What are buttweld fittings in piping? Buttweld fittings are pipe fittings used to change the pathway of a pipeline (elbows), reduce/increase the pipe bore size (reducers), branch (tees, cross) or blind a pipeline (butt weld cap). ASME B16.9 (and MSS-SP 43) Buttweld fittings are used for piping systems above 2 inches in diameter, whereas socket weld and threaded fittings are used for smaller size pipes (ASME B16.11).
BUTTWELD FITTINGS IN PIPING
Buttweld fittings are available in multiple shapes (elbows, tees, reducers, crosses, caps, stub ends), material grades (carbon, high-yield carbon, low-alloy, stainless, duplex, and nickel alloys), and dimensions (2 to 24 inches in seamless execution, and welded for larger pipe sizes).
The key specifications for buttweld fittings are the ASME B16.9 (carbon and alloy fittings) and the MSS SP 43 (that integrates ASME B16.9 for stainless steel, duplex, and nickel alloy BW fittings).
Butt welding fittings have the following benefits
- allow strong, and leak-proof, piping connections
- minimize pressure drops and the turbulence inside the pipeline
- have a long service life
- are rather cheap to purchase and deploy
For piping systems below 2 inches in diameter, socket weld and threaded (forged) fittings are generally used (ASME B16.11).
BUTTWELD ELBOW 45/90/180 DEG.
ASME B16.9 buttweld elbows are manufactured in a wide range of dimensions (combinations of outside diameter and wall thickness) to fit ASME B36.10 and ASME B36.19 carbon, alloy and stainless steel pipes of any size between 2 and 48 inches (and above).
Buttweld elbows below 24 inches in diameter are produced by cutting, heating and bending seamless steel pipes; pipe elbows of larger sizes are manufactured, instead, from welded pipes or steel plates.
The three most common types of elbows in piping are the 45, 90, and 180 degrees (or return elbow), as shown in the image:
Some special types of pipe elbows are:
- reducing elbow: a pipe connector with an inlet and an outlet in two different bore sizes is used instead of the combination of a standard elbow and concentric reducer.
- mitered elbow: large size elbow assembled by joining steel plates
SHORT VS LONG RADIUS ELBOW
The center to face distance of a long radius pipe elbow is always 1.5 times the nominal pipe size, whereas, for a short radius pipe elbow, the center to face distance is equal to the nominal pipe size.
Example:
- For a 4 inches long radius (LR) butt weld elbow, the center to face distance is 4 x 25.4 x 1.5 = 152.4 mm;
- For a short radius butt weld elbow, the center to face distance is instead 4 x 25.4 x 1 = 101.6 mm. Short radius pipe elbows are available only for the 90 and 180-degree configuration (and not for the 45 degrees); instead, long radius elbows are available for all degrees.
. 
PIPE ELBOW MANUFACTURING PROCESS
Buttweld elbows 45 and 90 degrees can be manufactured in different ways, the main ones are the “mandrel process” and the “cold forming” (other methods are the elliptical forming and the double-seam welding method).
Mandrel Process
Cold forming
PIPE BENDS
A pipe bend is a generic term to indicate a fittings that changes the direction of the piping system (technically, elbows are pipe bends too but of a standardized type in terms of angle degree and direction). The term “pipe bend” refers to a fitting that offsets the direction of the pipe works, without specifying the actual degree and direction.
Pipe bends are manufacturing by twisting a pipe or a tube using a bending machine, with an hot or a cold forming process. Pipe bends are economical ways of making pipe works layouts decreasing the number of other pipe fittings used.
BUTTWELD TEE
EQUAL TEE
An equal tee, otherwise called straight tee, is a buttweld fitting used to branch a pipeline, or any other pipework, at 90 degrees.
A pipe tee is defined “equal” when the bore size at the run and branch sides have the same diameter. An equal tee is, therefore, used to connect two pipes of the same nominal diameter.
Equal tees are available in sizes from half an inch to 48 inches (or larger) and in seamless and welded execution (seamless up to 24 inches, welded for tee sizes above 24 inches).
Buttweld tees are manufactured according to ASME B16.9 (carbon and alloy) and MSS SP 43 (stainless steel and nickel alloy).
REDUCING TEE
A reducing tee features a smaller bore size at the branched pipe side (generally 2/3 sizes smaller).
In case a larger bore size reduction is necessary, then a reinforced branch connection (such as a Weldolet) shall be preferred to prevent turbulence and have a smoother flow reduction.
The standard dimensions and tolerances of equal and reducing pipe tees are covered by the ASME B16.19 specification (carbon and alloy steel) and by the MSS SP 43 spec (for stainless steel and nickel alloys tees).
BARRED TEE
A barred tee is a special type of (equal) tee used for pigging operations (reducing barred tees do not exist, as the pig would not pass through the reduced area anyway).
A barred tee features a welded restriction on the branch pipe side that prevents the pig from flowing from the run pipe into the branched pipe.
Such barred restriction is welded on the internal side of the fitting and looks like a steel cage.
PIPE TEE MANUFACTURING PROCESS
Cold forming is the most used manufacturing process for seamless buttweld tees, as illustrated below. Other methods are the single or double seam welding process.
BUTTWELD CROSS
A Butt weld cross fitting is used when a double branch at 90 degrees is required, which is a rather rare need.
ASME B16.9 and MSS SP43 define the pipe cross dimensions and tolerance. There are no specific limitations in terms of available sizes and schedules for butt weld crosses.
BUTTWELD REDUCERS
CONCENTRIC REDUCER
The open ends of a concentric reducer are aligned and centered one to the other. Generally, this type of pipe reducer is used to modify the bore size of the pipeline by two (maximum three) measures, to avoid an excessive pressure drop in the pipeline.
If a larger reduction is needed, then a sequence of reducers shall be used to have a smooth and gradual adjustment of the pipeline bore size (vs. a drastic change).
For small bore size reductions, reducing flanges may be an alternative to buttweld reducers.
ECCENTRIC REDUCER
The open ends of an eccentric reducer are in an “offset” position one to the other.
Eccentric reducers are used, generally, for pipelines installed in a horizontal position (whereas concentric reducers are used for pipelines installed vertically or for the inlets of suction pumps, as top flat eccentric reducers).
TOP AND BOTTOM FLAT ECCENTRIC REDUCER
CONCENTRIC VS ECCENTRIC REDUCER
The key difference between concentric vs eccentric reducer is the centricity of the inlet vs. the outlet of the fitting, which is perfect for a concentric reducer and offset of an eccentric reducer.
BW REDUCER MANUFACTURING PROCESS
Cold forming is the most common manufacturing process for seamless eccentric/concentric reducers (welded reducers are produced with the single or double seam weld process):
PIPE CAP
A buttweld pipe cap is used to blind or isolate the pipeline, permanently or temporarily (for example during the execution of maintenance and reparation works).
Buttweld pipe caps are manufactured using steel plates for most sizes and materials. The shape of a pipe cap is ellipsoidal and conforms to the requirements set by the «ASME Boiler and Pressure Vessel» code.
PIPE CAP MANUFACTURING PROCESS
The manufacturing process of caps starts from steel plates that are cut and shaped with a cold forming procedure:
SEAMLESS VS WELDED BW FITTINGS
Butt weld fittings are available in seamless and welded execution (seamless for bore sizes below 24 inches, welded for sizes above 24 inches).
Seamless buttweld fittings have no seam welds and are therefore considered superior to welded BW fittings (a weld is always a weak point on the metal, prone to corrosion).
Seamless BW fittings are manufactured by cutting, heating and shaping seamless pipes into desired forms. Welded buttweld fittings have one, two or more welds, depending on the dimension, the type of fitting and the manufacturing process adopted by the mill.
BUTT WELD FITTINGS MANUFACTURERS
- Awaji
- APP/CB&I
- Bassi Luigi
- Canadoil
- Close Bend
- Colonial Machine
- Erne Fittings
- Ezeflow
- Hackney-Ladish
- Houston Pipe Benders
- IRC Spa
- Mills Iron Works
- OMR Raccordi (Officine Meccaniche Righi)
- Raccortubi
- Shanghai Gateway Fittings Co
- Steel Forgings
- Sungkwang Bend
- Tectubi
- Tenaris
- TK Bend
- Tube Forgings of America
EU Origin
Factory Prices
Top Quality
15 Responses
I’m willing to tell you that I appreciated your article, it’s useful for me, and help me have a good sense.
Retrouvez les derniers essais automobiles.
Dear Sir,
Please share your best prices for the following:
Item End user code Materials Qty: Origin
1 Carbon steel Elbow 10″ 45 degree SCH 40 10
2 Carbon steel Elbow 10″ 90 degree SCH 40 20
3 Carbon steel Elbow 12″ 45 degree SCH 40 8
4 Carbon steel Elbow 12″ 90 degree SCH 40 20
5 Carbon steel Elbow 14″ 45 degree SCH 40 8
6 Carbon steel Elbow 14″ 90 degree SCH 40 10
7 Carbon steel Elbow 16″ 45 degree SCH 40 8
8 Carbon steel Elbow 16″ 90 degree SCH 40 10
9 Carbon steel Elbow 18″ 45 degree SCH 40 8
10 Carbon steel Elbow 18″ 90 degree SCH 40 10
11 Carbon steel Elbow 20″ 45 degree SCH 40 8
12 Carbon steel Elbow 20″ 90 degree SCH 40 10
13 Carbon steel Elbow 24″ 45 degree SCH 40 8
14 Carbon steel Elbow 24″ 90 degree SCH 40 10
15 Carbon steel Elbow 28″ 45 degree SCH 40 8
16 Carbon steel Elbow 28″ 90 degree SCH 40 10
17 Carbon steel Elbow 2″ 45 degree SCH 40 50
18 Carbon steel Elbow2″ 90 degree SCH 40 100
19 Carbon steel Elbow 3″ 45 degree SCH 40 50
20 Carbon steel Elbow 3″ 90 degree SCH 40 100
21 Carbon steel Elbow 4″ 45 degree SCH 40 50
22 Carbon steel Elbow 4″ 90 degree SCH 40 100
23 Carbon steel Elbow 5″ 45 degree SCH 40 10
24 Carbon steel Elbow 5″ 90 degree SCH 40 20
25 Carbon steel Elbow 6″ 45 degree SCH 40 25
26 Carbon steel Elbow 6″ 90 degree SCH 40 50
27 Carbon steel Elbow 8″ 45 degree SCH 40 25
28 Carbon steel Elbow 8″ 90 degree SCH 40 50
Note:
1. Quotation as proforma invoice with details
2. Name & Origin of the manufacturer:
3. Product shall be from G.C.C, USA, UK, Canada, South Korea, Japan, European Country Of Origin
Union Countries, or Australia.
4. Material Test Certificate as per EN10204-3.1 (or) equivalent to be provided along with material delivery.
5. All items to be supply Black Carbon Steel Schedule 40 ASTM A53/A106, should be mentioned in your offer.
6. Total CFR Kuwait Shuwaikh port by sea price & Weight & volume
7. Delivery date to Kuwait port
8. Price validity – 90 days from 17/02/2021
Best regards,
Please contact me – [email protected]
Dear Sir,
Asalam wale kum bhaijaan
We Counting upon our excellent sourcing capabilities and rich industry experience, we, Bidasar Forge Industries, have become the foremost choice of a large number of buyers in the national market segment. we have scaled to the newer heights of success owing to our unrelenting efforts and dedication. In two years, we have been able to garner a vast clientele due to the impeccable quality standards of our range of Pipe Fittings. Today, we are well known as a renowned Exporters, Manufacturer, importer, Stockist, and supplier in this cut-throat industry. We are Manufacturing and importing a comprehensive array of Pipe Fittings (Buttweld Fittings, Flanges), Socket Weld Fittings, High-Pressure Fittings, and more.
All these products are at par with superior industrial standards and are widely accepted in various industrial segments. To ensure optimum quality, we procure our entire array from only well-established vendors of the industry. Moreover, our efficient team of procurement personnel makes sure that the products are sourced only after ensuring that those are free from defects. Also, our professionals keep in touch with Our labor Team and ensure that they follow industry recommended guidelines during the entire production process. Furthermore, to ascertain timely deliveries, we have developed a wide distribution network that spans across various locations in the country.
We are able to provide you Quality Material along with the Material Testing Certificate and if required by you we can arrange for Third party Inspection also.
The Products which we can provide for Carbon Steel are as follows:
Pipe Fittings:- Butt weld fittings Tee, Reducers, Caps. (Both seamless and Erw)
In view of the above, we hope you would consider us for requirements in Projects and maintenance by favouring us with your inquires and by registering our name in your approved Vendor’s List.
We once again thank your for your patronage and are looking forward for a long and mutually beneficial relationship with your esteemed organization.
Regards,
Naved Khilji
Bidasar Forge Industries
Direct No:-7339868084
Email:- [email protected]
Great content , it is very useful
This article is very informative
The bog is very informative and well written
Hello, thank you. We used your good article. Please visit my site and read about welding fitting.
very useful words
nice words
thanks for sharing
We specialised ourselves with the blessings of our beloved His Holiness Dr. Syedna Mohammed Burhanuddin Saheb (TUS) and under the guidance of Late S k Mohammed Bhai Calcuttawala, Late Siraj S k Mohammed Bhai Calcuttawala, Fakhruddin Siraj Calcuttawala offers Flanges, Butt Weld Fittings, Forged Fittings, Branch Outlets, G I Pipe Fittings, Pipe & Pipe Fittings, Valves, Boiler Mounting Pipe & Fittings Valves Under One Roof.
If you have any questions or need help, feel free to contact 9339842438.
Our Company was Established in the year 1968 as S. Nomi & Co. to form a house of Industrial products imported from the best sources on the Globe. Later as India developed its resources and steel & allied products, we established ourselves with these indigenous quality products.
9062842438
Email: [email protected]
Thank you for sharing this vital information with us and assisting us in meeting our goal. You may also go here.. Sanjay Metal India, Stainless Steel Flanges manufacturer, SS Pipe Fittings Manufacturers in India, SS Pipe Fittings Manufacturer, Stainless Steel Flanges Manufacturers, Stainless Steel Flanges Manufacturer in India
Good blog, learned a lot about buttweld fittings
Thank you for sharing this vital information with us and assisting us in meeting our goal. You may also go here.. Kalikund Steel & Engg Co, Stainless Steel Flanges manufacturer, SS Pipe Fittings Manufacturers in India, SS Pipe Fittings Manufacturer, Stainless Steel Flanges Manufacturers, Stainless Steel Flanges Manufacturer in India
Thank you for sharing this pipe fitting information with us it is very helpful for us. You may also go here.. Kalikund Steel & Engg Co, Stainless Steel Flanges manufacturer, SS Pipe Fittings Manufacturers in India, SS Pipe Fittings Manufacturer