fbpx

GB 5310 25MnG high pressure seamless boiler tubes

GB 5310 25MnG is a low-alloy steel that is commonly used for making high-pressure seamless boiler tubes.

Please send your inquiry by   sales@sunnysteel.com

Description

GB 5310 25MnG tubes are similar to 20MnG and other low-alloy steels used for boiler tubes, but with slightly different composition and mechanical properties.

25MnG high-pressure seamless boiler tubes have applications in power plant boilers, where they can be found in superheaters, reheaters, steam pipes, and other high-pressure components. The working pressure for the use of these tubes is typically above 9.8 MPa, and the working temperature is between 450℃ and 650℃.

Some of the key features of 25MnG high-pressure seamless boiler tubes include good strength and toughness, excellent dimensional accuracy, and high-temperature performance. They also have a low thermal expansion coefficient, which reduces thermal stress during operation, and good corrosion resistance to ensure their durability.

The production and use of 25MnG high-pressure seamless boiler tubes must comply with strict standards to guarantee safety and reliability in service. Different end types are available, such as plain end, beveled end, or threaded ends, and the tubes can come in various lengths, outer diameters, and wall thicknesses.

In summary, GB 5310 25MnG high-pressure seamless boiler tubes are another type of low-alloy steel that offers excellent mechanical properties and high-temperature strength. They are widely used in power plant boilers and their quality and performance are critical factors for ensuring reliable and safe operation.

Manufacturing methods

(1)Steel smelting method
GB 5310 25MnG steel will be smelted by electric furnace plus furnace refining, oxygen converter plus furnace refining or electroslag remelting method.

(2)Manufacturing methods and requirements for tube blanks
The 25MnG tube blank can be produced by continuous casting, die casting or hot rolling (forging).

(3)Manufacturing method of steel tube
GB 5310 25MnG Steel tubes shall be manufactured by hot rolling (extrusion, expansion) or cold drawing (rolling).

GB 5310 20MnG is another low-alloy steel that is commonly used for making high-pressure seamless boiler tubes.

Chemical composition of GB 5310 25MnG high pressure seamless boiler tubes

Steel Grade C Si Mn S P
25MnG 0.22-0.27 0.17-0.37 0.70-1.00 0.015 0.025

Mechanical properties of GB 5310 25MnG high pressure seamless boiler tubes

Grade Tensile strength Yield point(Mpa) Elongation(%) Impact(J)
(Mpa) not less than not less than not less than
25MnG 485-640 275 20/18 40/27

Application of GB 5310 25MnG high pressure seamless boiler tubes:

GB 5310 25MnG is a low-alloy steel that is commonly used to manufacture high-pressure seamless boiler tubes. These tubes have applications in power plant boilers, where they are used for various components including:

  1. Superheaters: 25MnG high-pressure seamless boiler tubes are used to construct superheaters in power plant boilers. Superheaters increase the temperature of steam to improve the efficiency of the power plant.
  2. Reheaters: Similar to 20MnG and other low-alloy steels, 25MnG high-pressure seamless boiler tubes are also used to make reheaters in power plant boilers. Reheaters reheat the steam after it has passed through the turbine’s first stage.
  3. Steam Pipes: 25MnG high-pressure seamless boiler tubes are used to transport high-pressure steam between the different stages of the power generation process in power plant boilers.
  4. Other high-pressure components: In addition to superheaters and reheaters, 25MnG high-pressure seamless boiler tubes are used to make other high-pressure components such as headers, steam walls, and economizers, among others.

The working pressure for the use of 25MnG high-pressure seamless boiler tubes is typically above 9.8 MPa, and the working temperature is between 450℃ and 650℃. The quality and performance of these tubes are critical for ensuring safety and reliability in power plant operations.

25MnG high-pressure seamless boiler tubes are essential components in power plant boilers, where they play a crucial role in facilitating the transfer of high-pressure steam throughout the system. These tubes offer excellent mechanical properties, durability, and resistance to corrosion and oxidation at high temperatures, making them suitable for use in harsh industrial environments.

The main features of GB 5310 25MnG high pressure seamless boiler tubes:

GB 5310 25MnG is a low-alloy steel that is commonly used for producing high-pressure seamless boiler tubes. Some of the main features of 25MnG include:

  1. High strength: 25MnG has good tensile strength and yield strength, which makes it suitable for use in high-pressure applications.
  2. Good toughness: Similar to other low-alloy steels used for boiler tubes, 25MnG has excellent toughness, which reduces the risk of brittle fracture during operation.
  3. Corrosion resistance: The composition of 25MnG includes elements like manganese, which provide good resistance to corrosion and oxidation at high temperatures.
  4. Low thermal expansion coefficient: 25MnG has a low thermal expansion coefficient, which reduces the risk of thermal stress during operation.
  5. Good dimensional accuracy: 25MnG high-pressure seamless boiler tubes have precise dimensions and tolerances, which ensures that they fit perfectly and function correctly in their intended applications.
  6. High-temperature performance: 25MnG can withstand high temperatures of up to 650℃, making it suitable for use in high-temperature environments.
  7. Durability: When manufactured according to strict standards, 25MnG high-pressure seamless boiler tubes offer reliable and safe performance in high-pressure, high-temperature applications.

In summary, 25MnG high-pressure seamless boiler tubes are known for their high strength, good toughness, corrosion resistance, low thermal expansion coefficient, high-temperature performance, and durability. These features make them suitable for use as critical components in power plant boilers, where safety and reliability are paramount.

Standard

The production of our seamless pipes is tightly regulated and all of the pipes we stock have been fully tested to international standards to ensure we only supply the highest quality products.

ASTM / ASME

American Society for Testing and Materials(ASTM), American Society of Mechanical Engineers (ASME)
Product nameExecutive standardDimension (mm)Steel code/ Steel grade
Black and Hot-dipped Zinc-coated Steel Pipes SeamlessASTM A530.3-1200 x 1.0-150GR.A, GR.B, GR.C
Seamless Carbon Steel for High Temperature ServiceASTM A10610.3-1200 x 1.0-150GR.B, GR.C
Seamless Cold-drawn Low-Carbon Steel Heat-Exchanger and Condenser TubesASTM A17910.3-426 x 1.0-36Low Carbon Steel
Seamless Carbon Steel Boiler Tubes for High PressureASTM A19210.3-426 x 1.0-36Low Carbon Steel
Seamless Cold-drawn Intermediate Alloy Steel Heat-exchanger and Condenser TubesASTM A19910.3-426 x 1.0-36T5, T22
Seamless Medium-carbon Steel Boiler and Superheater TubesASTM A21010.3-426 x 1.0-36A1, C
Seamless Ferritic and Austenitic Alloy Steel Boiler, Superheater and Heat-exchanger TubesASTM A21310.3-426 x 1.0-36T5, T5b, T9 , T11, T22 ,T91
Seamless Carbon and Alloy Steel for Mechanical TubingASTM A3331/4"-42" x SCH20-XXSGrade1 Gr. 3,Gr..6, Gr.8 , Gr. 9
Seamless Cold-drawn Carbon Steel Feedwater Heater TubesASTM A55610.3-426 x 1.0-36A2, B2
Round and shaped steel cold formed welded and seamless carbon steel structural pipe.ASTM A500OD :10.3-820 x 0.8- 75Grade A, B, C, D
Carbon and alloy steel mechanical tubing, either hot-finished or cold-finishedASTM A51910.3-426 x 1.0-361020, 1025, 4130, 4140
For seamless ferritic alloy-steel pipe for high-temperature serviceASTM A3351/4"-42" x SCH20-XXSA/SA 335 P1, P2, P11, P12, P15, P22, P91, P92, P122

Process

Cold drawn seamless steel tube deformed process

Cold Drawn Seamless Mechanical Tubing (CDS) is a cold drawn 1018/1026 steel tube which offers uniform tolerances, enhanced machinability and increased strength and tolerances compared to hot-rolled products. Cold drawn seamless steel tubes process Cold drawn steel tube is with hot-rolled steel coil as raw material, and tandem cold rolling pickled to remove oxide scale, its finished rolling hard roll, rolling hard volumes due to the continuous cold deformation caused by cold hardening strength, hardness increased indicators declined tough plastic, stamping performance will deteriorate, which can only be used for simple deformation of the parts. Rolling hard roll can be used as the raw material of the hot-dip galvanizing plant, hot dip galvanizing line set annealing line. Rolling hard roll weight is generally 6 to 13.5 tons, the coil diameter of 610mm.


Hot rolled seamless steel pipe deformed process

Hot-rolled seamless steel pipe production base deformation process can be summarized as three stages: perforation, extension and finishing. Hot rolled seamless steel pipe deformed process The main purpose of the perforation process is to become a solid round billet piercing hollow shell. Capillary in the specifications, accuracy and surface quality can not meet the requirements of the finished product, further improvements are needed to deform the metal through. The main purpose of the stretching machine is further reduced sectional view (main compression wall) for a larger axial extension, so that the capillary improved dimensional accuracy, surface quality and organizational performance. After stretching machine rolled steel pipe shortage collectively need further molding mill in order to achieve the requirements of the finished pipe. Rolled steel due to pass in the method widely used in the production of seamless steel tubes. So far, due to the method pass rolling steel can be divided into two categories: core pension without rolling rolling (hollow body rolling), and with the mandrel. Sizing machines, reducing mill and stretch reducing mill belonging to the hole without mandrel type continuous rolling mills are generally coffin. Its main purpose is to reduce the diameter of the deformation process or sizing get finished steel, the wall thickness of process control, can make thinning, thickening or nearly unchanged. All the traditional hole-type rolling machine with mandrel belong to extend machine. The main purpose is to reduce the deformation process perforated capillary wall thickness and outer diameter roll passes in the deformation zone and the mandrel posed, for a larger axial extension. At the same time a certain improvement in the organization, performance, accuracy, surface quality.


Cut to LengthASTM A210 seamless medium carbon steel boiler and superheater tubes

Before cutting pipe and tubing No matter the material, measure the diameter of the pipe or tube to be cut to ensure that you use the right-size tube cutter for the job. When determining how to make a straight cut, use a tape measure and a pencil or other writing instrument to mark on the surface where you want to cut. If possible, mark around the circumference of a pipe, especially when cutting with a handsaw. Ensure that a cut is as straight as possible by securing the pipe with a vise, clamp, miter box or even duct tape to keep the length from shifting out of place while cutting. After cutting pipe and tubing

  • Unless a cut is perfectly clean, you should expect to remove burrs from around the edge, especially after sawing.
  • Use a deburring tool to clean the edge after tube cutting.
  • You may opt to use a metal file on the cut of a metal pipe.

Inspection

Size inspection

Geometrical inspection of steel pipes The outer diameter, wall thickness, bending and length of the steel pipe can be inspected on the inspection table with an outer caliper, a micrometer and a bending ruler, and a length tape measure.

Tolerances of pipes you should notice

Take seamless steel pipe as an example, there are some tolerances that affect quality. Noting this, and you will get a better pipe.

Weight tolerance
For pipe NPS 12 (DN300, 323.8mm) and under, the weight shall vary within -3.5% / +10%.

For pipe over NPS 12 (DN300, 323.8mm), the weight shall vary within -5% / +10%.

Pipe of NPS 4 (DN100, 114.3mm) and smaller may be weighed in convenient lots; pipe in sizes larger than NPS 4 shall be weighed separately.

Quantity tolerance
Normally mills take -10% to +10% tolerance, but TPMCSTEEL keeps ±3% variation.

Length tolerance
For Seamless pipe& tube, if definite cut lengths are ordered, the length shall vary within -0mm / +6mm.

Dimension tolerances of seamless steel pipe

Pipe typesPipe Szie(mm)Tolerances
Hot rolledOD<50±0.50mm
≥50±1%
WT<4±12.5%
≥4-20+15%, -12.5%
>20±12.5%
Cold drawnOD6-10±0.20mm
10-30±0.40mm
30-50±0.45
>50±1%
WT<1±0.15mm
>1-3+ 15%, – 10%
>3+ 12.5%, – 10%
StandardHot finished seamless tubeCold flnished seamless tube
Out diameter
(mm)
ToleranceOut diameter
(mm)
Tolerance
EN10216-1≤100 +/-0.75%
(min.+/-0.5mm)
All +/-0.5%
EN10216-2(min. +/-0.30mm)
DIN17175>100 +/-0.90%
GB/T 3087≤460 +/-0.75%
(min.+/-0.5mm)
 10-30  +/-0.40mm
>30-50 +/-0.45mm
>50 +/-1.0%
GB/T 5310
GB/T 9948
GB/T 6479
<57 +/-0.40mm≤30 +/-0.20mm 
 57-325  +/-0.75%>30-50  +/-0.30mm 
>325-460 +1%,-2mm>50 +/-0.8% 
ASME SA-179M
ASME SA-192M
ASME SA-209M
ASME SA-210M
ASME SA-213M
JIS G 3461
JIS G 3461
≤101.6 +0.4, -0.8mm<25.4 +/-0.10mm
>25.4-38.1 +/-0.15mm
>38.1-50.8 +/-0.20mm 
101.6-190.5 +0.4, -1.2mm>50.8-63.5 +/-0.25mm
>63.5-76.2 +/-0.30mm 
>76.2 +/-0.38mm
ASME SA106
ASME SA335
≤48.3 +/-0.40mm ≤48.3 +/-0.40mm
 48.3-114.3 +/-0.79mm 
114.4-219.1 +1.59, -0.79mm 
219.2-323.9 +2.38, -0.79mm>48.3 +/-0.79mm 
>324 +/-1.0%

Tolerances on wall thickness

The wall thickness at any point shall be within the below tolerance table.
StandardHot finished seamless tubeCold flnished seamless tube
DIN17175Out diameter
OD(mm)
Wall thickness
T(mm)
ToleranceOut diameter
(mm)
Wall Thickness
T(mm)
Tolerance
≤130S≤2Sn +15%, -10%   --All +/-10%
(min. +/-0.2mm)
2Sn +12.5%, -10% 
S>4Sn +-/9%
>130S≤0.05da +17.5%, -12.5% 
0.05da +/-12.5% 
S>0.11da +/-10% 
EN 10216-1
EN 10216-2
 ≤219.1  -   +/-12.5%
(min.+/-0.4mm) 
 -- T/D≤0.025 +/-20% 
0.025 +/-15% 
0.05 +/-12.5% 
0.1 +/-10% 
GB/T 3087 -- ≤20 +15%,-12.5%
(min.+0.45, -0.35mm)
 --  1.0-3.0  +15%, -10% 
>20 +/-12.5%  -- >3 +12.5%, -10% 
GB/T 5310
GB/T 9948
GB/T 6479
 -- <4.0 +15%,-10%
(min.+0.48, -0.32mm)
 --  2-3  +12%,-10% 
 4-20  +12.5%,-10% >3 +/-10% 
>20 +/-10%
ASME SA-179M
ASME SA-192M
ASME SA-209M
ASME SA-210M
ASME SA-231M
JIS G 3461
JIS G 3462
 --  2.41-3.8  +35%, -0% ≤38.1 --  +20%,-0% 
 3.8-4.6  +33%,-0% >38.1 -- 22%,-0% 
>4.6 +28%,-0%  --  --  -- 
ASME SA-106
ASME SA-335
 -- All +/12.5% All +/-10% 

Note:

  1. The size in the table above is for the hot-rolled tubes.
  2. The size of the green area is the regular specification, we can accept orders directly, but the yellow area shall be subject to a technical evaluation.
  3. The Out side diameter (O.D) and wall thickness (W.T.) of the tube should be complied.

PMI test

Positive material identification (PMI) testing is the examination of a material, usually a metallic alloy, to confirm the material is consistent with the user’s request.

Delivery

Steel pipe delivery status(condition)

Steel pipe delivery status(condition): cold / hard (BK), cold / soft (BKW), after cold stress relief annealing (BKS), annealing (GBK), normalized (NBK).

Condition on delivery of steel pipe

TermSymbolExplanation
Cold-finished/hard (cold-finished as-drawn)BKNo heat treatment after the last cold-forming process. The tubes therefore have only low deformability.
Cold-finished/soft (lightly cold-worked)BKWAfter the last heat treatment there is a light finishing pass (cold drawing) With proper subsequent processing, the tube can be cold-formed (e.g. bent, expanded) within certain limits.
AnnealedGBKAfter the final cold-forming process the tubes are annealed in a controlled atmosphere or under vacuum.
NormalizedNBKThe tubes are annealed above the upper transformation point in a controlled atmosphere or under vacuum.
The general cold strip mills, volume should go through continuous annealing (CAPL unit) to eliminate cold hardening and rolling stress, or batch annealing reach the mechanical properties of the corresponding standard specifies. Cold rolled steel surface quality, appearance, dimensional accuracy better than hot-rolled plate, and right-rolled thin product thickness is about 0.18mm, so the majority of users favor.

Cold rolled steel coil substrate products deep processing of high value-added products. Such as electro-galvanized, hot dip galvanized, electro-galvanized fingerprint resistant, painted steel roll damping composite steel, PVC laminating steel plates, etc., so that the excellent quality of these products has a beautiful, high resistance to corrosion, has been widely used.

Cold rolled steel coil finishing after annealing, cut the head, tail, trimming, flattening, smooth, heavy volume, or longitudinal clipboard. Cold-rolled products are widely used in automobile manufacturing, household electrical appliances, instruments, switches, buildings, office furniture and other industries. Steel plate strapping package weight of 3 to 5 tons. Flat sub-volume typically 3 to 10 tons / volume. Coil diameter 6m.


Packing

There are probably hundreds of different methods for packing a pipe, and most of them have merit, but there are two principles that are vital for any method to work prevent rusting and Sea transportation security.

  • Plastic caps plugged at the two sides of pipe ends
  • Should be avoided by the steel strapping and transport damage
  • Bundled signs should be uniform and consistent
  • The same bundle(batch) of steel pipe should be came from the same furnace.
  • The steel pipe has the same furnace number, the same steel grade, the same specifications.

Our packing can meet any needs of the customers.

Inquiry

Need to inquire about our products? Fill out the form below and our staff will be in touch!

Contact Form Demo

FAQ

Q: How long is your delivery time? A: The delivery time of customized products is generally 25 35 days, and non customized products are generally shipped within 24 hours after payment. Q: Do you provide samples? Is it free? A: If the value of the sample is low, we will provide it for free, but the freight needs to be paid by the customer. But for some high value samples, we need to charge a fee. Q: What are your payment terms? A: T/T 30% as the deposit,The balance payment is paid in full before shipment Q: What is the packaging and transportation form? A: Non steaming wooden box and iron frame packaging. Special packaging is available according to customer needs. The transportation is mainly by sea. Q: What is your minimum order quantity? A: There is no minimum order quantity requirement. Customized products are tailor made according to the drawings provided by the customer.