E7018 Welding Rod: Amperage Chart, Settings & When to Use
E7018 Amperage by Diameter
| Diameter | Amperage Range |
|---|---|
| 3/32" (2.4 mm) | 65 - 100A |
| 1/8" (3.2 mm) | 110 - 160A |
| 5/32" (4 mm) | 130 - 200A |
| 3/16" (4.8 mm) | 200 - 280A |
| 7/32" (5.6 mm) | 260 - 340A |
| 1/4" (6.4 mm) | 300 - 400A |
E7018 is the most widely used structural welding rod. It has a low-hydrogen coating that prevents cracking and produces smooth, strong welds you can trust on load-bearing joints. If a welding code or blueprint calls out a specific rod, it is usually this one. The "70" means 70,000 psi tensile strength, and the "18" tells you it is a low-hydrogen iron powder rod that runs on DCEP or AC.
What This Means in Practice
If a structural drawing calls out a welding rod, it is almost always E7018. The low-hydrogen coating means your welds will not crack on thick steel or in cold weather. The trade-off is storage: you need a rod oven. If you do not have one, your welds will have porosity on anything that matters. For non-critical shop work without an oven, consider E7014 instead.
E7018 Suitability Scores
How well this electrode matches common applications. Not a quality rating. all AWS-certified electrodes meet their specification.
When to Use E7018
Structural steel, buildings, bridges, beams.
Pressure vessels and boilers.
Pipe fill and cap passes after a 6010 root.
Any joint that needs to pass inspection or X-ray.
Welding in cold conditions where cracking is a concern.
Thick plate where hydrogen cracking is a risk.
E7018 Limitations
Must be kept dry, store opened rods in a rod oven at 250-300F or they absorb moisture and your welds will have porosity.
Cannot run vertical-down.
Needs clean, dry steel to work properly, not the rod for rusty field repairs (use E6010 or E6011 for that).
Slag can be stubborn in tight corners.
E7018 Storage Requirements
Store in rod oven at 250-300F (120-150C) after opening. If exposed to atmosphere for more than 4 hours, recondition at 700-800F (370-425C) for 1 hour. Hermetically sealed (H4R) varieties resist moisture for up to 9 hours at 80F/80% RH.
E7018 Technical Specifications
| Property | Value |
|---|---|
| AWS Classification | E7018 |
| Process | Stick Welding (SMAW) |
| Polarity | DCEP, AC |
| Positions | flat, horizontal, vertical up, overhead |
| Penetration | medium |
| Coating Type | low-hydrogen iron powder |
| Tensile Strength | 70,000 psi |
| Yield Strength | 58,000 psi |
| Elongation | 22% |
| Impact Toughness | 20 ft-lbs at -20°F |
| Base Metals | carbon steel, low-alloy steel, high-strength low-alloy steel |
| AWS Specification | A5.1 |
Common Questions About E7018
Can I run E7018 on an AC welder?
Yes, but it depends on the machine. Standard E7018 needs at least 70-80V open circuit voltage to hold an arc on AC. Most industrial AC/DC machines can handle it. Smaller buzz box welders (like the Lincoln AC-225) can struggle with standard E7018, the arc will sputter and be hard to restart. If you have a smaller AC-only machine, buy E7018AC rods. They have a modified flux that arc-starts easier on low-OCV machines. For code or structural work, always run E7018 on DCEP. If you only have a buzz box and need an easy-running all-position rod, E6011 is a better fit for AC. See also: E6013 vs E7018 comparison.
Do I need a rod oven for E7018?
For code work, yes. E7018 is a low-hydrogen rod and its coating absorbs moisture from the air. Wet rods cause porosity and hydrogen cracking. After you open a sealed container, rods should go into an oven at 250-300F. If they have been out in the air more than 4 hours, recondition them at 700-800F for one hour before use. For non-critical farm and shop repairs, many welders get by with keeping opened rods in a sealed plastic container, but the welds will not meet code.
What happens if E7018 rods get wet?
Moisture in the flux coating releases hydrogen into the weld pool. This causes two problems: porosity (gas pockets trapped in the weld) and hydrogen-induced cracking, which can happen hours or days after welding. On thick or high-strength steel, hydrogen cracking can cause a weld to fail with no warning. If your rods have been exposed to humidity or rain, recondition them in an oven at 700-800F for one hour. If the coating is visibly damaged or flaking, discard them.
What amperage for 1/8 inch E7018?
Start at 110-160A for 1/8 inch (3.2 mm) E7018. Use the lower end (110-125A) for vertical-up and overhead. Use the higher end (140-160A) for flat and horizontal fillets. If the rod is sticking or the bead is piling up, increase amperage 5-10A. If you are burning through or getting excessive spatter, reduce. These are starting points, adjust based on fit-up, material thickness, and your machine.
Is E7018 good for beginners?
E7018 is one of the easier rods to run once you have basic arc control. It has a smooth, quiet arc, low spatter, and the slag peels off cleanly. However, it is not the best rod to learn on because it is sensitive to moisture and requires proper storage. Most instructors start students on E6013 for basic technique, then move to E7018 for structural practice. If you are learning in a school or shop with a rod oven, E7018 is fine to start with. E6013 specifications, the easier rod most instructors recommend for beginners. See also: E6013 vs E7018 comparison.
Where to Buy E7018
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External Resources
Manufacturer data sheets and standards for E7018.
Data sourced from AWS A5.1/A5.1M. Amperage ranges are approximate starting points. adjust based on position, fit-up, and material thickness. Always follow manufacturer recommendations and applicable codes.