Which coating best suits Stainless steel 904L flanges used in offshore oil and gas production?
This stainless steel grade comprises chromium (max 23%), nickel (25%) and molybdenum (4.5%). Stainless steel 904L flanges work in offshore oil and gas production, mainly for well-piping and equipment. A protective coating enhances the corrosion resistance and overall endurance of a UNS N08904 RTJ flange in stringent conditions.
One of the best options is fusion-bonded epoxy (FBE). It uses an epoxy resin and a polyamine hardener to resist high temperatures and abrasive agents.
What are the main differences between forging, casting, and machining in manufacturing a 904L stainless steel flange?
Manufacturers use forging, casting, and cutting or machining to produce a 904L stainless steel flange. The differences lie in the dimensional precision, mechanical and chemical properties, and surface defects.
Casting produces a precise and streamlined shape subject to surface porosity and voids. A forged 904L SS socket weld flange shows superior ductility and rust resistance. However, it is unsuitable for specific shapes or customization.
Finally, cutting or machining uses a central plate to slice off the desired flanges with power tools. It helps produce DIN 1.4539 lapped joint flanges with tight dimensional tolerance. This method is cheaper than forging but lower in strength.
What is the difference between an SA 182 904L slip-on flange and an AISI 904L weld neck flange?
Slip-on flanges get slipped over the pipe end and then welded in their place. They are easy to install and also inexpensive in comparison.
However, an AISI 904L weld neck flange has a longer neck that gets welded to create a much sturdier seal. It is better suited to high pressures, temperatures, and vibrations.
Material | Types | Sizes |
---|---|---|
Stainless steel 904l |
|
|
Test Certificates | ASME | WNR |
|
|
1.4539 |
Pressure Rating | UNS | DIN Pressure |
Class 150 to Class 2500 | UNS N08904 | PN 6 to PN64 |
Products | Price |
STAINLESS STEEL 904L BLIND FLANGES 600 # RF | US $ 3.33 per kg |
SA 182 F904L SORF FLANGES, ANSI B16.5 DN100,150# | US $ 5.97 per kg |
A182GR F904L SW RF FLANGES, ANSI B16.5 40S BORE,300# | US $ 2.89 per piece |
A182 F904L Forged Flange
SUS 904L Slip on Flange
DIN 1.4539 Blind Flange
SA182 Gr F904L Weld Neck Flanges
AISI 904L Plate Flange
ASTM A182 Grade F904L Lap Joint Flange
A182 Gr F904L Threaded Flange
SA182 F904L Ring and Spacer
Inox 904L Spectacle Blind Flange
904L SS Long weld neck flange
SA182 F904L Reducing Flange
SUS 904L Expander Flange
904L Stainless Steel Socket Weld Flange
A182 F904L RTJ Flanges
904L Stainless Steel Ring Joint Flanges
SA182 F904L BLRF Flanges
904L SS SORF Flanges
SA182 Gr F904L Raised Face Flange
ASTM A182 Grade F904L Tongue and groove flange
904L SS WNRF Flanges
Stainless Steel 904L SWRF Flanges
Inox 904L Flat Face Flanges
AISI 904L Pipe Flanges
UNS N08904 Exhaust flanges
Class 150 A182 Gr F904L flanges
Class 300 SA182 F904L flange
Class 600 ASTM A182 F904L pipe flanges
Class 900 904L Stainless Steel flanges
Class 1500 DIN 1.4539 plate flange
Class 2500 ASTM A182 F904L flanges
Nominal Size | Outside Diameter (OD) | Bore Diameter (B) | No. of Bolt Holes | Bolt Hole Diam. | Bolt Circle (BC) | Thickness (T) | Hub Length (L) | Hub Diam. (H) | Lap Radius ( R ) | Approx. Weight (lbs) |
---|---|---|---|---|---|---|---|---|---|---|
1 | 4.25 | 1.38 | 4 | 0.625 | 3.13 | 0.563 | 0.688 | 1.938 | 0.13 | 2 |
1 1/4 | 4.68 | 1.72 | 4 | 0.625 | 3.50 | 0.625 | 0.813 | 2.312 | 0.19 | 3 |
1 1/2 | 5.00 | 1.97 | 4 | 0.625 | 3.88 | 0.688 | 0.875 | 2.563 | 0.25 | 3 |
2 | 6.00 | 2.46 | 4 | 0.750 | 4.75 | 0.750 | 1.000 | 3.063 | 0.31 | 5 |
2 1/2 | 7.00 | 2.97 | 4 | 0.750 | 5.50 | 0.875 | 1.125 | 3.563 | 0.31 | 7 |
3 | 7.50 | 3.60 | 4 | 0.750 | 6.00 | 0.938 | 1.188 | 4.250 | 0.38 | 8 |
3 1/2 | 8.50 | 4.10 | 8 | 0.750 | 7.00 | 0.938 | 1.250 | 4.812 | 0.38 | 11 |
4 | 9.00 | 4.60 | 8 | 0.750 | 7.50 | 0.938 | 1.312 | 5.312 | 0.44 | 13 |
5 | 10.00 | 5.69 | 8 | 0.875 | 8.50 | 0.938 | 1.438 | 6.438 | 0.44 | 15 |
6 | 11.00 | 6.75 | 8 | 0.875 | 9.50 | 1.000 | 1.562 | 7.562 | 0.50 | 18 |
8 | 13.50 | 8.75 | 8 | 0.875 | 11.75 | 1.125 | 1.750 | 9.688 | 0.50 | 30 |
10 | 16.00 | 10.92 | 12 | 1.000 | 14.25 | 1.188 | 1.938 | 12.000 | 0.50 | 42 |
12 | 19.00 | 12.92 | 12 | 1.000 | 17.00 | 1.250 | 2.188 | 14.375 | 0.50 | 64 |
14 | 21.00 | 14.19 | 12 | 1.125 | 18.75 | 1.375 | 2.250 | 15.750 | 0.50 | 90 |
16 | 23.50 | 16.19 | 16 | 1.125 | 21.25 | 1.438 | 2.500 | 18.000 | 0.50 | 98 |
18 | 25.00 | 18.20 | 16 | 1.250 | 22.75 | 1.562 | 2.688 | 19.875 | 0.50 | 125 |
20 | 27.50 | 20.25 | 20 | 1.250 | 25.00 | 1.688 | 2.875 | 22.000 | 0.50 | 160 |
24 | 32.00 | 24.25 | 20 | 1.375 | 29.50 | 1.875 | 3.250 | 26.125 | 0.50 | 212 |
30** | 38.75 | 30.25 | 28 | 1.375 | 36.00 | 2.125 | 3.500 | 32.750 | 0.50 | 305 |
36** | 46.00 | 36.25 | 32 | 1.625 | 42.75 | 2.375 | 3.750 | 39.250 | 0.50 | 440 |
Grade | Mn | C | Si | S | P | Cu | Cr | Mo | Ni |
---|---|---|---|---|---|---|---|---|---|
SS 904L | 2.00 max | 0.020 max | 1.00 max | 0.030 max | 0.040 max | 1.00 – 2.00 | 19.00 – 23.00 | 4.00 – 5.00 max | 23.00 – 28.00 |
Melting Point | Density | Tensile Strength | Elongation | Yield Strength (0.2%Offset) |
---|---|---|---|---|
1350 °C (2460 °F) | 7.95 g/cm3 | Psi – 71000 , MPa – 490 | 35 % | Psi – 32000 , MPa – 220 |
Grade | EN | UNS | WERKSTOFF NR. | JIS | BS | KS | AFNOR |
---|---|---|---|---|---|---|---|
SS 904L | X1NiCrMoCu25-20-5 | N08904 | 1.4539 | SUS 904L | 904S13 | STS 317J5L | Z2 NCDU 25-20 |
Grade | Density (g/cm3) | Elastic Modulus (GPa) | Mean Co-eff of Thermal Expansion (μm/m/°C) | Thermal Conductivity (W/m.K) | Melting Range | Specific Heat ( J/Kg.K) | Electrical Resistivity (μΩ.m) |
---|---|---|---|---|---|---|---|
SS 904L | 8 | 190 | 20-100°C | at 100°C | 1300-1390 | 0-100°C | at 20°C |
15.3 | 12.9 | 450 | 1 |
Temperature °F | Class 150 | Class 900 | Class 600 | Class 300 | Class 2500 | Class 1500 | Class 400 |
-20 to 100 | 275 | 2160 | 1440 | 720 | 6000 | 3600 | 960 |
300 | 205 | 1620 | 1080 | 540 | 4500 | 2700 | 720 |
200 | 230 | 1800 | 1200 | 600 | 5000 | 3000 | 800 |
400 | 190 | 1490 | 995 | 495 | 4140 | 2485 | 660 |
600 | 140 | 1310 | 875 | 435 | 3640 | 2185 | 580 |
650 | 125 | 1290 | 860 | 430 | 3580 | 2150 | 575 |
500 | 170 | 1395 | 930 | 465 | 3880 | 2330 | 620 |
700 | 110 | 1275 | 850 | 425 | 3540 | 2125 | 565 |
750 | 95 | 1245 | 830 | 415 | 3460 | 2075 | 555 |
850 | 65 | 1190 | 790 | 395 | 3300 | 1980 | 530 |
800 | 80 | 1210 | 805 | 405 | 3360 | 2015 | 540 |
900 | 50 | 1165 | 780 | 390 | 3240 | 1945 | 520 |
950 | 35 | 1145 | 765 | 380 | 3180 | 1910 | 510 |
1000 | 20 | 965 | 640 | 320 | 2675 | 1605 | 430 |
1100 | 20 | 770 | 515 | 255 | 2145 | 1285 | 345 |
1150 | 20 | 595 | 400 | 200 | 1655 | 995 | 265 |
1050 | 20 | 925 | 615 | 310 | 2570 | 1545 | 410 |
1200 | 20 | 465 | 310 | 155 | 1285 | 770 | 205 |
1250 | 20 | 340 | 225 | 115 | 945 | 565 | 150 |
1300 | 20 | 255 | 170 | 85 | 715 | 430 | 115 |
1400 | 20 | 145 | 95 | 50 | 400 | 240 | 65 |
1350 | 20 | 185 | 125 | 60 | 515 | 310 | 80 |
1450 | 15 | 105 | 70 | 35 | 285 | 170 | 45 |
1500 | 10 | 80 | 55 | 25 | 230 | 135 | 35 |
What are the causes of corrosion and rust on an SS 904L flange? How can they be prevented?
Excellent corrosion resistance is a standout property of an SS 904L flange. It tolerates seawater, chlorides, and several acids, including acetic, citric and sulphuric acids. An SA 182 904L slip on flange withstands corrosion in most forms, like pitting, intergranular corrosion, and stress-induced cracking.
However, corrosion might get triggered upon prolonged exposure to hydrofluoric acid. Fluoride ions affect the passivation and reduce the corrosion resistance of 904L material. Although ASTM A182 Grade F904L reducing flanges are highly resilient, they may experience corrosion due to damage, improper cleaning, and surface defects. Selecting application-appropriate material and using corrosion-proof coating are effective solutions.
Can an ASTM A182 F904L blind flange be inspected or tested before delivery?
Blind flanges are indispensable for sealing a piping system for maintenance or repair. Thorough inspection and quality testing for performance is essential for an ASTM A182 F904L blind flange.
Manufacturers supply visual inspection reports in a Mill Test Certificate. It contains standard test reports like ultrasonic testing and assessment of hardness, tensile strength, and corrosion resistance.
Clients can also commission a third-party inspection. For instance, customers may order Inox 904L threaded flanges, the name emanating from the French for inoxydable, i.e., a stainless steel alloy with a minimum of 10.5% chromium. Chemical spectrography is essential to ascertain the composition.
What is the maximum allowable pressure for an A182 F904L plate flange connection?
Plate flanges have higher pressure ratings than other types. An A182 F904L plate flange, manufactured using flat steel plates, can handle up to 2500 lbs. The classes are from 150 to 2500. It depicts the maximum allowed pressure 904L flanges can tolerate with increasing temperatures.
These flanges operate in critical high-pressure sectors, like chemical processing, phosphate-based fertilizer production, and pharmaceuticals.