AK-657Q Low-Hydrogen Sodium Electrode for High-Toughness Bridge Steel Welding.
An all-position, ultra-low hydrogen electrode with high toughness for critical low-alloy steel structures, designed for demanding applications like Q500qE bridge components.
Product Overview
AK-657Q is a low-hydrogen sodium type covered electrode for manual metal arc welding, formulated for all-position welding with DC reverse polarity. It delivers high toughness and low hydrogen content to minimize the risk of hydrogen-induced cracking in critical structures.
The electrode meets EN ISO 18275-A E 55 5 Mn1 NiMo B 4 2, AWS A5.5 E9015-D1, and GB/T 5118-1995 E6015-G classifications. It is specifically intended for welding important low-alloy steels such as Q500qE used in bridge structures.
Application: lt is used for bridge welding structures such as important low-alloy steel Q500qE.
Key Benefits
Ultra-Low Hydrogen Content
The sodium-based coating minimizes hydrogen in the weld metal, reducing the risk of cold cracking in high-strength, low-alloy steels during and after welding.
High Toughness at Low Temperature.
The deposited metal achieves impact values of at least 47 J at minus 40 degrees C, ensuring reliable performance in cold environments.
All-Position Welding Capability
AK-657Q can be used in flat, horizontal, vertical, and overhead positions, enabling consistent weld quality across complex joint geometries without changing consumables.
Controlled Chemical Composition
The electrode’s chemistry includes 0.8-1.7% Ni and 0.1-0.4% Mo, which enhances strength and toughness while maintaining good weldability in high-strength steels.
Where It Is Used
- Welding of bridge structures made from low-alloy steel Q500qE.
- Critical structural components requiring high toughness and low hydrogen content.
- All-position welding in fabrication and field erection of heavy steel structures.
Who It Is For
- Welding consumable distributors supplying high-performance electrodes for structural steel.
- Bridge and heavy steel structure fabricators working with high-strength low-alloy steels.
- Contractors requiring certified, consistent filler metal for critical welds in demanding environments.
Problems It Solves
- Risk of hydrogen-induced cracking in high-strength steels due to high hydrogen content in the weld metal.
- Inconsistent mechanical properties when using electrodes not matched to the base metal’s strength and toughness requirements.
- Need for multiple electrode types to cover different welding positions on the same structure.
Specifications
Published by the factory for AK-657Q. Values not shown are not published on the datasheet and are marked as such rather than estimated.
| Standard | Designation |
|---|---|
| Classification 1 | EN ISO 18275-A E 55 5 Mn1 NiMo B 4 2 |
| Classification 2 | AWS A5.5 E9015-D1, GB/T 5118-1995 E6015-G |
| Element | Content |
|---|---|
| C | ≤0.10 |
| Si | ≤0.6 |
| Mn | 1.0-2.0 |
| S | ≤0.015 |
| P | ≤0.020 |
| Ni | 0.8-1.7 |
| Mo | 0.1-0.4 |
| Property | Value |
|---|---|
| Tensile strength (MPa) | ≥630 |
| Yield Stress (MPa) | ≥530 |
| Elongation (%) | ≥17J |
| Impact values (J) | ≥47J/-40℃ |
| Diameter | Current range |
|---|---|
| 2.5mm | F/H-70-110A V/OH-50-80A |
| 3.2mm | F/H-90-130A V/OH-80-110A |
| 4.0mm | F/H-140-180A V/OH-130-170A |
Technical Features
- Low-hydrogen sodium type coating with DC reverse polarity requirement.
- Deposited metal tensile strength at least 630 MPa, yield stress at least 530 MPa.
- Elongation at least 17 percent and impact energy at least 47 J at minus 40 degrees C.
- Chemical composition: C ≤0.10%, Si ≤0.6%, Mn 1.0-2.0%, S ≤0.015%, P ≤0.020%, Ni 0.8-1.7%, Mo 0.1-0.4%
- Available in 2.5 mm, 3.2 mm, and 4.0 mm diameters with specified current ranges for each position.
Use Guide
- Select diameter by joint thickness and position: 2.5 mm for thin sections, 3.2 mm for medium, 4.0 mm for thicker sections.
- Use DC reverse polarity (DCEN) for stable arc and proper slag formation.
- Set current within the recommended range: 2.5 mm – 70-110 A flat/horizontal, 50-80 A vertical/overhead; 3.2 mm – 90-130 A flat/horizontal, 80-110 A vertical/overhead; 4.0 mm – 140-180 A flat/horizontal, 130-170 A vertical/overhead.
- Keep electrodes dry in sealed packaging; re-dry if exposed to moisture before use.
- Remove slag completely between passes to prevent inclusions and ensure sound welds.
How It Compares
AK-657Q and E9015-D1 both belong to the low-hydrogen sodium type and are used for high-strength low-alloy steels. AK-657Q is specifically formulated for bridge structures like Q500qE, with a controlled Ni and Mo content to enhance toughness. Other electrodes in the E9015 family may have different alloying elements or impact values. For applications requiring lower hydrogen and higher toughness at low temperatures, AK-657Q is a suitable choice over general-purpose electrodes.
Related Grades
Other welding electrodes in the same family.
AK-657Q Questions
What classifications does AK-657Q meet?
What are the mechanical properties of the deposited metal?
What are the recommended welding parameters?
Can I get technical data and packing details before ordering?
What packing is AK-657Q supplied in?
Can we test AK-657Q before placing a production order?
Request a Quotation for AK-657Q
Send the diameter, the quantity and the destination port. Our technical team replies with packing, pricing and the data you need to qualify the grade.