Views: 19 Author: Site Editor Publish Time: 2025-07-30 Origin: Site
ASME B16.11 threaded pipe fittings are widely used in high-pressure industrial piping systems across a wide range of environments due to their high-pressure resistance, ease of installation, and wide applicability. Whether in the petrochemical, power, shipbuilding, or food and pharmaceutical industries, threaded connections are the preferred method due to their strong sealing properties and high-pressure resistance.
ASME B16.11 is the most common American standard for threaded pipe fittings. This standard covers a wide range of sizes, from 1/8 inch to 4 inch, with pressure ratings of Class 2000, Class 3000, and Class 6000. These features ensure the safety and stability of piping systems in various pressure environments.
ASME B16.11, a standard developed by the American Society of Mechanical Engineers (ASME), specifically applies to forged pipe fittings for socket welding and threaded connections. It specifies dimensions, materials, pressure ratings, and testing requirements to ensure safety and durability in harsh operating conditions.
Threaded pipe fittings are connections made using threads (such as NPT and BSP) and are suitable for small-diameter, high-pressure piping systems (typically under DN100). They are widely used in applications where frequent disassembly is required or where space is limited.
Size | 1/8″ to 4″ NPS |
Pressure Ratings | Class 2000, 3000, 6000 |
Material | ASTM A105/ASTM A350 LF2/ASTM A182 F304/304L,316/316L,904L |
Application | Oil and gas / Pipelines / Power industry /Chemical industry |
Based on their structure and function, ASME B16.11 threaded fittings are primarily classified into threaded elbows, threaded tees, threaded crosses, threaded caps, threaded clamps, and other types.
(1) Threaded Elbow
45° and 90° elbows: used to change the direction of the pipeline and reduce fluid resistance.
(2) Threaded Tee
Equal Tee: three ports of the same size, used for diversion or merging.
Reducing Tee: one port size is different, suitable for reducing connection.
(3) Threaded Cross
Used for four-way pipe intersection, commonly used in complex diversion systems.
(4) Threaded Cap
Used to seal the pipe end to prevent leakage or contamination.
(5) Threaded Coupling
Full Coupling: both ends are internally threaded, used to connect two externally threaded pipes.
Half Coupling: one end is welded and the other end is threaded, suitable for equipment interface.
(6) Hex nipple
Hex nipple is a short pipe joint with a hexagonal middle section and external threads (usually NPT threads) at both ends. It is one of the threaded pipe fittings in the ASME B16.11 standard. Its name comes from the hexagonal structure in the middle, which makes it easy to install and remove with a wrench.
(7)Plug
Plug is a simple but critical small component in the pipeline system, used for sealing, protection or reserving maintenance ports. Selecting the appropriate material, thread type and head design according to the medium, pressure and disassembly frequency can significantly improve the safety and maintenance convenience of the system.
Hex head plug: can be tightened with a wrench, suitable for high pressure or anti-loosening situations.
Square head plug: suitable for manual tool operation.
Round head plug: smooth appearance to avoid bumps.
(8) Bushings
A bushing is a pipe fitting used for pipe reducer connections. It can convert a large-diameter threaded port to a smaller one, or between different thread standards. Its core function is to adapt to pipes or equipment interfaces of different sizes.
Threaded 45 Elbow | Threaded 45 ° Elbow | Threaded Tee | Threaded Cross | ||||||||||||
ASME B16.11 | |||||||||||||||
Nominal Size | Center-to-End | Outside Diameter of Band | Wall Thickness | Length of Thread | |||||||||||
DN | NPS | A | H | G min | L5 min | L2 min | |||||||||
90° Elbows, Tees, Crosses | 45 ° Elbows | ||||||||||||||
2000 | 3000 | 6000 | 2000 | 3000 | 6000 | 2000 | 3000 | 6000 | 2000 | 3000 | 6000 | ||||
6 | 1/8 | 21 | 21 | 25 | 17 | 17 | 19 | 22 | 22 | 25 | 3.18 | 3.18 | 6.35 | 6.4 | 6.7 |
8 | 1/4 | 21 | 25 | 28 | 17 | 19 | 22 | 22 | 25 | 33 | 3.18 | 3.30 | 6.60 | 8.1 | 10.2 |
10 | 3/8 | 25 | 28 | 33 | 19 | 22 | 25 | 25 | 33 | 38 | 3.18 | 3.51 | 6.98 | 9.1 | 10.4 |
15 | 1/2 | 28 | 33 | 38 | 22 | 25 | 28 | 33 | 38 | 46 | 3.18 | 4.09 | 8.15 | 10.9 | 13.6 |
20 | 3/4 | 33 | 38 | 44 | 25 | 28 | 33 | 38 | 46 | 56 | 3.18 | 4.32 | 8.53 | 12.7 | 13.9 |
25 | 1 | 38 | 44 | 51 | 28 | 33 | 35 | 46 | 56 | 62 | 3.68 | 4.98 | 9.93 | 14.7 | 17.3 |
32 | 1 1/4 | 44 | 51 | 60 | 33 | 35 | 43 | 56 | 62 | 75 | 3.89 | 5.28 | 10.59 | 17.0 | 18.0 |
40 | 1 1/2 | 51 | 60 | 64 | 35 | 43 | 44 | 62 | 75 | 84 | 4.01 | 5.56 | 11.07 | 17.8 | 18.4 |
50 | 2 | 60 | 64 | 53 | 43 | 44 | 52 | 75 | 84 | 102 | 4.27 | 7.14 | 12.09 | 19.0 | 19.2 |
65 | 2 1/2 | 76 | 83 | 95 | 52 | 52 | 64 | 92 | 102 | 121 | 5.61 | 7.65 | 15.29 | 23.6 | 28.9 |
80 | 3 | 86 | 95 | 106 | 64 | 64 | 79 | 109 | 121 | 146 | 5.99 | 8.84 | 16.64 | 25.9 | 30.5 |
100 | 4 | 106 | 114 | 114 | 79 | 79 | 79 | 146 | 152 | 152 | 6.55 | 11.18 | 18.67 | 27.7 | 33 |
Coupling | Half-Coupling | Boss | Cap | |||||||
Nominal Size | End-to-End | End-to-End | Outside Diameter | End Wall | Length of Thread | |||||
DN | NPS | W | P | D | G min | L5 min | L2 min | |||
3000 & 6000 | 3000 | 6000 | 3000 | 6000 | 3000 | 6000 | ||||
6 | 1/8 | 32 | 19 | 16 | 22 | 4.8 | 6.4 | 6.7 | ||
8 | 1/4 | 35 | 25 | 27 | 19 | 25 | 4.8 | 6.4 | 8.1 | 10.2 |
10 | 3/8 | 38 | 25 | 27 | 22 | 32 | 4.8 | 6.4 | 9.1 | 10.4 |
15 | 1/2 | 48 | 32 | 33 | 28 | 38 | 6.4 | 7.9 | 10.9 | 13.6 |
20 | 3/4 | 51 | 37 | 38 | 35 | 44 | 6.4 | 7.9 | 12.7 | 13.9 |
25 | 1 | 60 | 41 | 43 | 44 | 57 | 9.7 | 11.2 | 14.7 | 17.3 |
32 | 1 1/4 | 67 | 44 | 46 | 57 | 64 | 9.7 | 11.2 | 17.0 | 18.0 |
40 | 1 1/2 | 79 | 44 | 48 | 64 | 76 | 11.2 | 12.7 | 17.8 | 18.4 |
50 | 2 | 86 | 48 | 51 | 76 | 92 | 12.7 | 15.7 | 19.0 | 19.2 |
65 | 2 1/2 | 92 | 60 | 64 | 92 | 108 | 15.7 | 19.0 | 23.6 | 28.9 |
80 | 3 | 108 | 65 | 68 | 108 | 127 | 19.0 | 22.4 | 25.9 | 30.5 |
100 | 4 | 121 | 68 | 75 | 140 | 159 | 22.4 | 28.4 | 27.7 | 33.0 |
Nominal Size | Elbows,Tees & Crosses | Couplings | Half- couplings | |
Center-to-End | End-to-End | End-to-End | ||
DN | NPS |
| W | W/ 2 |
6~8 | 1/8~1/4 | ± 1.0 | ± 1.0 | ± 1.0 |
10~20 | 3/8~3/4 | ± 1.5 | ± 1.5 | ± 1.5 |
25~50 | 1~2 | ± 2.0 | ± 2.0 | ± 2.0 |
65~100 | 21/2~4 | ± 2.5 | ± 2.5 | ± 2.5 |
(1) Commonly used materials
Material standards and grades of threaded pipe fittings
Carbon steel
ASTM A105 / A105N
Features: corrosion resistance, strong pressure bearing capacity, easy installation
Low-temperature steel
ASTM A350 LF2 / LF3
Features: excellent low-temperature resistance, good mechanical properties, corrosion resistance and hydrogen embrittlement resistance
Pipeline steel
A694 F42 / 46 / 52 / 56 / 65 / 70
Features: high tensile strength and toughness, relatively low raw material price.
Alloy steel
ASTM A182 F5 / F9 / F11 / F12 / F22 / F91 / F92
Features: excellent wear resistance, able to maintain a long service life in high wear environment
Stainless steel
A182 F304/304L/304H - F904L
Features: corrosion resistance, high strength, good high and low temperature resistance, non-magnetic, high surface finish, easy processing and installation, environmental protection and recyclability.
(2) Pressure rating
Class 2000, 3000, 6000: Corresponding to different working pressures, the larger the value, the stronger the pressure bearing capacity.
Joint Type | Class | Grade of Connecting Pipes |
THRD | 2000 | Sch80/XS |
3000 | Sch160 | |
6000 | XXS |
Easy installation
Removable
High sealing
Wide application
Determine the pipe size
Select the material
Confirm the thread standard (NPT, BSPP, BSPT, etc.).
Check the pressure rating (Class 3000, 6000, etc.).
ASME B16.11 threaded pipe fittings are available in a wide variety to meet the needs of diverse industrial scenarios. Whether in the petroleum, chemical, power, or water treatment industries, choosing the right threaded fittings can improve system safety and efficiency. If you require high-quality ASME B16.11 threaded pipe fittings, please contact us and we will provide you with professional products and technical support!
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