In recent years, with the increasing demand for high-strength steel (such as 490MPa grade) welding in shipbuilding, bridge engineering, pressure vessels and other fields, E71T-1C flux-cored welding wire has become an important driving force for technological innovation in the industry due to its excellent performance and wide applicability. The following analyzes its innovation potential from three aspects: technical characteristics, application scenarios and industry impact.
I. Technical features: high efficiency and multi-scenario adaptation
As a titanium calcium type (Rutile) flux-cored wire, E71T-1C adopts 100% CO₂ or mixed gas protection, supports all-position welding (including vertical upward, vertical downward, overhead welding, etc.), and has the following advantages:
- High deposition rate and low spatter: Compared with traditional welding materials, its deposition efficiency is significantly improved, the amount of spatter is reduced, and the weld surface is smooth, which is suitable for automated welding scenarios.
- Excellent low-temperature toughness: The weld metal can still maintain high impact toughness at -20℃ (such as a typical value of 145J), meeting the needs of extreme environments.
- Low hydrogen design: By optimizing the flux core formula and sealed packaging, the diffusible hydrogen content is reduced, the risk of cold cracks is reduced, and welding safety is improved.
III. Application scenarios: from traditional manufacturing to high-difficulty engineering
- Shipbuilding and marine engineering: Evidence shows that E71T-1C was used by Kobe Steel in Japan as early as the 1980s to replace manual welding rods, promoting the automation transformation of the shipbuilding industry. Its vertical downward welding capability greatly improves the efficiency of thick plate welding, especially for ultra-large container ships.
- Pressure vessels and bridges: The welding wire has stable performance in 490MPa-grade high-strength steel welding and has been successfully applied to landmark projects such as the West-East Gas Pipeline and the Shanghai Lupu Bridge, verifying its reliability and process adaptability.
- Support for complex working conditions: Through low smoke emission and anti-porosity design, E71T-1C can cope with harsh working conditions such as rust and oil pollution, reducing pretreatment costs.
iII. Industry impact: technology upgrade and standard guidance
- Promoting process innovation: The multi-position welding capability and high deposition rate of E71T-1C simplify the traditional welding process that relies on multiple processes, and improve production efficiency by more than 30%.
- International certification coverage: The welding wire has been certified by nine classification societies such as ABS, DNV, and LR, and complies with global standards such as AWS, ISO, and GB/T, becoming the mainstream choice for multinational projects.
- Industry chain collaborative innovation: Chinese manufacturers such as Shanghai Welding Group (SWEC) have achieved breakthroughs in high-end fields such as aerospace and nuclear power through independent research and development, demonstrating the strength of domestic technology.
Typical Tensile Properties
| Condition | Yield Strength | Tensile Strength | Elongation |
|---|---|---|---|
| As Welded (AWS C1 gas) | 491 MPa | 563 MPa | 30% |
Deposition Parameters
| Diameter | Current Range | Voltage Range | Feed Speed | Deposition Rate |
|---|---|---|---|---|
| 1.2 mm | 140–330 A | 22–34 V | 5.1–15.2 m/min | 1.7–5.3 kg/h |
| 1.6 mm | 170–460 A | 24–36 V | 3.8–12.7 m/min | 2.5–8.3 kg/h |
Charpy Impact Test
| Condition | Test Temperature | Impact Value |
|---|---|---|
| As Welded (AWS C1 gas) | 0 °C | 90 J |
| As Welded (AWS C1 gas) | -20 °C | 58 J |
Notes:
Retained technical standards (e.g., AWS A5.20) and units (MPa, J, m/min, kg/h) to ensure clarity.
Adjusted URL formatting for correctness.
Translated terminology aligns with industry standards (e.g., "alambre tubular rutílico" → "rutile-type tubular wire").
Outlook: Continue to expand the application boundaries of high-strength steel
- Although E71T-1C is currently mainly used for 490MPa grade steel, the higher strength E81T1 series welding wire (such as 590MPa grade) has begun to emerge. In the future, by optimizing the alloy composition and gas protection scheme, E71T-1C is expected to further break through the strength limit and become the cornerstone of continuous innovation in high-strength steel welding technology.
- In summary, E71T-1C flux-cored welding wire, with its high efficiency, reliability and strong adaptability, not only solves the pain points of traditional welding, but also opens up a new development path for high-strength steel welding technology through standardization and large-scale application. Its innovative value has been widely recognized by the global industry.
What are the specific technical innovations of E71T-1C flux-cored wire in high-strength steel welding?
The specific technical innovations of E71T-1C flux-cored wire in high-strength steel welding are mainly reflected in the following aspects:
Excellent welding performance:
E71T-1C welding wire has low spatter, stable arc and good slag release performance, which makes the welding process smoother, the weld is beautiful and easy to clean.
This welding wire is suitable for all-position welding, including flat welding, vertical welding and overhead welding, which can meet the needs of different welding positions.
High welding efficiency:
E71T-1C welding wire adopts a unique manufacturing process, and the surface is covered with a uniform copper plating layer and lubricant coating, which ensures excellent wire feeding and conductivity, thereby improving welding efficiency.
The high coating efficiency and good all-position welding technical performance of the welding wire make it perform well in high-strength steel structures such as ships, pressure vessels, mechanical equipment and bridges.
Excellent mechanical properties:
The deposited metal of E71T-1C welding wire has been toughened with trace elements, with good low-temperature toughness, good crack resistance and stable intrinsic quality.
Its mechanical properties include yield strength of 583MPa, tensile strength of 621MPa, elongation of 30% and Charpy V-notch impact toughness (-20℃: 100J; -70℃: 30J), which ensure the high strength and durability of the weld.
Wide range of applications:
E71T-1C welding wire is suitable for welding low-carbon steel and 490N/mm² (500MPa grade) high-strength steel, and is widely used in shipbuilding, machinery manufacturing, pressure vessels, boilers, petroleum machinery, chemical machinery, lifting machinery and other structures.
In addition, this welding wire is also suitable for butt welding and fillet welding of various structural parts of low-carbon steel and 490N/mm² high-strength steel such as ships and marine structures.
Special shielding gas requirements:
E71T-1C welding wire is usually used in conjunction with carbon dioxide gas. It is recommended to use carbon dioxide shielding gas with a purity of more than 99.8% to ensure welding quality.
In some cases, Ar/CO2 mixed gas can also be used for protection to further improve welding performance.
Application of low-hydrogen welding materials:
In some special welding processes, such as welding of dissimilar steels A572 and A514, E71T-1C welding wire is selected as low-hydrogen welding material to meet the requirements of low-hydrogen welding materials and ensure the low-temperature toughness and crack resistance of the weld.
The technical innovation of E71T-1C flux-cored welding wire in high-strength steel welding is mainly reflected in its excellent welding performance, high welding efficiency, stable mechanical properties, wide application range and requirements for special protective gas.
What are the advantages and disadvantages of E71T-1C flux-cored wire compared to other high-strength steel welding technologies (such as the E81T1 series)?
Compared with other high-strength steel welding technologies (such as the E81T1 series), the E71T-1C flux-cored wire has the following advantages and disadvantages:
Advantages
1. All-position welding capability:
E71T-1C flux-cored wire is suitable for welding in all positions, including vertical, flat and horizontal welding, which makes it more flexible and convenient during construction.
2.Low spatter and good arc stability:
E71T-1C welding wire has extremely low spatter and stable arc, which helps improve welding efficiency and weld quality.
3. Good weld formation and mechanical properties:
E71T-1C welding wire can produce beautiful weld formation and has good mechanical properties such as high tensile strength and elongation.
4. Suitable for a variety of materials:
E71T-1C welding wire is not only suitable for low carbon steel and low alloy steel, but also can be used for welding of 500MPa grade high-strength steel, such as ships, pressure vessels, mechanical equipment and bridges.
5. No shielding gas required:
E71T-1C welding wire adopts a self-shielding design and does not require additional shielding gas, which reduces welding costs and improves the flexibility of the welding process.
6. Excellent crack resistance:
E71T-1C welding wire has good crack resistance, especially under low temperature conditions, which makes it perform well in demanding welding applications.
Disadvantages
1. High welding process requirements: Although E71T-1C welding wire is suitable for a variety of welding positions, its welding process requirements are high, and the operator needs to have certain skills and experience.
2. High requirements for the cleanliness of the base material: Flux-cored welding wire has high requirements for the cleanliness of the base material. If there are impurities or oxides on the surface of the base material, the quality of the weld may be affected.
3. The welding speed may be limited: Although E71T-1C welding wire has good all-position welding capabilities, in some cases, its welding speed may not be as fast as solid welding wire, especially in applications that require fast welding.
4. Cost issues: The cost of flux-cored welding wire is generally higher than that of solid welding wire, which may affect its application in some low-cost projects.
5. Welding environment requirements: Flux-cored welding wire may be affected to a certain extent in a windy environment. Although its self-protecting design can resist wind to a certain extent, it still needs to be paid attention to under extreme conditions.
Summary
E71T-1C flux-cored wire has significant advantages in all-position welding, low spatter, good arc stability, crack resistance, etc., and is suitable for welding a variety of high-strength steels. However, its main shortcomings are its high requirements for base material cleanliness, strict welding process requirements, and relatively high cost.
What are the application cases of E71T-1C flux-cored welding wire in the field of automated welding?
E71T-1C flux-cored wire has a wide range of applications in the field of automated welding, mainly in the following aspects:
- Shipbuilding: E71T-1C flux-cored wire is widely used in shipbuilding due to its excellent welding performance and all-position welding capabilities. For example, AWS A5.20 E71T-1C welding wire is suitable for low carbon steel and 490N/mm² thick steel, and can be welded in all positions to ensure the quality and strength of the weld. In addition, Kobelco Group's FAMILIARC YJZ-7333 E71T-1C welding wire is also particularly suitable for ship welding, with good weld formation and low spatter characteristics.
- Building structure: In the construction industry, E71T-1C flux-cored wire also performs well. For example, TOKO AWS A5.20 E71T-1C welding wire is suitable for various welding applications in the construction industry, especially in full penetration welding (FCAW), which can provide a stable arc and good weld quality. In addition, the intelligent welding wire factory produced by Qingming Yuanda Welding Materials Co., Ltd. also emphasized the application of E71T-1C welding wire in building structures, especially the efficient welding performance in automatic welding and semi-automatic welding.
- Mechanical manufacturing:E71T-1C flux-cored welding wire is also widely used in the field of mechanical manufacturing. For example, AWS A5.20 E71T-1C welding wire is suitable for low-carbon steel and 490N/mm² thick steel in mechanical manufacturing, and can be welded in all positions to ensure the quality and strength of the weld. In addition, the JQ.CE71T-1C welding wire produced by Tianjin Jinqiao Chemical is also particularly suitable for welding low-carbon steel and 490Mpa grade high-strength steel in mechanical manufacturing.
- Pressure vessels and boilers: In pressure vessel and boiler manufacturing, E71T-1C flux-cored welding wire is widely used in these high-demand welding scenarios due to its excellent welding performance and low spatter characteristics. For example, the E71T-1C welding wire produced by Qingming Yuanda Welding Materials Co., Ltd. is suitable for welding of pressure vessels, boilers and other equipment, with good weld quality and production efficiency.
- Nuclear power engineering: E71T-1C flux-cored welding wire is also used in nuclear power engineering. For example, the JQ.CE71T-1C welding wire produced by Tianjin Jinqiao Chemical is particularly suitable for welding low-carbon steel and 490Mpa-grade high-strength steel in nuclear power engineering, with good welding process performance and weld quality.
- Other applications: In addition, E71T-1C flux-cored welding wire is also widely used in other fields such as bridges, storage tanks, and steel structures. For example, the FAMILIARC YJZ-7333 E71T-1C welding wire of Kobe Steel Group is suitable for welding bridges and building structures, with good weld formation and low spatter characteristics.
In summary, the application of E71T-1C flux-cored welding wire in the field of automated welding is very extensive, covering many fields such as shipbuilding, building structures, machinery manufacturing, pressure vessels and boilers, and nuclear power engineering.
