ASME B16.9 Incoloy 800H Pipe Cap Dimensions
ASME B16.9 pipe caps are critical protective devices that seal pipeline ends, preventing fluid leakage, containing pressure, and protecting against environmental contaminants. Manufactured to strict international standards, ASME B16.9 caps ensure reliable performance in demanding environments, from chemical processing to high-temperature applications.
The standard covers factory-made wrought butt-welding fittings in sizes from NPS 1/2" to NPS 48" (DN 15 to DN 1200), including detailed specifications for overall dimensions, tolerances, ratings, testing, and markings.
Incoloy 800H: Material Properties and Advantages
Incoloy 800H is a nickel-iron-chromium alloy for high-temperature applications. The "H" designation indicates higher carbon content compared to standard Incoloy 800, which enhances its creep rupture strength at elevated temperatures. This alloy has excellent resistance to oxidation and carburization, making it ideal for applications in furnace components, heat treatment equipment, and petrochemical processing systems where temperatures can exceed 1000°F.
The combination of nickel content (30-35%) and chromium content (19-23%) provides outstanding corrosion resistance, while the addition of aluminum and titanium contributes to its high-temperature strength through precipitation hardening. These properties make Incoloy 800H pipe caps valuable in applications where both corrosion resistance and thermal stability are needed.
ASME B16.9 Pipe Caps Dimensions
The following table presents the essential dimensions for ASME B16.9 pipe caps based on the standard specifications. These dimensions apply to Incoloy 800H caps, with specific measurements varying according to the nominal pipe size (NPS):
|
Nominal Pipe Size (NPS) |
DN |
Outside Diameter at Bevel |
Length, E |
Limiting Wall Thickness for Length, E |
Length, E |
|
1/2 3/4 1 1 1/4 1 1/2 2 2 1/2 3 3 1/2 4 5 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 |
15 20 25 32 40 50 65 80 90 100 125 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000 1050 1100 1150 1200 |
21.3 26.7 33.4 42.2 48.3 60.3 73.0 88.9 101.6 114.3 141.3 168.3 219.1 273.0 323.8 355.6 406.4 457 508 559 610 660 711 762 813 864 914 965 1016 1067 1118 1168 1219 |
25 25 38 38 38 38 38 51 64 64 76 89 102 127 152 165 178 203 229 254 267 267 267 267 267 267 267 305 305 305 343 343 343 |
4.57 3.81 4.57 4.83 5.08 5.59 7.11 7.62 8.13 8.64 9.65 10.92 12.70 12.70 12.70 12.70 12.70 12.70 12.70 12.70 12.70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
25 25 38 38 38 44 51 64 76 76 89 102 127 152 178 191 203 229 254 254 305 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
Wall Thickness and Schedule
Incoloy 800H pipe caps are available in various wall thickness schedules to accommodate different pressure requirements. The most common schedules include Sch 5S, 10S, 40S, 80S, 160S, and XXS. The wall thickness directly influences the pressure-containing capability of the cap, with heavier schedules providing greater strength for high-pressure applications.
For standard weight caps, the wall thickness typically matches that of Schedule 40 pipes for sizes up to NPS 10, while extra strong (XS) caps correspond to Schedule 80 thicknesses. The actual thickness values vary by nominal pipe size, with detailed specifications provided in ASME B16.9.
Dimensional Tolerances for ASME B16.9 Pipe Caps
To ensure proper installation and function, ASME B16.9 establishes precise dimensional tolerances for pipe caps.
|
Dimension |
Tolerance Range |
|
Outside Diameter at Bevel |
+1/-1 mm for NPS 1/2 to 2½ |
|
Wall Thickness |
Not less than 87.5% of nominal thickness |
|
Overall Length (E) |
±1.5 mm (1/16 inch) |
|
Inside Diameter at End |
±0.8 mm for NPS 1/2 to 2½ |
These tight tolerances ensure proper fit-up during welding operations and maintain the structural integrity of the piping system.
Incoloy 800H Pipe Caps Weight
The weight of Incoloy 800H pipe caps varies significantly based on both size and schedule. The approximate weights for standard incoloy 800H pipe caps are as follows:
|
NPS |
Schedule 5S/10S (kg) |
Schedule 40/STD (kg) |
Schedule 80/XS (kg) |
Schedule 160 (kg) |
|
1/2 |
0.04 |
0.05 |
0.05 |
- |
|
3/4 |
0.05 |
0.06 |
0.08 |
- |
|
1 |
0.09 |
0.13 |
0.17 |
0.18 |
|
1¼ |
0.11 |
0.15 |
0.18 |
0.23 |
|
1½ |
0.15 |
0.20 |
0.22 |
0.27 |
|
2 |
0.17 |
0.25 |
0.30 |
0.57 |
|
2½ |
0.25 |
0.45 |
0.50 |
0.79 |
|
3 |
0.40 |
0.70 |
0.90 |
1.32 |
|
4 |
0.60 |
1.20 |
1.60 |
2.68 |
|
6 |
1.40 |
2.90 |
4.30 |
6.80 |
|
8 |
2.50 |
5.10 |
7.60 |
14.06 |
|
10 |
3.90 |
9.00 |
12.00 |
25.85 |
|
12 |
6.50 |
13.50 |
17.50 |
43.09 |
Note: Weights are approximate, based on a density of 8 kg/cm³. Actual weight may vary depending on manufacturing process and specific material composition.
The higher density of Incoloy 800H compared to carbon steel means that caps made from this alloy will be heavier than carbon steel caps of the same size.
Manufacturing Processes and Quality Standards
Manufacturing Methods
Incoloy 800H pipe caps are produced using two primary manufacturing methods:
Seamless Construction: Created through hot forming processes without any welding, seamless caps offer superior dimensional accuracy and structural integrity. They are typically available in sizes from 1/2" to 10" and are preferred for high-pressure applications.
Welded/Fabricated Construction: Formed from plate or sheet material with a longitudinal weld, fabricated caps are economical for larger sizes (typically 1/2" to 48"). Advanced manufacturing techniques ensure the weld quality meets the required specifications for intended service conditions.
Quality Assurance and Compliance
ASME B16.9 Incoloy 800H pipe caps must comply with several quality standards and testing requirements:
Material Certification: ASTM B408 for bar forms, ASTM B409 for plate forms, with heat verification
Non-Destructive Testing: 100% radiography for critical applications
Dimensional Verification: Full compliance with ASME B16.9 dimensional requirements
Surface Inspection: Freedom from defects that might impair serviceability
Incoloy 800H Cap Installation
Proper installation of Incoloy 800H caps requires attention to welding procedures and post-weld heat treatment:
Welding Preparation: Beveling the cap according to ASME B16.25.
Welding Materials: Use matching welding wire, such as ENiCrFe-2 or ENiCrFe-3.
Welding Procedure: Employ a low heat input welding method to minimize deformation.
Post-weld Heat Treatment: Depending on the operating conditions, perform solution annealing at 1650-1750°F (899-954°C), followed by rapid cooling.
The coefficient of thermal expansion of Incoloy 800H (14.1-14.2 μm/m·°C at 24-100°C) should be considered in the system design to compensate for differential expansion with the connecting pipe materials.
Conclusion
ASME B16.9 Incoloy 800H pipe caps provide reliable end closures for high-temperature and corrosive service applications across multiple industries. Understanding the dimensions, tolerances, weights, and application considerations is essential for proper specification, procurement, and installation of these critical piping components.
When selecting Incoloy 800H pipe caps, you must consider not only the dimensional requirements but also the specific service conditions, including temperature, pressure, corrosion media, and mechanical stresses.
