Carbon steel return U bend

Carbon Steel Return U Bend is a type of pipe fitting used in piping systems that involves a change in the direction of the flow.

Carbon steel return U bend

Carbon Steel Return U Bends are used in various industries, including oil and gas, petrochemical, power generation, and many others. They are commonly used in heat exchangers, boilers, condensers, and other equipment that requires a change in the direction of the flow of fluids or gases.

A U return bend is a type of pipe fitting used to change the direction of fluid flow in a pipeline. It is called "U" because of its U-shaped configuration, which allows it to make a 180-degree turn in the direction of the flow. The U return bend can be made from various materials such as copper or plastic, depending on the application.

Similar to stainless steel U bends, carbon steel return U bends are designed to change the direction of fluid flow in a piping system by 180 degrees. They are commonly used in plumbing, HVAC, and industrial systems where high temperatures, pressures, and corrosive environments are not a concern.

Carbon steel U bends are available in different grades and sizes to suit various applications. The choice of carbon steel grade depends on factors such as the fluid being transported, the temperature and pressure conditions, and the specific requirements of the system.

During the selection and installation of a carbon steel return U bend, it is essential to ensure proper sealing and alignment to prevent leaks and ensure the efficient flow of fluids. It is also important to consider any applicable industry standards and codes that govern the use of carbon steel fittings in your specific application.

Carbon steel return U bend
Carbon steel return U bend
Carbon steel return U bend
Carbon steel return U bend
Carbon steel return U bend

Size

The bend is used to change the direction of run of pipe.it advantage is can matach long distance transition requirements,so it is commonly that bends dimension according to customer design.

Constants for Pipe Bends:

Formula:L = R x BL = Length of pipe requiredR = Radius of bendB = Constant from table used to find “L”L =30 x 1.5705 =47.115 in.or 47-1/8”

Standards accord to:

  • ASME B16.9
  • ASME B16.28
  • ANSI/ASME B16.25
  • MSS SP-97

Pressure: SCH5 to SCH160

Bending radius(R): R=3D, 5D, 7D and 12D
Bending angle (θ):15°, 30°, 45°, 60°, 90°, 135°, 180°

Outer diamete(D): D≤1800mm
Wall thickness(T): T≤120mm
Straight Length (L): The length between two ends general from 300mm-1500mm

Example: Find the length of pipe required to make a 90 bend with a radius of 30"

Pipe bend design
Nominal pipe Outside Diameter at Bevel Center to End
DN size D1 D2 C M
Series A Series B Series A Series B
20×15 26.9 25 21.3 18 29 29
25×20 33.7 32 26.9 25 38 38
25×15 33.7 32 21.3 18 38 38
32×25 42.4 38 33.7 32 48 48
32×20 42.4 38 26.9 25 48 48
32×15 42.4 38 21.3 18 48 48
40×32 48.3 45 42.4 38 57 57
40×25 48.3 45 33.7 32 57 57
40×20 48.3 45 26.7 25 57 57
40×15 48.3 45 21.3 18 57 57
50×40 60.3 57 48.3 45 64 60
50×32 60.3 57 42.4 38 64 57
50×25 60.3 57 33.7 32 64 51
50×20 60.3 57 26.9 25 64 44
65×50 76.1(73) 76 60.3 57 76 70
65×40 76.1(73) 76 48.3 45 76 67
65×32 76.1(73) 76 42.4 38 76 64
65×25 76.1(73) 76 33.7 32 76 57
80×65 88.9 89 76.1(73) 76 86 83
80×50 88.9 89 60.3 57 86 76
80×40 88.9 89 48.3 45 86 73
80×32 88.9 89 42.4 38 86 70
90×80 101.6 - 88.9 - 95 92
90×65 101.6 - 76.1(73) - 95 89
90×50 101.6 - 60.3 - 95 83
90×40 101.6 - 48.3 - 95 79
100×90 114.3 - 101.6 - 105 102
100×80 114.3 108 88.9 89 105 98
100×65 114.3 108 76.1(73) 76 105 95
100×50 114.3 108 60.3 57 105 89
100×40 114.3 108 48.3 45 105 86
125×100 139.7 133 114.3 108 124 117
125×90 139.7 - 101.6 - 124 114
125×80 139.7 133 88.9 89 124 111
125×65 139.7 133 76.1(73) 76 124 108
125×50 133 60.3 57 124 105
150×125 168.3 159 139.7 133 143 137
150×100 168.3 159 114.3 108 143 130
150×90 168.3 - 101.6 - 143 127
150×80 168.3 159 88.9 89 143 124
150×65 168.3 159 76.1(73) 76 143 121
200×150 219.1 219 168.3 159 178 168
200×125 219.1 219 139.7 133 178 162
200×100 219.1 219 114.3 108 178 156
200×90 219.1 - 101.6 - 178 152
200×200 273 273 219.1 219 216 208
200×150 273 273 168.3 159 216 194
200×125 273 273 139.7 133 216 191
200×100 273 273 114.3 108 216 184
300×250 323.9 325 273 273 254 241
300×200 323.9 325 219.1 219 254 229
300×150 323.9 325 168.3 159 254 219
300×125 323.9 325 139.7 133 254 216
350×300 355.6 377 323.9 325 279 270
350×250 355.6 377 273 273 279 257
350×200 355.6 377 219.1 219 279 248
350×150 355.6 377 168.3 159 279 238
400×350 406.4 426 355.6 377 305 305
400×300 406.4 426 323.9 325 305 295
400×250 406.4 426 273 273 305 283
400×200 406.4 426 219.1 219 305 273
400×150 406.4 426 168.3 159 305 264
450×400 457.2 478 406.4 426 343 330
450×350 457.2 478 355.6 377 343 330
450×300 457.2 478 323.9 325 343 321
450×250 457.2 478 273 273 343 308
450×200 457.2 478 219.1 219 343 298
500×450 508 529 457.2 478 381 368
500×100 508 529 406.4 426 381 356
500×350 508 529 355.6 377 381 356
500×300 508 529 323.9 325 381 346
500×250 508 529 273 273 381 333
500×200 508 529 219.1 219 381 324
550×500 559 - 508 - 419 406
550×450 559 - 457 - 419 394
550×400 559 - 406 - 419 381
600×550 610 - 559 - 432 432
600×550 610 630 508 530 432 432
600×450 610 630 457 480 432 419
650×600 660 - 610 - 495 483
650×550 660 - 559 - 495 470
650×500 660 - 508 - 495 457
700×650 711 - 660 - 521 521
700×600 711 720 610 630 521 508
700×550 711 - 559 - 521 495
750×700 762 - 711 - 559 546
750×650 762 - 660 - 559 546
750×600 762 - 610 - 559 533
800×750 813 - 762 - 597 584
800×700 813 820 711 720 597 572
800×650 813 - 660 - 597 572
850×800 864 - 813 - 635 622
850×750 864 - 762 - 635 610
850×700 864 - 711 - 635 597
900×850 914 - 864 - 673 660
900×800 914 920 813 820 673 648
900×750 914 - 762 - 673 635
950×900 965 - 914 - 711 711
950×850 965 - 864 - 711 698
950×800 965 - 813 - 711 686
1000×950 1016 - 965 - 749 749
1000×900 1016 1020 914 920 749 737
1000×8500 1016 - 864 - 749 724
1000×1000 1067 - 1016 - 762 711
1050×950 1067 - 965 - 762 711
1050×900 1067 - 914 - 762 711
1100×1050 1118 - 1067 - 813 762
1100×1000 1118 1120 1016 1020 813 749
1100×950 1118 - 965 - 813 737
1150×1100 1168 - 1118 - 851 800
1150×1050 1168 - 1067 - 851 787
1150×1000 1168 - 1016 - 851 775
1200×1150 1220 - 1168 - 889 838
1200×1100 1220 1220 1118 1120 889 838
1200×1050 1220 - 1067 - 889 813

Reference

Just before the final delivery, our merchandise are stringently checked by a team of quality analyzers on varied parameters, which guarantee their flawlessness and durability. In addition, clients can avail these goods from us at competitive rates.

ASTM

JIS

EURO

FAQ FAQ

Pipe fittings are necessary to join together pipes, or to change the direction of an existing pipe. Pipes and pipe fittings are made of a variety of materials, depending on the fluid or gas being transported. Most pipe fittings tend to be either threaded or able to slip over the pipes they connect. Whether you are using steel pipes of PVC pipes, a chemical solvent is required to create a seal between the pipe and the fittings.

Measure the required length of the pipe to be installed, keeping in mind the extra length required where the pipe will be inserted into the fitting. Mark this length on the pipe.

How to Calculate a Pipe Bend?

Pipe fittings are necessary to join together pipes, or to change the direction of an existing pipe. Pipes and pipe fittings are made of a variety of materials, depending on the fluid or gas being transported. Most pipe fittings tend to be either threaded or able to slip over the pipes they connect. Whether you are using steel pipes of PVC pipes, a chemical solvent is required to create a seal between the pipe and the fittings.

Measure the required length of the pipe to be installed, keeping in mind the extra length required where the pipe will be inserted into the fitting. Mark this length on the pipe.

Bevelled Ends

The ends of all buttweld fittings are bevelled, exceeding wall thickness 4 mm for austenitic stainless steel, or 5 mm for ferritic stainless steel. The shape of the bevel depending upon the actual wall thickness. This bevelled ends are needed to be able to make a “Butt weld”.

Welding Bevel acc.to ASME / ANSI B16.9 and ASME / ANSI B16.28

ASME B16.25 covers the preparation of buttwelding ends of piping components to be joined into a piping system by welding. It includes requirements for welding bevels, for external and internal shaping of heavy-wall components, and for preparation of internal ends (including dimensions and dimensional tolerances).

Beveld end

Our in-hourse R&D team developed bevel ends equipment are good using in thickness 2mm to 20mm pipe fittings, guarantee high efficiency and high quality.

These weld edge preparation requirements are also incorporated into the ASME standards (e.g., B16.9, B16.5, B16.34).

ASME B16.25 (BUTT WELD ENDS)

ASME B16.25 sets standards for the preparation of the ends of components that need to be welded together.

Cut square or slight chamfer, at manufacturer’s option for :

Buttweld Fittings general

A pipe fitting is defined as a part used in a piping system, for changing direction, branching or for change of pipe diameter, and which is mechanically joined to the system.

There are many different types of fittings and they are the same in all sizes and schedules as the pipe.

ASME / ANSI B16.9 dimension

ASME B16.9 Standard covers overall dimensions, tolerances,ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1⁄2 through NPS 48 (DN 15 through DN 1200).

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Nominal Outside Diameter 90° Elbows 45° Elbows 180° Returns
Pipe Size
Long Radius Short Radius Long Radius Long Radius
(inches) (mm) (inches) Center to Face Center to Face Center to Face Radius Center to Center Back to face
(inches) (inches) (inches) (inches) (inches) (inches)
1/2 21.3 0.84 1.5 5/8 2 1.875
3/4 26.7 1.05 1.125 7/16 2.25 1.6875
1 33.4 1.315 1.5 1 7/8 3 2.1875
1.25 42.2 1.66 1.875 1.25 1 3.75 2.75
1.5 48.3 1.9 2.25 1.5 1.125 3 4.5 3.25
2 60.3 2.375 3 2 1.375 4 6 4.1875
2.5 73 2.875 3.75 2.5 1.75 5 7.5 5.1875
3 88.9 3.5 4.5 3 2 6 9 6.25
3.5 101.6 4 5.25 3.5 2.25 7 10.5 7.25
4 114.3 4.5 6 4 2.5 8 12 8.25
5 141.3 5.563 7.5 5 3.125 10 15 10.3125
6 168.3 6.625 9 6 3.75 12 18 12.3125
8 219.1 8.625 12 8 5 12 24 16.3125
10 273.1 10.75 15 10 6.25 15 30 20.375
12 323.9 12.75 18 12 7.5 18 36 24.375

Tolerances of Welded Fittings

NOMINAL PIPE SIZE NPS ANGULARITY TOLERANCES ANGULARITY TOLERANCES
Size Off Angle Q Off Plane P
½ to 4 0.03 0.06
5 to 8 0.06 0.12
10 to 12 0.09 0.19
14 to 16 0.09 0.25
18 to 24 0.12 0.38
26 to 30 0.19 0.38
32 to 42 0.19 0.5
44 to 48 0.18 0.75

All dimensions are given in inches. Tolerances are equal plus and minus except as noted.

  1. Out-of-round is the sum of absolute values of plus and minus tolerance.
  2. This tolerance may not apply in localized areas of formed fittings where increased wall thickness is required to meet design requirements of ASME B16.9.
  3. The inside diameter and the nominal wall thicknesses at ends are to be specified by the purchaser.
  4. Unless otherwise specified by the purchaser, these tolerances apply to the nominal inside diameter, which equals the difference between the nominal outside diameter and twice the nominal wall thickness.

The ASME B16.9 pipe fittings can be used under the jurisdiction of the ASME Boiler & Pressure Vessel Code (BPVC) as well as the ASME Code for pressure piping. Referencing pressure ratings of flanges per ASME B16.5, they can be designated as Classes 150, 300, 600, 900, 1500 and 2500. The allowable pressure ratings for ASME B16.9 pipe fittings may be calculated as for straight seamless pipe of equivalent material in accordance with the rules established in the applicable sections of ASME B31 Code for pressure piping.

Design of Fittings

The design of butt welding pipe fittings made to ASME B16.9 shall be established by one of the following methods: (a) mathematical analyses contained in pressure vessel or piping codes; (b) proof testing; (c) experimental stress analysis with hydrostatic testing to validate experimental results; (d) detailed stress analysis with results evaluation.

Standard Marking

Generally, ASME B16.9 pipe fittings shall be marked to show the following details: “trademark + material grade + wall thickness + size + heat number”. For example, “M ASTM A234 WP5 SCH80 6″ 385“. When steel stamps are used, care shall be taken so that
the marking is not deep enough or sharp enough to cause cracks or to reduce the wall thickness of the fitting below the minimum allowed.

Material & Manufacture

The ASME B16.9 fittings may be made from an extensive range of mateirals covering (1) carbon and low-alloy steels in accordance with ASTM A234 and ASTM A420; (2) austenitic and duplex stainless steels in accordance with ASTM A403 and ASTM A815; (3) nickel alloys in accordance with ASTM B366; (4) aluminum alloys in accordance with ASTM B361; and (5) titanium alloys in accordance with ASTM B363.

ASME B16.9

Pipe Fittings Dimensions Tolerance as per ASME B16.9:

Sizes 1/2″ – 48″

  • ASME / ANSI B16.9 Butt Weld Elbow – Long Radius
  • ASME / ANSI B16.9 Butt Weld Elbow – Short Radius
  • ASME / ANSI B16.9 Butt Weld Reducing Elbow
  • ASME / ANSI B16.9 Butt Weld 45° Elbow
  • ASME / ANSI B16.9 Butt Weld Fabricated Tee
  • ASME / ANSI B16.9 Butt Weld Reducer
  • ASME / ANSI B16.9 Butt Weld Concentric Reducer
  • ASME / ANSI B16.9 Butt Weld Eccentric Reducer
  • ASME / ANSI B16.9 Butt Weld 3D Elbow
  • ASME / ANSI B16.9 Butt Weld Stub Ends
  • ASME / ANSI B16.9 Butt Weld Cross
  • ASME / ANSI B16.9 Butt Weld Reducing Cross
  • ASME / ANSI B16.9 Butt Weld Tees
  • ASME / ANSI B16.9 Butt Weld End Cap
  • ASME / ANSI B16.9 Butt Weld Coupling
  • ASME / ANSI B16.9 Butt Weld Pipe Nipple
  • ASME / ANSI B16.9 Butt Weld 5D Elbow
  • ASME / ANSI B16.9 Butt Welded Pipe Fittings
Reducer applications

Applications

A steel pipe reducer is a component used in the pipelines to reduce its size from large to small bore in accordance to the inner diameter.

The length of the reduction here is equal to an average of the smaller and larger pipe diameters. Here, the reducer can be used as a diffuser or a nozzle. The reducer helps in meeting the existing piping of varied sizes or hydraulic flow of the piping systems. The usage of a steel reducer is carried out in the chemical factories and power plants. It makes the piping system reliable and compact. It safeguards the piping system from any kind of adverse impact or thermal deformation. When it is on the pressure circle, it prevents from any type of leakage and is easy to install. The nickel or chrome coated reducers extends the product life, useful for high vapor lines, and prevents corrosion.

  • Pipe Reducer
  • Hydraulic system
  • Pneumatic system
  • Pharmaceutical fittings
  • Air brake fittings
  • Gas fittings
  • Refrigerant fittings
  • Changing the piping diameter
  • Handling the expansion, misalignment or vibration problem

Standard

Pipe fitting dimensions are in either metric or Standard English.

Because pipe fitting covers Pipe Fitting Dimensions several aspects, only the most common pipe fitting sizes can be given here. The most applied version is the 90° long radius and the 45° elbow, while the 90° short radius elbow is applied if there is too little space. The function of a 180° elbow is to change direction of flow through 180°. Both, the LR and the SR types have a center to center dimension double the matching 90° elbows. These fittings will generally be used in furnesses or other heating or cooling units.

Some of the standards that apply to buttwelded fittings are listed below. Many organizations such as ASME, ASTM, ISO, MSS, etc. have very well developed standards and specifications for buttwelded fittings. It is always up to the designer to ensure that they are following the applicable standard and company specification, if available, during the design process.

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 various classifications of ASME/ANSI B16 standards for different pipe fittings are as follows:

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).

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.

ANSI: 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

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:

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

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

General standard

Standard Specification
ASTM A234 Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service
ASTM A420 Standard Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service
ASTM A234 WPB ASTM A234 WPB refers to a specific grade of carbon steel pipe fittings, which are widely used in pressure piping and pressure vessel fabrication for service at moderate and elevated temperatures.
ASME B16.9 ASME B16.9 Standard covers overall dimensions, tolerances,ratings, testing, and markings for factory-made wrought buttwelding fittings in sizes NPS 1⁄2 through NPS 48 (DN 15 through DN 1200).
ASME B16.28 ASME B16.28 Standard covers ratings, overall dimensions, testing, tolerances, and markings for wrought carbon and alloy steel buttwelding short radius elbows and returns.
MSS SP-97 MSS SP-97 Standard Practice covers essential dimensions, finish, tolerances, testing, marking, material, and minimum strength requirements for 90 degree integrally reinforced forged branch outlet fittings of buttwelding, socket welding, and threaded types.
ASTM A403 Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings.

Wide variety for all areas of application

DIN EN ASME
St 35.8 I
St 35.8 III
15 Mo 3
13 CrMo 4 4
10 CrMo 9 10
St 35 N
St 52.0
St 52.4
P235GH-TC1
P235GH-TC2
16Mo3
13CrMo4-5
10CrMo9-10
X10CrMoVNb9-1
P215NL
P265NL
L360NB
L360NE
P355N
P355NL1
P355NH
WPB
WPL6
WPL3
WPHY 52
WP11
WP22
WP5
WP9
WP91
WP92

Delivery

Inspection

Visual Inspection is conducted on fittings to check any surface imperfections. Both fittings body and weld are checked for any visible surface imperfections such as dents, die marks, porosity, undercuts, etc. Acceptance as per applicable standard.

ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers
ASTM A234 WPB eccentric reducers

Packing

For packing of carbon steel flanges with painting,we would use the bubble wrap to protect the painting.For flanges without painting or oiled with long-term shipment,we would suggest client to use the anti-tarnish paper and plastic bag to prevent the rust.

【H】 Ceramic lined pipe

Ceramic lined pipe is made through self-propagating high-temperature synthesis (SHS) technique.

【H】 Cast basalt lined steel pipe

Cast basalt lined steel pipe is composed by lined with cast basalt pipe, outside steel pipe and cement mortar filling between the two layers.

【H】 Ceramic Tile Lined Pipes

Ceramic tile lined pipes have very uniform coating of specially formulated ceramic material that is affixed to the inner of the pipe.

【H】 Rare earth alloy wear-resistant pipe

The material of the rare earth alloy wear-resistant pipe is ZG40CrMnMoNiSiRe, which is also the grade of rare earth alloy steel.

【H】 Tubes Erosion Shields

Tubes Erosion Shields are used to protect boiler tubing from the highly erosive effects of high temperatures and pressures thereby greatly extending tube life.

【H】 ASTM A213 T91 Alloy Tube

The ASTM A213 T91 seamless tubes are primarily used for boiler, superheater, and heat-exchanger.