flange ASME

Socket weld flanges are connected to pipes using 1 fillet weld which is executed on the outer of the flange. Socket Weld Flanges are suited for small-size and high-pressure piping. Their static strength is equal to slip on flanges, but their fatigue strength is 50% greater than double-welded slip on flanges.

 LAP JOINT FLANGE

Lap joint flange

Lap joint flanges do not have a raised face and are used in conjunction with a lap joint stub end to generate a joint connection. Lap joint flanges are similar to the slip on type except for the radius at the crossing of the flange face and the bore to accommodate the flanged portion of the stub end. These flanges are intended to slip on the pipe and are not welded or fastened to it by other means. The pressure of bolts is passed to the gasket by the pressure of the flange against the back of the stub end. A Stub End always in always used in connection with a lap joint flange, that acts as a backing flange. This arrangement is used in low-pressure and non-critical applications and is a cheap method of flanging. In a stainless steel pipeline involving corrosion, for instance, a carbon steel flange can be applied, and such flange will not come into contact with the corrosive fluid. Stub Ends are available most pipe dimensions. Carbon steel stub ends dimensions, and dimensional tolerances are ruled by the ASME B.16.9 standard while light-weight corrosion resistant stub ends are in accordance with in MSS SP43.

 BLND FLANGE

blinf flange ASME

Blind Flanges do not have a bore and are used close off the ends of a pipeline or valves or pressure vessels. Blind flanges shall withstand high mechanical stress due to system pressure and bolting.

 ORIFICE FLANGE

orifice flange ASME

Orifice Flanges have orifice meters to measure the flow rate of fluids or gas in the pipeline. Orifice flanges are available in all standard sizes and ranges, and all common flange materials. Orifice flanges are available in the welding neck, slip on and threaded configuration and are typically supplied with two 1/2" NPT tapers on each flange. Orifice flanges have either a raised face or a ring joint type facing (RTJ). Dimensions and dimensional tolerances of orifice flanges are covered by ASME B16.36.

 SPECTABLE BLIND, SPADE, RING SPACER

spectable blind ASME

A Spectacle Blind is a steel plate which has two discs of a certain thickness, one has the shape of a solid plate and the other one is essentially a ring whose inside diameter equals the flange bore. Spectacle Blinds are used to open or close a pipeline for maintenance purposes. When the Spectable blind is in the open position, the fluid can flow in the pipeline; when the Spectable blind is in the closed position, by simply loosing the bolts and rotating the element, the fluid flow is interrupted. A spade equals to the solid ring of a spectable blind, while a ring spacer is similar to the ring disc of a spectable blind: spades and spacers are used in large size pipeline systems where a spectable blind would be too heavy to withstand for the flanged joint. The ASME B16.48 norm covers the pressure and temperature ratings, the materials, the dimensions and the dimensional tolerances, the marking and the testing for operating line blanks in sizes NPS 1/2 - NPS 24 for installation between ASME B16.5 flanges of classes 150, 300, 600, 900, 1500, and 2500. Spectacle Blinds, spades and ring spacers shall be made from a plate or forged piece approved for use by ASME B31.3 and manufactured in the same material grade used for the corresponding flanges and pipes.

 FLANGES DIMENSIONS AND WEIGHTS

FLANGE NPS:1/2'' - 60’’ (larger sizes are however possible)

 FLANGE CLASS / FLANGES RATING:

  • ASTM flange, ANSI flange, ASME flange: 150, 300, 400, 600, 900, 1500, 2500 (pounds, class, rating, lbs).
  • JIS B2220 flange, KS1503 flange: 5K, 10K, 16K, 20K, 30K
  • DIN flange, UNI flange, EN1092-1 flange, BS 4504 flange, GOST12820/12821-80 flange: PN6, PN10, PN16, PN25, PN40, PN63, PN100
  • SANS/SABS 1123 flange (South Africa): Class 600/3, 1000/3, 1600/3, 2500/3, 4000/3

Given a certain NPS, as the rating increases the weight and the size of the flange also increases to withstand higher process conditions in terms of pressures and temperature.

Example of the flange size increase in connection with the flange class:

Class of flanges

 ASME B16.5 FLANGES TOLERANCES

ASME B16.5 FLANGES TOLERANCES

(Source Trouvay & Cauvin - Piping equipment "Blue book")

 NORMS

The norms that are relevant to the manufacturing of flanges for pipelines are:

  • ASME B16.5: all flanges, 1/2" - 24"This Standard covers the pressure-temperature ratings, materials, dimensions, dimensional tolerances, marking, testing, and methods of designating openings for pipe flanges and flanged fittings. ASME B16.5 focuses on flanges and flanged fittings manufactured out of cast or forged materials, and blind flanges and specific reducing flanges from cast, forged, or plate materials. The standard also foresees requirements and recommendations related to flange bolting, flange gaskets, and flange joints.
  • ASME B 16.47-Series A / B: blind and welding neck flanges 26’’-60’’This Standard covers the dimensional tolerances, pressure-temperature ratings, materials, dimensions, testing and marking for pipe flanges in sizes between NPS 26” and NPS 60” and in Classes 75 to 900. Flanges may be manufactured out of cast and forged materials, or plate (in the sole case of blind flanges). The standard also foresees requirements and recommendations related to bolting and gaskets. Note: Most of the MSS-SP44 have been included in ASME B16.47 Series A specifications, whereas the API 605 specifications have been incorporated into ASME B16.47 series B. They have also added Blinds to these two specs.
  • ASME B16.36: orifice flangesThis Standard covers flanges (similar to those covered in ASME B16.5) that have orifice pressure differential connections. The coverage of ASME B16.36 is limited to the following: (a) Welding Neck Flanges Classes 300-2500 (b) slip-on and threaded Class 300.
  • ASME B16.48: Spectable blinds, spades, spacer ringsThis norm covers the dimensions, marking, pressure-temperature ratings, materials, dimensional tolerances and testing for line blanks in sizes between NPS 1/2 and NPS 24 for installation between ASME B16.5 flanges in the classes from 150 to 2500.
  • BS 3293: slip on, welding neck flanges 26’’-60’’
  • API 6A
  • EN 1092-1: Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories
  • DIN/UNI: various
  • JIS B2220: welded pipe flanges
  • KS B1503: welded pipe flanges
  • MSS SP-9: standard for spot facing flanges
  • MSS SP-44: standard for steel pipeline flanges
  • MSS SP-60: standard for connecting flange joint
  • GOST 12820-80, 12821-80: Russian pipe flanges standard for flat and welding neck type

 NUMBER AND SIZE OF BOLTS / GASKETS FOR FLANGED JOINTS

# Bolting FF NOMINAL PIPE SIZE
1/2 3/4 1 2 3 4 5 6 8 10 12 14 16 18 20 24
Class 150 Number   4 4 4 4 4 4 4 4 8 8 8 8 8 12 12 12 16 16 20 20
Diameter   ½ ½ ½ ½ ½ 5/8 5/8 5/8 5/8 5/8 ¾ ¾ ¾ 7/8 7/8 1 1 1 1/8 1 1/8
Length of Stud Bolts 1/16” RF 4 5 1/4 5 1/4
RTJ     3 4 4 4 4 5
Lth Mach Bolts 1/16” RF 2 2 3 3 3 3 3 1/4 3 1/4 4 4 5 6
Ring No.       R15 R17 R19 R22 R25 R29 R33 R36 R40 R43 R48 R52 R56 R59 R64 R68 R72 R76
Class 300 Number   4 4 4 4 4 8 8 8 8 8 8 12 12 16 16 20 20 24 24 24
Diameter   ½ 5/8 5/8 5/8 ¾ 5/8 ¾ ¾ ¾ ¾ ¾ ¾ 7/8 1 1 1/8 1 1/8
Length of Stud Bolts 1/16” RF 3 3 4 4 3/4 7 8 9
RTJ 3 4 4 4 1/2 5 5 6 8 10
Lth Mach Bolts 1/16” RF 3 3 8
Ring No.   R11 R15 R16 R18 R20 R23 R26 R31 R34 R37 R41 R45 R49 R53 R57 R61 R65 R69 R73 R77
Class 400 Number   4 4 4 4 4 8 8 8 8 8 8 12 12 16 16 20 20 24 24 24
Diameter   ½ 5/8 5/8 5/8 ¾ 5/8 ¾ ¾ 7/8 7/8 7/8 7/8 1 1 1/8 1 3/8 1 3/8
Length of Stud Bolts ¼” RF 3 5 6 8 9 10½
M&F T&G 3 1/2 4 4 8 10¼
RTJ 3 5 6 7 1/2 8 9 11
Ring No.   R11 R13 R16 R18 R20 R23 R26 R31 R34 R37 R41 R45 R49 R53 R57 R61 R65 R69 R73 R77
Class 600 Number   4 4 4 4 4 8 8 8 8 8 8 12 12 16 20 20 20 20 24 24
Diameter   ½ 5/8 5/8 5/8 ¾ 5/8 ¾ ¾ 7/8 7/8 1 1 1 1/8 1 3/8 1 5/8 15/8 1 7/8
Length of Stud Bolts ¼” RF 3 5 10 10¾ 11¼ 13
M&F T&G 4 4 9 10½ 11 12¾
RTJ 3 5 10 10¾ 11½ 13¼
Ring No.   R11 R13 R16 R18 R20 R23 R26 R31 R34 R37 R41 R45 R49 R53 R57 R61 R65 R69 R73 R77
Class 900 Number   4 4 4 4 4 8 8 8   8 8 12 12 16 20 20 20 20 20 20
Diameter   ¾ ¾ 7/8 7/8 1 7/8 1 7/8   1 1/8 1 1/8 1 3/8 1 3/8 1 3/8 1 5/8 1 7/8 2
Length of Stud Bolts ¼” RF 5 5   10 10¾ 11¼ 12¾ 13¾ 17¼
M&F T&G 4 6   9 10½ 11 12½ 13½ 17
RTJ 5 5   10 11 11½ 13¼ 14¼ 18
Ring No.   R12 R14 R16 R18 R20 R24 R27 R31   R37 R41 R45 R49 R53 R57 R62 R66 R70 R74 R78
Class 1500 Number   4 4 4 4 4 8 8 8   8 8 12 12 12 16 16 16 16 16 16
Diameter   ¾ ¾ 7/8 7/8 1 7/8 1 1 1/8   1 3/8 1 5/8 1 7/8 2 3
Length of Stud Bolts ¼” RF 5 5 7   10 1/4 11½ 13 1/4 14¾ 16 17½ 19½ 21¼ 24¼
M&F T&G 4 6   10 11¼ 13 14½ 15¾ 17¼ 19¼ 21 24
RTJ 5 5 7   10½ 12¾ 13½ 15¼ 16¾ 18½ 20¾ 22¼ 25½
Ring No.   R12 R14 R16 R18 R20 R24 R27 R35   R39 R44 R46 R50 R54 R58 R63 R67 R71 R75 R79
Class 2500 Number   4 4 4 4 4 8 8 8   8 8 8 12 12 12          
Diameter   ¾ ¾ 7/8 1 1 1/8 1 1 1/8   2 2          
Length of Stud Bolts ¼” RF 5 6 7   10 11¾ 13½ 15 19¼ 21¼          
M&F T&G   11½ 13¼ 14¾ 19 21          
RTJ 5 6 7 8 9   10¼ 12¼ 14 15½ 20 22          
Ring No.   R13 R16 R18 R21 R23 R26 R28 R32   R38 R42 R47 R51 R55 R60          

 FLANGES ISOMETRICS

FLANGES ISOMETRICS FLANGES WEIGHTS AND DIMENSIONS FLANGES WEIGHTS AND DIMENSIONS

 FLANGES MATERIAL GRADES

Flanges are available in most forged material grades such as carbon steel (high and low temperature), austenitic and martensitic stainless steel, cast iron, aluminum, brass, bronze, plastic, etc. Under specific circumstances, and similarly to pipes and butt weld fittings, flanges may be lined internally with layers of special material and cope with specific process requirements that the bare flanges would not meet.

The material grade of the flange matches with the material grade of the pipes. Flanges material grades are generally according to ASTM; the most common material grades for flanges are:

CARBON STEEL / ALLOY STEEL FLANGE STAINLESS STEEL / NICKEL ALLOY STEEL FLANGE
ASTM A105, ASTM A266 Gr. 2, ASTM A350 Gr. LF1, ASTM A350 Gr. LF2, ASTM A350 Gr. LF3, ASTM A694 Gr. F42, ASTM A694 Gr. F52, ASTM A694 Gr. F56, ASTM A694 Gr. F60, ASTM A694 Gr. F65, ASTM A182 Gr. F1, ASTM A182 Gr. F2, ASTM A182 Gr. F5, ASTM A182 Gr. F9, ASTM A182 Gr. F11 Cl. 2, ASTM A182 Gr. F12 Cl. 2, ASTM A182 Gr. F22 Cl. 3, ASTM A182 Gr. F91 ASTM A182 F304, ASTM A182 F304L, ASTM A182 F304H, ASTM A182 F310, ASTM A182 F316, ASTM A182 F316L, ASTM A182 F316H, ASTM A182 F321, ASTM A182 F347, ASTM A182 Gr. F51 (duplex steel flanges), ASTM A182 Gr. F53 (Superduplex), ASTM A182 Gr. F55 (Superduplex steel flanges), ASTM A182 TP904L, ASTM B166 UNS NO6600 (Inconel 600 flanges), ASTM B564 UNS N06625 (Inconel® 625), ASTM B564 UNS N08825 (Incoloy® 825), ASTM B425 UNS-NO8800 (Incoloy® 800), ASTM B160 UNS N0200 (Nickel 200), ASTM B564 UNS N04400 (Monel® 400), ASTM B564 UNS N10276 (Hastelloy® C-276), ASTM B381 Gr. 2 (Titanium)

 PIPING ASTM GRADES (PIPES, BUTT WELD FITTINGS, FORGED FITTINGS, VALVES, BOLTS)

MATERIAL PIPES BW FITTINGS FORGINGS VALVES BOLTING SETS
Carbon Steel A106 Gr A A234 Gr WPA A105 A216 Gr WCB A193 Gr B7
A194 Gr 2H
A106 Gr B A234 Gr WPB A105 A216 Gr WCB
A106 Gr C A234 Gr WPC A105 A216 Gr WCB
Carbon Steel
Alloy
High-Temp
A335 Gr P1 A234 Gr WP1 A182 Gr F1 A217 Gr WC1 A193 Gr B7
A194 Gr 2H
A335 Gr P11 A234 Gr WP11 A182 Gr F11 A217 Gr WC6
A335 Gr P12 A234 Gr WP12 A182 Gr F12 A217 Gr WC6
A335 Gr P22 A234 Gr WP22 A182 Gr F22 A217 Gr WC9
A335 Gr P5 A234 Gr WP5 A182 Gr F5 A217 Gr C5
A335 Gr P9 A234 Gr WP9 A182 Gr F9 A217 Gr C12
Carbon Steel
Alloy
Low-Temp
A333 Gr 6 A420 Gr WPL6 A350 Gr LF2 A352 Gr LCB A320 Gr L7
A194 Gr 7
A333 Gr 3 A420 Gr WPL3 A350 Gr LF3 A352 Gr LC3
Austenitic
Stainless
Steel
A312 Gr TP304 A403 Gr WP304 A182 Gr F304 A182 Gr F304 A193 Gr B8
A194 Gr 8
A312 Gr TP316 A403 Gr WP316 A182 Gr F316 A182 Gr F316
A312 Gr TP321 A403 Gr WP321 A182 Gr F321 A182 Gr F321
A312 Gr TP347 A403 Gr WP347 A182 Gr F347 A182 Gr F347
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 PRESSURE AND TEMPERATURE RATINGS FOR ASTM A105, A350 LF2-LF3-LF6 (working pressure by Class, in bar)

TEMP. C 150# 300# 400# 600# 900# 1500# 2500#
-29 to 38 19.6 51.1 68.1 102.1 153.2 255.3 425.5
50 19.2 50.1 66.8 100.2 150.4 250.6 417.7
100 17.7 46.6 62.1 93.2 139.8 233 388.3
150 15.8 45.1 60.1 90.2 135.2 225.4 375.6
200 13.8 43.8 58.4 87.6 131.4 219 365
250 12.1 41.9 55.9 83.9 125.8 209.7 349.5
300 10.2 39.8 53.1 79.6 119.5 199.1 331.8
325 9.3 38.7 51.6 77.4 116.1 193.6 322.6
350 8.4 37.6 50.1 75.1 112.7 187.8 313
375 7.4 36.4 48.5 72.7 109.1 181.8 303.1
400 6.5 34.7 46.3 69.4 104.2 173.6 289.3
425 5.5 28.8 38.4 57.5 86.3 143.8 239.7
450 4.6 23 30.7 46 69 115 191.7
475 3.7 17.4 23.2 34.9 52.3 87.2 145.3
500 2.8 11.8 15.7 23.5 35.3 58.8 97.9
538 1.4 5.9 7.9 11.8 17.7 29.5 49.2
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 PRESSURE AND TEMPERATURE RATINGS FOR ASTM A182 F304-F316-F317 (working pressure by Class, in bar)

TEMP. C 150# 300# 400# 600# 900# 1500# 2500#
-29 to 38 15.9 41.4 55.2 82.7 124.1 206.8 344.7
50 15.3 40 53.4 80 120.1 200.1 333.5
100 13.3 34.8 46.4 69.6 104.4 173.9 289.9
150 12 31.4 41.9 62.8 94.2 157 261.6
200 11.2 29.2 38.9 58.3 87.5 145.8 243
250 10.5 27.5 36.6 54.9 82.4 137.3 228.9
300 10 26.1 34.8 52.1 78.2 130.3 217.2
325 9.3 25.5 34 51 76.4 127.4 212.3
350 8.4 25.1 33.4 50.1 75.2 125.4 208.9
375 7.4 24.8 33 49.5 74.3 123.8 206.3
400 6.5 24.3 32.4 48.6 72.9 121.5 202.5
425 5.5 23.9 31.8 47.7 71.6 119.3 198.8
450 4.6 23.4 31.2 46.8 70.2 117.1 195.1

 COMMON FORGING MATERIALS

ASTM DESIGN. DESCRIPTION SERVICE CASTING COMPARISON
A105(1) Carbon Steel General service such as oil, oil vapor, gas, steam and water at temperatures -20°F to 1000°F (-28°C to 537°C). A216-WCB
A350-LF2 CL1 Low Temperature Carbon Steel Suitable for temperatures -50°F and not above 650°F (-46°C and not above 343°C). A352-LCB
A182-F11 CL2 1 1/4% Cr, 1/2% Mo Alloy Steel High temperatures from -20°F to 1100°F to minimize graphitization (-28°C to 593§C). A217-WC6
A182-F22 CL3 (2) 2 1/4% Cr, 1% Mo Alloy Steel For services requiring greater strength than F11 at temperatures from -20°F to 1100°F (-28°C to 593°C). A217-WC9
A182-F5 5% Cr, 1/2% Mo Alloy Steel For corrosive/erosive refinery use requiring resistance at temperatures from -20°F to 1100§F (-28°C to 590°C). A217-C5
A182-F9 9% Cr, 1% Mo Alloy Steel For services involving media with higher Sulphur content to combat oxidation to 1100oF (593°C). A217-C12
A182-F304 18% Cr, 8% Ni Stainless Steel For corrosive services and atmospheres from -450°F to 1000°F (-268°C to 537°C). A351-CF8
A182-F316 18% Cr, 8% Ni, 2% Mo Stainless Steel For superior resistance to corrosion from -450°F to 1000°F (-268°C to 537°C). A351-CF8M

Notes:

  1. Allowed but not recommended for long term use above 800oF (425oC)
  2. Warning to the possibility of excessive oxidation (scaling) when used above 1050oF (563oC)
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 SPECIAL FORGING MATERIALS

MATERIAL DESCRIPTION SERVICE
HASTELLOY FLANGES
(C2, C4, B2, C276…)
Nickel Alloy Good high temperature properties. Excellent corrosion resistance in hydrochloric acid.
INCONEL 600 FLANGES / INCONEL 625 FLANGES / INCOLOY 800 FLANGES Nickel Alloy For high temperature service. Nuclear applications.
MONEL 400 / MONEL K500 (MONEL FLANGES) Nickel-Copper Alloy For corrosive service up to 842oF (450oC). Resistant to sea water, acids, alkalies.
TITANIUM GR 1-GR 11 (TITANIUM FLAGES) Transition Metal Good resistance to corrosion together with low specific weight.
ASTM A182 F20 (ALLOY 20 FLANGES) Alloy 20 - Specialty Alloy For corrosive service such as hot sulphuric acid. Resists -49oF to 600oF (-45oC to 316oC).
ASTM A182 F51 (DUPLEX FLANGES; SUPERDUPLEX FLANGES) Ferritic-Austenitic Stainless Steel Very high strength, resistance to corrosion, pitting and stress corrosion in chloride media.
ASTM A182 F44 Austenitic Stainless Steel Very high strength, high resistance to corrosion.

 CHEMICAL COMPOSITION ASTM A105 – CARBON STEEL FORGINGS FOR PIPING APPLICATIONS

Composition, %
Element C Mn P S Si Cu Ni Cr Mo V
  0.35 max 0.60-1.05 0.035 max 0.040
max
0.10-0.35 0.40
max (1)
0.40
max (1)
0.30
max (1-2)
0.12
max (1-2)
0.08
max

Notes:

  1. The total of Cu, Ni, Niobium, Moly and Vanadium shall not exceed 1.00%.
  2. The sum of Niobium and Molybdenum shall not exceed 0.32%.
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 CHEMICAL COMPOSITION ASTM A182 STAINLESS STEEL

Composition, %
Grade C Mn P S Si Ni Cr Mo Nb Ti Others
F304(1) 0.08 2.0 0.045 0.030 1.0 8.0-11.0 18.0-20.0        
F304H 0.04-0.10 2.0 0.045 0.030 1.0 8.0-11.0 18.0-20.0        
F304L(1) 0.030 2.0 0.045 0.030 1.0 8.0-13.0 18.0-20.0        
F304N(2) 0.08 2.0 0.045 0.030 1.0 8.0-10.5 18.0-20.0        
F304LN(2) 0.030 2.0 0.045 0.030 1.0 8.0-10.5 18.0-20.0        
F309H 0.04-0.10 2.0 0.045 0.030 1.0 12.0-15.0 22.0-24.0        
F310 0.25 2.0 0.045 0.030 1.0 19.0-22.0 24.0-26.0        
F310H 0.04-0.10 2.0 0.045 0.030 1.0 19.0-22.0 24.0-26.0        
F310MoLN 0.030 2.0 0.030 0.015 0.40 21.0-23.0 24.0-26.0 2.0-3.0     N 0.10-0.16
F316 0.08 2.0 0.045 0.030 1.0 10.0-14.0 16.0-18.0 2.0-3.0      
F316H 0.04-0.10 2.0 0.045 0.030 1.0 10.0-14.0 16.0-18.0 2.0-3.0      
F316L(1) 0.030 2.0 0.045 0.030 1.0 10.0-15.0 16.0-18.0 2.0-3.0      
F316N(2) 0.08 2.0 0.045 0.030 1.0 11.0-14.0 16.0-18.0 2.0-3.0      
F316LN(2) 0.030 2.0 0.045 0.030 1.0 11.0-14.0 16.0-18.0 2.0-3.0      
F316Ti 0.08 2.0 0.045 0.030 1.0 10.0-14.0 16.0-18.0 2.0-3.0   (3) N 0.10 max
F317 0.08 2.0 0.045 0.030 1.0 11.0-15.0 18.0-20.0 3.0-4.0      
F317L 0.030 2.0 0.045 0.030 1.0 11.0-15.0 18.0-20.0 3.0-4.0      
F321 0.08 2.0 0.045 0.030 1.0 9.0-12.0 17.0-19.0     (4)  
F321H 0.04-0.10 2.0 0.045 0.030 1.0 9.0-12.0 17.0-19.0     (5)  
F347 0.08 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0   (6)    
F347H 0.04-0.10 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0   (7)    
F348 0.08 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0   (6)   Co 0.20
Ta 0.10
F348H 0.04-0.10 2.0 0.045 0.030 1.0 9.0-13.0 17.0-20.0   (7)   Co 0.20
Ta 0.10

Notes:

  1. Grades F304, F304L, F316, and F316L shall have a maximum Nitrogen of 0.10%.
  2. Grades F304N, F316N, F304LN, and F316LN shall have a Nitrogen of 0.10 to 0.16%.
  3. Grade F316Ti shall have a Titanium content five times above the Carbon plus Nitrogen and not more than 0.70%.
  4. Grade F321 shall have a Titanium content five times above the Carbon and not more than 0.70%.
  5. Grade F321H shall have a Titanium content four times above the Carbon and not more than 0.70%.
  6. Grades F347 and F348 shall have a Niobium content ten times above the Carbon and not more than 1.10%.
  7. Grades F347H and F348H shall have a Niobium content above than eight times the Carbon and not more than 1.10%.

 MECHANICAL PROPERTIES OF FLANGE MATERIALS

Flange mechanical requirements

(Source Trouvay & Cauvin - Piping equipment "Blue book")

 CONVERSION TABLE ASTM / EN FLANGES MATERIALS

Flanges
Material number EN AStM
Non-alloy
1.0038 RSt 37-2 S235JR -
1.0570 St 52-3 S355J2 (1.0577) -
1.0460 C 22.8 P250GH -
1.0432 C 21 - A 105
1.0352 - P245GH -
- - - -
Alloyed heat-resistant
1.5415 15 Mo 3 16Mo3 A 182 Grade F 1
1.7335 13 CrMo 4 4 13CrMo4-5 A 182 Grade F11, F12
1.7380 10 CrMo 9 10 11CrMo9-10 (1.7383) A 182 Grade F22
1.7362 12 CrMo 19 5 - A 182 Grade F5
- - - A 182 Grade F9
1.4903 - X10CrMoVNb9-1 A 182 Grade F91
Low temperature
1.5637 10 Ni 14 12Ni14 A 350 Grade LF3
1.0566 TStE 355 P355QH1 (1.0571) A 350 Grade LF2
- - - -
- - - -
Fine-grain steels
- - - -
1.0486 StE 285 - A 694 Grade F42
1.0562 StE 355 P355N A 694 Grade F52
1.8902 StE 420 P420N A 694 Grade F60
1.8905 StE 460 P460N A 694 Grade F70
High yield steels
- - - -
- - - -
- - - -
- - - -
- - - -
Stainless steel
1.4541 X 6 CrNiTi 18 10 X6CrNiTi18-10 A 182 Grade F321
1.4571 X 6 CrNiMoTi 17 12 2 X6CrNiMoTi17-12-2 A 182 Grade F316Ti
1.4301 X 5 CrNi 18 10 X5CrNi18-10 A 182 Grade F304
1.4306 X 2 CrNi 19 11 - A 182 Grade F304L
1.4307 - X2CrNi18-9 A 182 Grade F304L
1.4401 X 5 CrNiMo 17 12 2 X5CrNiMo17-12-2 A 182 Grade F316
1.4404 X 2 CrNiMo 17 13 2 X2CrNiMo17-12-2 A 182 Grade F316L
1.4462 X 2 CrNiMoN 22 5 3 X2CrNiMoN22-5-3 A 182 Grade F51 (Duplex)
1.4529 X 1 NiCrMoCuN 25 20 6 X1NiCrMoCuN25-20-7 UNS N 08926
1.4539 X 1 NiCrMoCuN 25 20 5 X1NiCrMoCu25-20-5 A 182 Grade F904L
1.4547 - X1CrNiMoCuN20-18-7 UNS S 31254
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