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Pipe fittings

Pipe fittings are weldable pipe fitting that allows for change of direction of flow, to branch off, reduce pipe size or attach auxiliary equipment.

Butt weld pipe fittings

Butt weld pipe fittings are weldable pipe fittings that allow for change of direction of flow, to branch off, reduce pipe size or attach auxiliary equipment.

U-bend tubes

Each U bend tube of our range is rigorously quality checked by our team of talented professionals on every stage of production to deliver the clients defect free best quality products.

Expansion joints

Expansion joints are devices containing a bellows membrane that are designed to absorb dimensional changes, such as those that occur due to thermal expansion or contraction of a pipeline, duct or vessel.

Fin tube

Fin tube is a tube with small finned fins around the outer surface of the main part of a heat exchanger.

Forged fittings

Forge & Fittings distributors both domestic and foreign forged fittings and forged pipe fittings to complete your forge, flange and bar order.

Pipe fitting is the occupation of installing or repairing piping or tubing systems that convey liquid, gas, and occasionally solid materials.

Stainless steel pipe fittings

Stainless steel pipe fitting is part that connect pipe to pipe, its purpose to connect, control and change the direction, split, sealed, support various parts and components in pipeline system, selecting and preparing proper pipe fitting to joint together, there are various types, sizes, grades & specifications to meet specific requirement.

Pipe Fittings are sized to Nominal pipe size (NPS) respectively, NPS ranges from1/2 inch to 24 inch, thicknesses are marked in schedule no, ranging from SC 5 to 80S, sizes tolerances should be controled in compliance with standard specifications in both outside and inside.

1/2” to 24” seamless type SCH 5S to XXS
2” to 48” welded type SCH 5S to XXS

Pipe Fitting Joint method

  • Butt welded pipe fittings
  • Threaded fittings
  • Sleeve pipe fittings
  • Clamp pipe fittings
  • Socket pipe fitting

Manufacturing method and process

A buttweld fitting is manufactured by the process of hot or cold forming, which means that it is bended and moulded to the correct shape. They are also heat treated to remove residual stresses and to achieve specific mechanical properties.

The ends of buttweld fittings have to be bevelled and the exact shape of the bevel depends upon the wall thickness of the pipe it is being attached to. The material of a buttweld fitting can be any one of a number of exotic materials such as super duplex, nickel alloy or 6% Moly. The majority of the time, the material of the fitting is the same as the pipe system that it is welded to.

Application Of Stainless Steel Pipe/Buttweld Fittings Industries

Buttweld fittings can be used in a wide variety of industries to alter, divide or end the flow of fluids. These operations include the following: waste treatment facilities, chemical processing, breweries, petrochemical facilities, cryogenic plants, paper production, gas processing and even nuclear power plants. The wide range of applications demonstrates the robustness of a buttweld fitting and how much this particular type of fitting is relied upon.

Packing Of Stainless Steel Pipe Fittings Materials

Butt welded stainless steel pipe fittings is stainless steel tube and fittings of the rim on the seam lap argon welding fittings, which normally takes plus welding welding.

Stainless steel material traits:

The excellent raw material of BW pipe fittings are better performance in mechanical properties and beautiful surface.

Grade Carbon Silicon Manganese Chromium Nickel Molybdenum Sulfur Phosphorous
WP 304 0,08 1,0 2.00 18.0 – 20.0 8.0 – 11.0 0,03 0,045
WP 304L 0,035 1,0 2.00 18.0 – 20.0 8.0 – 13.0 0,03 0,045
WP 316 0,08 1,0 2.00 16.0 – 18.0 10.0 – 14.0 2.00 – 3.00 0,03 0,045
WP 316L 0,035 1,0 2.00 16.0 – 18.0 10.0 – 15.0 2.00 – 3.00 0,03 0,045
WP 321 0,08 1,0 2.00 17.0 – 19.0 9.0 – 12.0 0,03 0,045

304 and 316L are the most used stainless steel grades, they are both high chromium austenitic grades, and can be met the most cases, and other grades are available, such as, 321/321H and 347/347H. Some special alloys are usually for elbow as well, like 904L, 2205.

There are also EN steel no. for opting, these equivalents include 1.4301, 1.4307, 1.4401, 1.4404, 1.4541, 1.4550, 1.4438 and 1.4539.

Stainless steel pipe fittings grades include:

  • ASTM/ASME A403 WP 304-304L-304H-304LN-304N
  • WP 316-316L-316H-316LN-316N-316Ti
  • WP 321-321H
  • WP 347-347H
  • 2205 duplex material is available.

Pipe Fitting Standards

  • ASME/ANSI B16.9 – Factory-Made Wrought Steel Butt-welding Fittings
  • ASME/ANSI B16.11 – Forged Steel Fittings, Socket-Welding and Threaded
  • ASME/ANSI B16.28 – Wrought Steel Butt-welding Short Radius Elbows and Returns
  • ASME/ANSI B16.5 – Pipe Flanges and Flanged Fittings
  • ASTM A403 – Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings

We can also provide pacified stainless steel and coated line fittings, threaded, socket-weld & coupled ends.

No job is too small or too large. Whether it’s a small project, plant shut down, line replacement, or stock requirement for ongoing operations Petropipe can help you meet your deadline.

Pipe flanges

Pipe flanges are basically plates or rings used to connect pipes, valves and other piping equipment to form a piping system.

Most common flange types

Regardless of custom sizing or specifications, the fundamental design of most flanges falls under six common styles created to close, connect, cover, or support pipes and pipe systems.

Specialty flange

A Specialty flange is a component with a flanged joint that has the same bolting structure as a standard flange, but a specialty flange has its own characteristics.

Flange accord to standard & material

The usual materials of flanges include stainless steel, carbon steel, aluminum and plastic.


End connections

There are four different type of connections that are used for fittings:

  • Butt Weld Fittings – Probably the most common type of fitting. They are easily manufactured and are easily installed. Butt weld fittings can be connected directly to each other. This is called fitting make up.
  • Flanged Fittings – Flanged fittings are piping components where the flange is an integral component of the fitting. These are most often used in water treatment applications or lined piping where welding would be destructive to the liner.
  • Socket Weld Fittings – These fittings have a socket weld connection on each end. They might be used for smaller diameter piping. These fittings utilize a single fillet weld to join the piping with the fitting.
  • Threaded Fittings – Threaded fittings are generally four inches and smaller. The reason for this size constraint is the pipe end needs to be threaded with a male type connection and die sizes are unobtainable in the larger diameters.

Fitting Weights

ASME buttweld fitting specifications do not specify weights for fittings.

Weights quoted in the tables on this page are based on manufacturers information and should be considered as approximate and provided as a guide only (fitting weights can vary considerably between manufacturers due to differences in construction).


Three groups:

Fittings are divided into three groups:

  • Buttweld (BW) fittings whose dimensions, dimensional tolerances et cetera are defined in the ASME B16.9 standards. Light-weight corrosion resistant fittings are made to MSS SP43.
  • Socket Weld (SW) fittings Class 3000, 6000, 9000 are defined in the ASME B16.11 standards.
  • Threaded (THD), screwed fittings Class 2000, 3000, 6000 are defined in the ASME B16.11 standards.

Chemical Analysis(%) For Part Standard

Standard Grade C Si Mn P S V Nb Ti Cr Mo Ni Al Nb N Others
max max max max max max max max max max max max max max max
W860WPHY420.281.300.0300.030
WPHY460.281.400.0300.030
WPHY520.281.400.0300.030
WPHY560.281.400.0300.030
WPHY600.281.400.0300.030
WPHY650.281.400.0300.030
WPHY700.281.400.0300.030
A234WPC0.281.200.0300.030
WPB0.281.200.0300.030
WP110.05-0.150.50-1.00.30-0.600.0250.0251.00-1.500.44–0.65
WP220.05-0.150.500.30-0.600.0250.0251.90-2.600.87–1.13
WP50.150.500.30-0.600.0250.0254.00-6.000.45–0.65
WP90.150.25-1.00.30-0.600.0250.0258.00-10.000.90–1.10
WP910.08-0.120.20-0.500.30-0.600.0200.0100.18–0.258.00-9.500.85–1.050.400.040.03–0.07Cb
0.06–0.10
WP920.07-0.130.50.30-0.600.0200.0100.15–0.258.50-9.500.30–0.600.400.040.03–0.07Cb
0.04–0.09 W 1.5–2.00 B
0.001–0.006

ASTM A420/A420M

Steel No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
WPL6 0.3 0.15-0.3 0.04 0.035 0.6-1.35 0.3 0.4 0.12 Cb:0.02;V:0.08 415-585 240 22
WPL9 0.2 0.03 0.03 0.4-1.06 1.6-2.24 435-610 315 20
WPL3 0.2 0.13-0.37 0.05 0.05 0.31-0.64 3.2-3.8 450-620 240 22
WPL8 0.13 0.13-0.37 0.03 0.03 0.9 8.4-9.6 690-865 515 16

ASTM A815/A815M

Steel No. Standard No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
UNS S31803 ASTM A815/A815M 0.03 0.1 0.02 0.03 2 21-23 4.5-6.5 2.5-3.5 N:0.08-0.2 620-795 450 25 290

ASTM A105/A105M

Steel No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
A105 0.35 0.1-0.35 0.04 0.035 0.6-1.05 0.3 0.4 0.12 V:0.05;Nb:0.02 485 250 22 187 ψ%:30

ASTM A182/A182M

Steel No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
F11 CL1 0.05-0.15 0.5-1 0.03 0.03 0.3-0.6 1-1.5 0.44-0.65 415 205 20 121-174 ψ%:45
F11 CL2 0.1-0.2 0.5-1 0.04 0.04 0.3-0.8 1-1.5 0.44-0.65 485 275 20 143-207 ψ%:30
F11 CL3 0.1-0.2 0.5-1 0.04 0.04 0.3-0.8 1-1.5 0.44-0.65 515 310 20 156-207 ψ%:30
F12 CL1 0.05-0.15 0.5 0.045 0.045 0.3-0.6 0.8-1.25 0.44-0.65 415 205 20 121-174 ψ%:45
F12 CL2 0.1-0.2 0.1-0.6 0.04 0.04 0.3-0.8 0.8-1.25 0.44-0.65 485 275 20 143-207 ψ%:30
F304 0.08 1 0.03 0.045 2 18-20 8-11 N:0.1 515 205 30 ψ%:50
F304H 0.04-0.1 1 0.03 0.045 2 18-20 8-11 515 205 30 ψ%:50
F304L 0.035 1 0.03 0.045 2 18-20 8-13 N:0.1 485 170 30 ψ%:50
F316L 0.035 1 0.03 0.045 2 16-18 10-15 2-3 N:0.1 485 170 30 ψ%:50
F317 0.08 1 0.03 0.045 2 18-20 11-15 3-4 515 205 30 ψ%:50
F321 0.08 1 0.03 0.045 2 17-19 9-12 Ti:5C%-0.7 515 205 30 ψ%:50
F347 0.08 1 0.03 0.045 2 17-20 9-13 Ti:10C%-1.1 515 205 30 ψ%:50

ASTM A53/A53M

Steel No. Standard No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
B ASTM A53/A53M 0.3 0.045 0.05 1.2 0.4 0.4 0.15 V:0.08 415 240 See sdandard

ASTM A106

Steel No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
B 0.3 0.1min 0.035 0.035 0.29-1.06 0.4 0.4 0.15 V:0.08 415 240 22
C 0.35 0.1min 0.035 0.035 0.29-1.06 0.4 0.4 0.15 V:0.08 485 270 20

ASTM A312/A312M

Steel No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
TP304 0.08 0.75 0.03 0.04 2 18-20 8-11 515 205 35
TP304H 0.04-0.1 0.75 0.03 0.04 2 18-20 8-11 515 205 35
TP304L 0.035 0.75 0.03 0.04 2 18-20 8-13 485 170 35
TP316L 0.035 0.75 0.03 0.04 2 16-18 10-15 2-3 485 170 35
TP321 0.08 0.75 0.03 0.04 2 17-20 9-13 Ti:5C%-0.7 515 205 35

ASTM A515/A515M

Steel No. Type Chemical composition
C Si S P Mn Cr Ni Mo Other ób ós δ5 HB
60 0.24 0.13-0.45 0.035 0.035 0.98 415-550 220 25
65 0.28 0.13-0.45 0.035 0.035 0.98 450-585 240 23
70 0.31 0.13-0.45 0.035 0.035 1.3 485-620 260 21

Tensile Property For Part Standard

StandardGradeYield Strengh(Mpa)Tensile Strengh(Mpa)Hardness
MinMaxMinMaxMax
W860WPHY42290415
WPHY46320435
WPHY52360460
WPHY56390490
WPHY60415520
WPHY65450535
WPHY70485570
A234WPC210335
WPB245415
P11205380
P22205380
P5205415
P9205415
P91415585
P92440620

Fittings applications and markets

Pipe and pipe fittings go hand-in hand. Just as pipes are used for a variety of residential, public and industrial applications, so also the pipe fittings. No pipes can be connected without the use of proper fittings and flanges. Pipe fittings allow pipes to be installed and connected or joined where necessary and terminated in the right place.

Such as Oil and gas industries, Midstream, Shipbuilding, Power plants, Food plants, Pharmaceuticals, etc.

Pipe fittings include a wide range of products in various shapes, sizes and materials. With rapid developments in the field of industrial fittings and continuous research work in this industry, various new products are manufactured. Some fittings have certain special features so that they can be fabricated on different principles like hydraulics, pneumatic depending on the end usage. Fittings include a comprehensive range of products depending on various applications in which they are applied.

Fittings are used wherever liquids, gases, chemicals and other fluids are created, processed, transported, or used.

There is no end to applications of pipe fittings so long there is no end to the applications of pipes . While the list of piping applications continues to expand, its strength, flexibility, very good flow rates and high chemical resistance are qualities which are uniquely suited for the movement or transfer of liquids, steam, solids and air from one point to another.

With piping, pipe fittings have many other uses like as follows:

  • The transfer of extremely hazardous materials such as chemical and waste.
  • Protection of sensitive equipment from high pressures.
  • Protection from corrosion and other extreme weather conditions.
  • Resistance to household and industrial chemicals.

Considering the various purposes of pipe fittings, these pipe fittings are used in various industries like:

  • Chemical / Petrochemical
  • Municipal
  • Food, Beverage, and Dairy
  • Oil and Gas
  • Power
  • Process Instrumentation
  • Pulp and Paper
  • Semiconductor
  • Marine & dredging
  • Sanitation
  • Flanges Used in Piping Systems
  • Irrigation
  • Residential
  • Road & highway construction
  • Ventilation etc.

Important Points for selecting best carbon steel fittings

If you have a new industrial project which includes pipe installation, you would want to select best material for laying down the pipes, elbows, flanges etc. In this context it would be useful to keep in mind a few of the following points:

  • Evaluate the magnitude of the project
  • Understand the scale of the implementation
  • Enumerate the liquids or gases the pipes are going to carry
  • The desired age or longevity of the structure

These pointers will help u decide which metal to choose to lay down the pipes. Usually, steel is a popular choice, considering its characteristics. Additionally, in order to enhance the characteristics of steel, carbon or chrome is used. So, the carbon steel fittings become the perfect choice for industrial projects. The major benefits of using these carbon steel pipe fittings are:

  • Robustness to the product.
  • More the carbon, more the durability.
  • Improve the strength without losing the shape.
  • The proportion of carbon to steel can be morphed.
  • Rust resistant.

Also with carbon steel pipe fittings,There is a wide variety of flanges available in the market today. However, making the right choice of flange to the right project becomes critical ss per the project requirements.weld neck flanges are good choices, If the project demands high temperatures or sub zero temperatures.

This flange provides extra reinforcement.The flange fits perfectly into the internal diameter of the pipe and this helps to avoid all hitches in the flow of desired substances through the pipes.

Thus, having a good knowledge of pipes as well as flanges that suit the requirements of a particular project, help you to select better material. This choice is critical for the perfect implementation of the project and durability, effectiveness and longevity of the implementation.Additionally, using the right kind of pipes and flanges during project implementation helps the project to pass the quality, efficiency as well as safety parameters.

How a Butt Weld Fitting is Made?

Buttweld pipe fittings comprises of long radius elbow, concentric reducer, eccentric reducers and Tees etc. Butt weld stainless steel and carbon steel fittings are an important part of industrial piping system to change direction, branch off or to mechanically join equipment to the system. Buttweld fittings are sold in nominal pipe sizes with specified pipe schedule. BW fitting’s dimensions and tolerances are defined as per ASME standard B16.9.

A butt weld pipe fitting is made by the process of hot forming that includes bending and forming to shape. The starting material of butt weld fitting is a pipe that is cut to length, heated and molded into specific shapes by means of dies. Heat treatment is also done to remove residual stresses and obtain desired mechanical properties.

There are numerous processes for manufacturing butt weld fittings, several examples listed as follows.

TEES: Extrusion method

The hot-extrusion process consists of enclosing a piece of metal, heated to forging temperature, in a chamber called a “container” having a die at one end with an opening of the shape of the desired finished section, and applying pressure to the metal through the opposite end of the container.

ELBOWS: Mandrel method

There are numerous processes for manufacturing butt weld fittings, several examples listed as follows.

CAPS: Deep Drawing method

One of the most common manufacturing methods for caps, where plate is cut out in a circle and formed by deep drawing.

The two principal reasons for perform metal forming at elevated temperatures (hot working) are to reduce the forming loads through the reduction of the resistance of the steel to deformation, and to develop preferred metallurgical structures for strength and ductility of the finish products. The most appropriate manufacturing method of a product will be decided with consideration of its material, sizes, shape, use, standards and other properties.

DOWNLOAD STANDARD

Even welding and smooth weld line, can be substitute for seamless tube after drawing and cold rolling.

This Standard covers overall dimensions, tolerances, ratings, testing, and markings for wrought factory-made buttwelding fittings in sizes NPS 1 ⁄ 2 through 48 (DN 15 through 1200).

ASTM A420 Standard Specification

ASTM A420/A420M-07 Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service.

ASTM A234/ SA234M Standard specification for pipe fittings of wrought carbon steel and alloy steel for moderate and high temperature service.

These fittings are for use in pressure piping and in pressure vessel fabrication for service at moderate and elevated temperatures.

The manufacture and installation of pipe fittings is tightly regulated by various standards and codes.

Who decides on standards and specifications for butt weld fittings ?

Manufacturers of butt weld pipe fittings have to meet specifications and requirements of many organizations, to assure quality, compatibility and performance of their products.

Key national and international standards organizations focus on materials and end-user industries, including American Society for Testing and Materials (ASTM), American Society of Mechanical Engineers (ASME), International Organization for Standardization (ISO), Norway’s NORSOK, …

Some international organizations also focus on quality standards across all industries, such as International Organization for Standardization (ISO).
Large industrial end-users also have their own programs to certify individual manufacturing plants as meeting their criteria to be listed on their Approved Manufacturers List (AML).

All these certifications and approvals are valid for a specific period, and must be renewed regularly.

Types of pipe fitting standards:

Some widely used pipe fitting standards are as follows:

ASME: American Society for Mechanical Engineers

This is one of the reputed organizations in the world developing codes and standards. The schedule number for pipe fitting starts from ASME/ANSI B16.

The schedule number for pipe fitting starts from ASME/ANSI B16. The various classifications of ASME/ANSI B16 standards for different pipe fittings are as follows:

  • ASME/ANSI B16.1 – 1998 – Cast Iron Pipe Flanges and Flanged Fittings
  • ASME/ANSI B16.3 – 1998 – Malleable Iron Threaded Fittings
  • ASME/ANSI B16.4 – 1998 – Cast Iron Threaded Fittings
  • ASME/ANSI B16.5 – 1996 – Pipe Flanges and Flanged Fittings
  • ASME/ANSI B16.11 – 2001 – Forged Steel Fittings, Socket-Welding and Threaded
  • ASME/ANSI B16.14 – 1991 – Ferrous Pipe Plugs, Bushings and Locknuts with Pipe Threads
  • ASME/ANSI B16.15 – 1985 (R1994) – Cast Bronze Threaded Fittings
  • ASME/ANSI B16.25 – 1997 – Buttwelding Ends
  • ASME/ANSI B16.36 – 1996 – Orifice Flanges etc.



ASTM International:
American Society for Testing and Materials

This is one of the largest voluntary standards development organizations in the world. It was originally known as the American Society for Testing and Materials (ASTM).

  • ASTM A105 / A105M – Specification for Carbon Steel Forgings for Piping Applications
  • ASTM A234 / A234M – Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
  • ASTM A403 / A403M – Specification for Wrought Austenitic Stainless Steel Piping Fittings
  • ASTM A420 / A420M – Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service

AWWA
American Water Works Association

AWWA About – Established in 1881, the American Water Works Association is the largest nonprofit, scientific and educational association dedicated to managing and treating water, the world’s most important resource.

  • AWWA C110 – Ductile-Iron and Gray-Iron Fittings, 3 Inch Through 48 Inch (75 mm Through 1200 mm), for Water and Other Liquids
  • AWWA C208 – Dimensions for Fabricated Steel Water Pipe Fittings

ANSI:
The American National Standards Institute

The American National Standards Institute
ANSI is a private, non-profit organization. Its main function is to administer and coordinate the U.S. voluntary standardization and conformity assessment system. It provides a forum for development of American national standards. ANSI assigns “schedule numbers”. These numbers classify wall thicknesses for different pressure uses.


MSS STANDARDS
Manufacturers Standardization Society

The Manufacturers Standardization Society (MSS) of the Valve and Fittings Industry is a non-profit technical association organized for development and improvement of industry, national and international codes and standards for: Valves, Valve Actuators, Valve Modification, Pipe Fittings, Pipe Hangers, Pipe Supports, Flanges and Associated Seals

  • MSS SP-43 – Wrought Stainless Steel Butt-Welding Fittings Including Reference to Other Corrosion Resistant Materials
  • MSS SP-75 – Specifications for High Test Wrought Buttwelding Fittings
  • MSS SP-73 – Brazing Joints for Copper and Copper Alloy Pressure Fittings
  • MSS SP-83 – Class 3000 Steel Pipe Unions, Socket-Welding and Threaded
  • MSS SP-97 – Integrally Reinforced Forged Branch Outlet Fittings — Socket Welding, Threaded, and Buttwelding Ends
  • MSS SP-106 – Cast Copper Alloy Flanges and Flanged Fittings Class 125,150, and 300
  • MSS SP-119 – Factory-Made Wrought Belled End Socket Welding Fittings

Difference between “Standard” and “Codes”:

Piping codes imply the requirements of design, fabrication, use of materials, tests and inspection of various pipe and piping system. It has a limited jurisdiction defined by the code. On the other hand, piping standards imply application design and construction rules and requirements for pipe fittings like adapters, flanges, sleeves, elbows, union, tees, valves etc. Like a code, it also has a limited scope defined by the standard.


Factors affecting standards:

“Standards” on pipe fittings are based on certain factors like as follows:

  • Pressure-temperature ratings
  • Size
  • Design
  • Coatings
  • Materials
  • Marking
  • End connections
  • Dimensions and tolerances
  • Threading
  • Pattern taper etc.

BSP:
British Standard Pipe

BSP is the U.K. standard for pipe fittings. This refers to a family of standard screw thread types for interconnecting and sealing pipe ends by mating an external (male) with an internal (female) thread. This has been adopted internationally. It is also known as British Standard Pipe Taper threads (BSPT )or British Standard Pipe Parallel (Straight) threads (BSPP ). While the BSPT achieves pressure tight joints by the threads alone, the BSPP requires a sealing ring.


JIS:
Japanese Industrial Standards

This is the Japanese industrial standards or the standards used for industrial activities in Japan for pipe, tube and fittings and published through Japanese Standards Associations.


NPT:
National Pipe Thread

National Pipe Thread is a U.S. standard straight (NPS) threads or for tapered (NPT) threads. This is the most popular US standard for pipe fittings. NPT fittings are based on the internal diameter (ID) of the pipe fitting.

BOLTS & NUTS

We are manufacturer of Flange bolts & Nuts and supply high quality

  • A193 = This specification covers alloy and stainless steel bolting material for pressure vessels, Valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications.
  • A320 = Standard Specification for Alloy-Steel and Stainless Steel Bolting Materials for Low-Temperature Service.
  • A194 = Standard specification for nuts in many different material types.

AN:
Here, “A” stands for Army and “N” stands for Navy

The AN standard was originally designed for the U.S. Military. Whenever, a pipe fitting is AN fittings, it means that the fittings are measured on the outside diameter of the fittings, that is, in 1/16 inch increments.

For example, an AN 4 fitting means a fitting with an external diameter of approximately 4/16″ or ¼”. It is to be noted that approximation is important because AN external diameter is not a direct fit with an equivalent NPT thread.

Dash (-) size

Dash size is the standard used to refer to the inside diameter of a hose. This indicates the size by a two digit number which represents the relative ID in sixteenths of an inch. This is also used interchangeably with AN fittings. For example, a Dash “8” fitting means an AN 8 fitting.

ISO:
International Organization for Standardization

ISO is the industrial pipe, tube and fittings standards and specifications from the International Organization for Standardization. ISO standards are numbered. They have format as follows:

“ISO[/IEC] [IS] nnnnn[:yyyy] Title” where

  • nnnnn: standard number
  • yyyy: year published, and
  • Title: describes the subject

A standard hose guide is given

Hose Size In Nominal ID Inch Dash Size Standard Dash Size
1/4 3/16 -04
3/8 5/16 -06
1/2 13/32 -08
3/4 5/8 -12
1 7/8 -16
1 ½
1 ¼ 1 1/8 -20

Flanges: Ratings in Classes and Pressure Numbers (PN)

Flange Class 150 300 600 900 1500 2500
Flange Pressure Number, PN 20 50 100 150 250 420

A standard hose guide is given below:

Hose Size In Nominal ID Inch Dash Size Standard Dash Size
1/4 3/16 -04
3/8 5/16 -06
1/2 13/32 -08
3/4 5/8 -12
1 7/8 -16
1 ½
1 ¼ 1 1/8 -20

ISO: International Organization for Standardization
ISO is the industrial pipe, tube and fittings standards and specifications from the International Organization for Standardization. ISO standards are numbered. They have format as follows:

“ISO[/IEC] [IS] nnnnn[:yyyy] Title” where

  • nnnnn: standard number
  • yyyy: year published, and
  • Title: describes the subject

JIS: Japanese Industrial Standards

This is the Japanese industrial standards or the standards used for industrial activities in Japan for pipe, tube and fittings and published through Japanese Standards Associations.

NPT: National Pipe Thread

National Pipe Thread is a U.S. standard straight (NPS) threads or for tapered (NPT) threads. This is the most popular US standard for pipe fittings. NPT fittings are based on the internal diameter (ID) of the pipe fitting.

What is an MTR ?

Material Test Reports (MTRs) are provided by manufacturers to certify physical properties and metal grade or alloy for each fitting, flange, pipe, or valve. This MTR is essential for demanding applications (pressure, temperature, corrosion, abrasion,…)

Buttweld Pipe Fitting Specification & Standards

Welded pipe fittings are made as per ASME spec B16.9. ASME B16.9 covers factory made wrought steel butwelding fittings in sizes 1/2″ to 48″. This standard however does not cover low pressure corrosion resistant buttwelding fittings.

ASTM A234 WPB is the Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service.

Specifications 

A234 WPB is the most common material used for carbon steel butt welded fittings.

  • ASTM: A234 WPB
  • ASME: B16.9, B.11
  • NACE: MRO175
  • MSS: SP-83, SP-95

WPB Chemical Composition(%)

Grade

C

Mn

P

S

Si

Cr

Mo

Ni

Cu

Others

max

max

WPB

0.3

0.29-1.06

0.05

0.058

0.1

0.4

0.15

0.4

0.4

V 0.08

(1,2,3,4,5)

max

min

max

max

max

max

max

  • Fittings made from bar or plate may have 0.35 max carbon.
  • Fittings made from forgings may have 0.35 max Carbon and 0.35 max Silicon with no min.
  • For each reduction of 0.01% below the specified Carbon maximum, an increase of 0.06% Manganese above the specified maximum will be permitted, up to a maximum of 1.35%.
  • The sum of Copper, Nickel, Niobium, and Molybdenum shall not exceed 1.00%.
  • The sum of Niobium and Molybdenum shall not exceed 0.32%.

In ASME/ANSI standard, butt welding pipe fittings technical requirements are specified in the standard ASME/ANSI B16.9, including all the types of pipe fittings. In EN standard, it is EN10253 standard for the butt welding pipe fittings.

In JIS, DIN, Ghost standard, different type of butt welding fittings are in different standard number. For example, JIS B2311, B2312, B2313  or GOST 17373, GOST 17375, GOST 17376, GOST 17378 etc.

There are also some other standards about butt welding pipe fittings like:

  • MSS SP-43
  • MSS SP-75
  • ASME B16.49