E7016 Welding Rod

In Stick Welding (SMAW) electrodes, the E7018 gets all the glory as the “structural king,” and the E6010 is revered as the “pipe welder’s best friend.” But sitting quietly between them is the E7016—a rod that is often misunderstood, frequently underutilized, but absolutely critical for specific high-stakes applications.

If you are welding pressure vessels, heavy-wall pipes, or crack-sensitive steels where a root pass is required without a backing strip, the E7016 is likely your secret weapon. It offers the low-hydrogen safety of an E7018 but without the heavy iron powder, giving you a completely different level of puddle control.

The E7016 is a Low Hydrogen welding rod similar to the E7015 electrode but can also be used with AC Polarity. E7016 welding rod has a tensile strength of 70 Ksi.

• Classification: E7016 (EN ISO 2560-A: E38 4B 42 H5)
• Specification: AWS A 5.1
• Welding Polarity: AC and DCEP (Electrode Positive)

Form: Low Hydrogen Potassium Covered Electrode for Stick Welding (Shielded Metal Arc Welding).

E7016 Electrode Chemical Composition and Mechanical Properties

The Chemical Composition and Mechanical Properties of E7016 welding rod as per AWS A5.1 specification are given in the below table. The tensile strength of E7016 electrode is 70 Ksi, Yield strength is 58 Ksi and toughness is 20 ft·lbf at –20°F (27 J at –30°C).

Decoding the Code: What is E7016?

Before we strike an arc, we must decode the American Welding Society (AWS) classification A5.1.

• E: Indicates this is an Electrode.
• 70: Indicates a minimum tensile strength of 70,000 psi (approx. 480 MPa) in the as-welded condition. This makes it a high-strength rod suitable for structural steel.
• 1: Indicates All-Position capability (Flat, Horizontal, Vertical, Overhead).
• 6: This is the chemical fingerprint. It indicates a Low Hydrogen Potassium coating.
  • Low Hydrogen: The flux is engineered to contain minimal moisture, preventing Hydrogen Induced Cracking (Cold Cracking).
  • Potassium: This element is added to the flux to act as an arc stabilizer, specifically allowing this rod to run on AC (Alternating Current) as well as DC+ (DCEP).

The “Double-Coated” Variant

You may sometimes see E7016 referred to as a “Double-Coated” electrode (e.g., E7016-1 or E7016 SPE). These are premium versions often used for “One-Sided Welding” on pipe roots. The inner coating ensures arc stability, while the outer coating creates a crater that focuses the arc force, simulating the deep penetration of a cellulosic rod like E6010 but with low-hydrogen chemistry.

The Behavior: How Does It Run?

If you are used to running E7018, the first time you pick up an E7016, it will feel “thin.”

No Iron Powder

The biggest physical difference is the lack of iron powder in the flux.

• E7018 has ~25-40% iron powder in the coating. This melts into the weld pool, increasing deposition rates (filling the joint faster) and making the puddle more fluid/sluggish.
• E7016 has little to no iron powder.

What this means for you:

1. Faster Freezing: The puddle solidifies much faster than E7018. This makes E7016 exceptional for Vertical-Up and Overhead welding because the metal doesn’t try to drip on you.
2. Open Root Capability: Because the puddle isn’t “heavy” or overly fluid, you can bridge an open root gap (like on a pipe joint) much easier than with E7018.
3. Thinner Slag: The slag layer is thinner and glassier. It doesn’t peel off as automatically as E7018; it might require a bit more chipping, especially in deep grooves.
4. The Ripple: E7016 produces a distinct, fine ripple pattern that is aesthetically pleasing but different from the smooth “wash” of a 7018.

The Showdown: E7016 vs. other welding electrodes

To truly understand where E7016 fits, we have to compare it to the other rods in your quiver.

🥊 Round 1: E7016 vs. E7018 (The Sibling Rivalry)

This is the most common confusion. Both are Low Hydrogen. Both are 70,000 psi. Why choose one over the other?

Feature	E7016	E7018
Coating	Low Hydrogen Potassium (No Iron Powder)	Low Hydrogen Potassium (With Iron Powder)
Deposition Rate	Lower (Slower to fill)	Higher (Fills joints fast)
Puddle Fluidity	Fast Freezing (Stiff)	Fluid (Wet)
Root Pass	Excellent (Bridges gaps well)	Poor (Too fluid, blows through)
Restarts	Difficult (Porosity risk at start)	Easier
Primary Use	Root passes, Pipe welding	Fill & Cap passes, Structural steel

The Verdict: Use E7016 for the root pass (if 6010 isn’t allowed) to bridge the gap. Then, switch to E7018 for the fill and cap passes to save time.

🥊 Round 2: E7016 vs. E6010 (The Root Pass War)

E6010 (Cellulosic) is the standard for pipe roots. But on high-strength steels (like X70 or X80 pipe), the hydrogen in E6010 can cause cracking.

Feature	E7016	E6010
Hydrogen Level	Very Low ($<8\text{ml}/100\text{g}$)	High (Cellulose = Hydrogen)
Penetration	Medium	Deep / Digging
Slag	Medium/Heavy	Very Light
Cracking Risk	Low (Safe for high carbon steel)	High (Risk of HIC cracking)
Technique	Drag or slight weave	Whip and Pause

The Verdict: If you are welding mild steel pipe, E6010 is faster. But if you are welding thick-wall pressure vessels, high-yield piping, or crack-sensitive alloys, you MUST switch to E7016 for the root to prevent hydrogen cracking. This is standard in the nuclear and petrochemical industries.

🥊 Round 3: E7016 vs. E6013 (The Professional vs. The Hobbyist)

E6013 (Rutile) is a user-friendly rod, but it lacks the toughness for critical code work.

• Penetration: E7016 penetrates deeper than the shallow E6013.
• Slag Control: E6013 slag is notorious for getting trapped (inclusions) in multipass welds. E7016 slag floats to the surface better, making it superior for multi-pass X-ray quality welds.
• Ductility: E7016 welds can stretch and flex without breaking (high impact toughness). E6013 welds are more brittle.

The Verdict: Never use E6013 on a pressure vessel or structural beam. E7016 is the code-compliant alternative.

🥊 Round 4: E7016 vs. E7015 (The Ancestor)

E7015 was the original low-hydrogen rod. It has a Sodium-based coating.

• The Difference: Sodium (E7015) only works on DC+ (Direct Current). Potassium (E7016) works on AC and DC+.
• Arc Physics: The potassium in E7016 ionizes the arc gap, keeping the arc ignited even when the AC sine wave crosses zero volts. E7015 would snuff out on AC.
• Usage: E7015 is rarely seen today because E7016 does everything E7015 does, plus it runs on AC welders (transformers).

Key Applications: When to grab the E7016?

You shouldn’t use E7016 for everything—it’s slower than E7018. However, it is the only choice for:

1. Single-Sided Pipe Welding (SSAW): When you need to weld a pipe from the outside only, and you need a radiographic-quality root bead without a backing ring. The fast-freeze characteristic allows you to put in a “keyhole” root similar to 6010, but with low hydrogen properties.
2. Poor Fit-Up: If you have a wide gap to bridge on a structural joint, E7018 will just spill through. E7016 will freeze across the gap, acting like a bridge.
3. High-Sulphur Steels: Steels with high sulphur content are prone to “Hot Cracking.” E7016 (and 7018) contains manganese which combines with sulphur to form Manganese Sulphide, preventing cracks.
4. Field Repairs on AC Machines: If you are in the field with an old “Buzz Box” (AC Transformer welder) and need to do a structural repair, you can’t use E7018 efficiently (unless it’s E7018-AC). E7016 is natively designed for AC.

Operational Guide: Running the Rod

Amperage Settings

E7016 generally runs slightly cooler than E7018 because it lacks the iron powder carrier.

• 2.5mm (3/32″): 60 – 90 Amps
• 3.2mm (1/8″): 90 – 130 Amps
• 4.0mm (5/32″): 130 – 180 Amps

Arc Length (Critical!)

This is where most beginners fail. E7016 requires a Short Arc.

• Long Arc: If you pull a long arc, the shielding gas protection dissipates, and you will get porosity immediately.
• Short Arc: Keep the rod almost touching the puddle. You should feel the coating “dragging” slightly on the plate.

Re-Start Technique

Low hydrogen rods are notorious for “Starting Porosity.” When you strike the arc, the nitrogen in the air rushes in before the shielding gas is established.

• Technique: Strike the arc about 1-2 inches ahead of the weld, drag it back to the crater (pre-heating the path), and then weld over the strike mark. This burns out any porosity formed at the ignition point.

Storage and Handling: The Moisture Enemy

Like all Low-Hydrogen electrodes, the E7016 is a sponge. The flux coating is hygroscopic—it absorbs moisture from the air.

• The Danger: If water ($H_2O$) gets into the coating, the intense heat of the arc breaks it down into Hydrogen and Oxygen. The Hydrogen diffuses into the weld metal and causes Underbead Cracking (Hydrogen Embrittlement).
• The Rules:
  1. Hermetic Seal: Keep cans sealed until ready to use.
  2. Oven Storage: Once opened, store in a holding oven at 100 Deg C to $150Deg C (212 Deg F-300 DegF).
  3. Re-Baking: If exposed to air for more than 4 hours (depending on humidity), they must be re-baked at 300 Deg C to 350Deg C (570^ DegF-660 Deg F) for 2 hours before use on code work.

Note: Do not re-bake electrodes more than three times, as the binder in the flux will become brittle and flake off.

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Summary Comparison Table

Parameter	E6010	E6013	E7016	E7018
Classification	High Cellulose	Rutile	Low Hydrogen	Low Hydrogen Iron Powder
Penetration	Deep	Shallow	Medium	Medium
Current	DC+ Only	AC, DC+/-	AC, DC+	AC, DC+
Deposition	Low	Medium	Medium	High
Slag Removal	Excellent	Good	Good	Excellent
Toughness	Good	Poor	Excellent	Excellent
Best For	Roots, Rusty Steel	Sheet Metal	Roots, Positional	Filling, Cap, Heavy Plate

E7016 Welding Rod

E7016 welding rod is a low hydrogen electrode having similar characteristic of E7015 however E7016 can be used with AC and DCEP Polarity.

E7016 rod gives a crack resistant weld compared toE7018 rod on thick material welding and useful for welding on heavy weld seams or restrained welding joints to avert cracking.

7016 Welding Rod Polarity

E7016 Welding Rod Polarity is AC and DCEP (Electrode positive, or Reverse polarity).

E67016 Welding Rod uses

This low hydrogen Welding rod is used for welding applications for:

• Welding of low carbon to medium carbon steel.
• Welding barrier weld layer before hard facing.
• Welding of ASTM A515, 516, 570, 572, 607 and 668 grades.
• High cracking resistance for welding thick materials.
• E7016 gives a ductile weld that is beneficial for API pipelines jobs where hardness control is required.

Storage and baking of E7016 Welding Electrode

Being a low hydrogen electrode, E7016 requiresbaking/ drying before use. The recommended drying or baking temperature for E7016 rod as per AWS A5.1, Table 1.3 is 500- 800°F (260- 425°C) for 1- 2 hours.

Baked or dried electrode shall be kept in portable holding oven at a temperature of 50- 250°F (30- 140°C) during use. Unused electrodes shall be returned back to stationary holding ovens.

E7016 Welding Rod amperage

E7016 welding electrode amperage depend on the electrode diameter. 3/32” rod is good with 75- 110 ampere, 1/8” with 100- 150 ampere and 5/32” with 150 to 190 ampere current.

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