- PRODUCT DETAIL
Type: Reducing Elbow
Material: Grade 310S (UNS S31008)
Size: 6″ x 4″ (DN150 x DN100)
WT: SCH40S
Standard: ASME B16.9
Surface treatment: Mirror finish
Grade 310S stainless steel is superior than 304 or 309 stainless steel in most environments, because it has high nickel and chromium content. It has high corrosion resistance and strength in temperatures up to 1149°C (2100°F). The following datasheet gives more details about grade 310S stainless steel.
What is a reducing elbow?
Reducing elbow is a kind of pipe fitting that connects two different pipe diameters to do the steering.
Stamping reduced diameter elbow, it is the use of the same material as the pipe sheet with stamping die stamping into a half annular elbow, and then the two half annular elbow group for welding forming. Due to the different welding standards of all kinds of pipelines, semi-finished products are usually delivered according to the group of fixed points, and welded in field construction according to the grade of pipeline weld. Therefore, it is also called two-half welding elbow.
Purpose: Connecting two pipes with different diameters, making the pipe turn 90° while reducing the diameter. The production process adopted is to use the whole elbow drawing sliver shrinking process to produce. All it does is change the diameter of the pipe when making a 90 degree turn. It has the same function as the big and small heads, but the big and small heads cannot be used for steering.
According to the process: hot push elbow, stamping elbow, welding elbow, etc.
According to the material: carbon steel elbow, stainless steel elbow, alloy steel elbow, etc.
According to the specifications: there are short radius elbow, long radius elbow, 30° 45° 60° 90° and other different degrees of elbow.
Stamping reduced diameter elbow classification:
According to the material is divided into: carbon steel elbow, stainless steel stamping reduced diameter elbow, alloy steel stamping reduced diameter elbow.
According to the standard, it is divided into:
- China standard: Stamping reducing elbow, non-standard;
- International standard: German standard, Japanese standard, American standard, British standard stamping reduced diameter elbow. All it does is change the diameter of the pipe when making a 90 degree turn. It has the same function as the big and small heads, but the big and small heads cannot be used for steering. The price is about twice as high as the elbow of equal diameter. In some construction sites, an elbow and a small head are welded together instead of this product. Its material has carbon steel, stainless steel, alloy steel, titanium and titanium alloy, cast steel, etc.
Chemical composition % of grade 310 and 310S stainless steel
Chemical Composition |
310 |
310S |
Carbon |
0.25 max |
0.08 max |
Manganese |
2.00 max |
2.00 max |
Silicon |
1.50 max |
1.50 max |
Phosphorus |
0.045 max |
0.045 max |
Sulphur |
0.030 max |
0.030 max |
Chromium |
24.00 – 26.00 |
24.00 – 26.00 |
Nickel |
19.00 – 22.00 |
19.00 – 22.00 |
Mechanical properties of of grade 310/310S stainless steel
Mechanical Properties |
310/ 310S |
Grade 0.2 % Proof Stress MPa (min) |
205 |
Tensile Strength MPa (min) |
520 |
Elongation % (min) |
40 |
Hardness (HV) (max) |
225 |
Physical properties of grade 310/310S stainless steel
Properties |
at |
Value |
Unit |
Density |
|
8,000 |
Kg/m3 |
Electrical Conductivity |
25°C |
1.25 |
%IACS |
Electrical Resistivity |
25°C |
0.78 |
Micro ohm.m |
Modulus of Elasticity |
20°C |
200 |
GPa |
Shear Modulus |
20°C |
77 |
GPa |
Poisson’s Ratio |
20°C |
0.30 |
|
Melting Rnage |
|
1400-1450 |
°C |
Specific Heat |
|
500 |
J/kg.°C |
Relative Magnetic Permeability |
|
1.02 |
|
Thermal Conductivity |
100°C |
14.2 |
W/m.°C |
Coefficient of Expansion |
0-100°C |
15.9 |
/°C |
|
0-315°C |
16.2 |
/°C |
|
0-540°C |
17.0 |
/°C |
Fabrication of Grade 310/310S Stainless Steel
Fabrication Grades 310/310S are forged in the temperature range 975 – 1175°C. Heavy work is carried out down to 1050°Cand a light finish is applied to the bottom of the range. After forging annealing is recommended to relieve all stresses from the forging process. The alloys can be readily cold formed by standard methods and equipment.
Machinability of Grade 310/310S Stainless Steel
Machinability Grades 310/310S are similar in machinability to type 304. Work hardening can be a problem and it is normal to remove the work hardened layer by using slow speeds and heavy cuts, with sharp tools and good lubrication. Powerful machines and heavy, rigid tools are used.
Welding of Grade 310/310S Stainless Steel
Welding Grades 310/310S are welded with matching electrodes and filler metals. The alloys are readily welded by SMAW (manual), GMAW (MIG), GTAW (TIG) and SAW. Electrodes to AWS A5.4 E310-XX and A 5.22 E310T-X, and filler metal AWS A5.9 ER310 are used. Argon is shielding gas. Preheat and post heat are not required, but for corrosion service in liquids full post weld solution annealing treatment is essential. Pickling and passivation of the surface to remove high temperature oxides are essential to restore full aqueous corrosion resistance after welding. This treatment is not required for high temperature service, but welding slag should be thoroughly removed.
Heat Treatment of Grade 310/310S Stainless Steel
Heat Treatment Type 310/310S are solution annealed by heating to temperature range 1040 -1065°C, holding at temperature until thoroughly soaked, then water quenching.
Heat Resistance of Grade 310/310S Stainless Steel
Grades 310/310S have good resistance to oxidation in intermittent service in air up to 1035°Cand 1050°Cin continuous service. The grades are resistant to oxidation, sulphidation and carburisation.
Available Forms of Grade 310/310S Stainless Steel
Austral Wright Metals can supply these grades as plate, sheet and strip, bar and rod, seamless tube and pipe, welded tube and pipe, forgings and forging billet, tube and pipe fittings, wire. Corrosion Resistance Grade 310/310S is generally not used for corrosive liquid service, although the high chromium and nickel content give corrosion resistance superior to grade 304. The alloy does not contain molybdenum, so pitting resistance is quite poor. Grade 310/310S will be sensitised to intergranular corrosion after service at temperatures in range 550 – 800°C. Chloride stress corrosion cracking may take place in corrosive liquids containing chlorides at temperatures exceeding 100°C.
China Reducing Elbow Manufacturer www.steeljrv.com offers ASME B16.9 ASTM A403 WP310S 90 Degree Reducing Elbow LR, 6″ x 4″ SCH40S, Mirror Polishing.
Dimensions Butt Weld Reducing Elbows 90° LR ASME B16.9
NPS |
Outside Diameter |
Center |
|
|
Large |
Small |
|
4 – 3 |
114,3 |
88,9 |
152 |
4 – 2½ |
114,3 |
73 |
152 |
4 – 2 |
114,3 |
60,3 |
152 |
5 – 4 |
141,3 |
114,3 |
190 |
5 – 3½ |
141,3 |
101,6 |
190 |
5 – 3 |
141,3 |
88,9 |
190 |
5 – 2½ |
141,3 |
73 |
190 |
6 – 5 |
168,3 |
141,3 |
229 |
6 – 4 |
168,3 |
114,3 |
229 |
6 – 3½ |
168,3 |
101,6 |
229 |
6 – 3 |
168,3 |
88,9 |
229 |
8 – 6 |
219,1 |
168,3 |
305 |
8 – 5 |
219,1 |
141,3 |
305 |
8 – 4 |
219,1 |
114,3 |
305 |
NPS |
Outside Diameter |
Center |
|
|
Large |
Small |
|
10 – 8 |
273 |
219,1 |
381 |
10 – 6 |
273 |
168,3 |
381 |
10 – 5 |
273 |
141,3 |
381 |
12 – 10 |
323,8 |
273 |
457 |
12 – 8 |
323,8 |
219,1 |
457 |
12 – 6 |
323,8 |
168,3 |
457 |
14 – 12 |
355,6 |
323,8 |
533 |
14 – 10 |
355,6 |
273 |
533 |
14 – 8 |
355,6 |
219,1 |
533 |
16 – 14 |
406,4 |
355,6 |
610 |
16 – 12 |
406,4 |
323,8 |
610 |
16 – 10 |
406,4 |
273 |
610 |
18 – 16 |
457 |
406,4 |
686 |
NPS |
Large |
Small |
Center |
|
Outside Diameter |
|
|
18 – 14 |
457 |
355,6 |
686 |
18 – 12 |
457 |
323,8 |
686 |
18 – 10 |
457 |
273 |
686 |
20 – 18 |
508 |
457 |
762 |
20 – 16 |
508 |
406,4 |
762 |
20 – 14 |
508 |
355,6 |
762 |
20 – 12 |
508 |
323,8 |
762 |
20 – 10 |
508 |
273 |
762 |
24 – 22 |
610 |
559 |
914 |
24 – 20 |
610 |
508 |
914 |
24 – 18 |
610 |
457 |
914 |
24 – 16 |
610 |
406,4 |
914 |
24 – 14 |
610 |
355,6 |
914 |
24 – 12 |
610 |
323,8 |
914 |
Dim Tolerances of Butt Weld RED Elbows 90° LR ASME B16.9
Nominal Pipe Size | 1/2 to 2½ | 3 to 3½ | 4 |
Outside Diameter
at Bevel
|
+ 1.6
– 0.8
|
1.6 | 1.6 |
Inside Diameter
at End
|
0.8 | 1.6 | 1.6 |
Center to End LR (A) | 2 | 2 | 2 |
Nominal Pipe Size | 5 to 8 | 10 to 18 | 20 to 24 |
Outside Diameter
at Bevel
|
+ 2.4
– 1.6
|
+ 4
– 3.2
|
+ 6.4
– 4.8
|
Inside Diameter
at End
|
1.6 | 3.2 | 4.8 |
Center to End LR (A) | 2 | 2 | 2 |
Wall Thickness (t) | Not less than 87.5% of Nominal Wall Thickness |
Note:
- All dimensions are in millimeters unless otherwise indicated.
- Wall thickness (t) must be specified by customer.
Most elbows are available in short radius or long radius variants.
SHORT RADIUS ELBOWS
The short radius elbows have a center-to-end distance equal to the Nominal Pipe Size (NPS) in inches, while the long radius is 1.5 times the NPS in inches. Short elbows are widely available, and are typically used in pressurized systems.
LONG RADIUS ELBOWS
Long elbows are typically used in low-pressure gravity-fed systems and other applications where low turbulence and minimum deposition of entrained solids are of concern.

Difference between a pipe elbow and a pipe bend
- Pipe Bend is a generic term for any offset or change of direction in the piping. It is a vague term that also includes elbows.
- An elbow is an engineering term and they are classified as 90 deg or 45 deg, short or long radius.
- Pipe elbows have industrial standards and have limitations to size, bend radius and angle. The angles are usually 45 deg or 90 degrees. All others offsets are classified as pipe bends.
- Bends are generally made or fabricated as per the need of the piping; however elbows are pre fabricated and standard, and are available off the shelf.
- Bends are never sharp corners but elbows are. Pipe bending techniques have constraint as to how much material thinning can be allowed to safely contain the pressure of the fluid to be contained. As elbows are pre fabricated, cast or butt welded, they can be sharp like right angles and return elbows which are 180 degrees.
- Elbow is a standard fitting but bends are custom fabricated.
- In bends as the pipe is bent and there is no welding involved, there is less pipe friction and flow is smoother. In elbows, the welding can create some friction.
- All elbows are bends but all bends are not elbows.
- Bend has a larger radius then elbows.
- Generally the most basic difference is the radius of curvature. Elbows generally have radius of curvature between one to twice the diameter of the pipe. Bends have a radius of curvature more than twice the diameter.
Package of 90 Degree Reducing Elbow
- Wrapped polypropylene knitted bag on reducing elbow.
- Put plastic cap on each end of stainless steel elbow.
- Packed the 90 degree elbow into wooden case.
How to Guarantee the Quality of 90 Degree LR Reducing Elbow?
We will do strictly inspection as below step:
- Visual the surface of 90 degree reducing elbow body.
- Check the marking: “ASME B16.9 ASTM A403 WP310S 90 Degree Reducing Elbow LR 6″ x 4″ SCH40S Mirror Polishing″.
- Measure the dimensions. Such as diameter, thickness, height from center to end.
- Test material chemical composition of 90 degree reducing elbow.
How to Protect the Surface of 180 Degree Elbow?
- Hot Dipped Galvanized
- Cold Galvanized
- Black Primer
- PE Coated
How to calculation weight of elbow
In a piping system, the elbow is a pipe fitting that changes the direction of the pipe. According to the angle, there are 45 ° and 90 ° 180 ° three kinds of the most commonly used, according to the project also includes 60 ° and other non-normal angle elbow. Elbow materials are cast iron, stainless steel, alloy steel, malleable cast iron, carbon steel, nonferrous metals and plastics.
Elbow weight calculation formula:
Ring volume = 2X3.14X3.14 (r ^ 2) R
- r – radius circle
- R – radius of gyration of the ring
- Hollow tube ring volume = 2X3.14X3.14 ((r^2) – (r’^2)) R
- r’- circle radius of the inner circle
90,60,45 degree elbow (elbow), respectively corresponding to the volume of the hollow tube ring volume of 1/4, 1/6, 1/8.
The density of steel engineering calculations by weight 7.85 kg / dm, density X volume = weight (mass).
Note:
- 1. 180 ° elbow calculated by the table 2 times, 45 ° by 1/2;
- 2. R1.0DN elbow weight calculated according to Table 2/3;
- 3. The table does not list the weight of the wall thickness, preferably with the similar two weight calculation of the average;
- 4. 90 ° elbow calculation formula; 0.0387 * S (D-S) R / 1000 where S = wall thickness mm D = diameter mm R = bending radius mm.
Manufacturing process of the pipe elbow
Mandrel method (Hot Forming)
- One of the most common Pipe Fittings Manufacturing Process for manufacturing Elbows Or Pipe Bends from the pipe is mandrel method which is kind of hot forming methods.
- In this method, the pipe is cut in pieces and push with the help of hydraulic ram. It is pushed over a die called “mandrel” which allows the pipe to expand and bend simultaneously.
- This method can be used to manufacture a wide range of the diameter of elbows or pipe bends
-
- ELBOWS Or Pipe Bends Mandrel method
Extrusion Method
In cold Extrusion method, a pipe with the same diameter as finished product is pushed through a die and formed into its desired shape. Usually applied to stainless steel small to medium sizes elbows or pipe bends.
Extrusion Method
UO Method
UO method is used to manufacture medium size of the elbow, tee, and reducers. The plate is cut out into a specially designed shape, it is formed first into a U-shape using a die and then into an O-shape or tubular form using another die, that is why this method is known as UO method. Once the fittings formed in tumbler shaped it is welded from inside and outside of the closing seam. A cut plate is 1st from in U shape and then in O shape.
UO Method
Hot Forming Method
In a Hot Forming Die Bending method, a Pipe is heated to forming temperature & formed in the die with the specific shape, this process may be repeated as needed to obtain the required shape, size and wall thickness. Usually applied to thick-wall items that cannot be bent on a mandrel die.