# E7018 welding electrode

E7018 classification, hydrogen and moisture designations, product operating limits and controlled storage for low-hydrogen SMAW welding.

Reviewed: 2026-11-01

Tags: consumables, welding, smaw, electrodes, low-hydrogen

Hobart **7018 XLM**, **E7018-1 H4R**, permits **DCEP or AC**. Its instructions distinguish **250–300°F holding** from controlled reconditioning at **600°F for one hour** after extended exposure. Use the applicable job code and the exact product's handling history before deciding whether an exposed electrode can be used. [Hobart Brothers, *7018 XLM datasheet*, p. 1](https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/datasheets/7018XLM.pdf)

E7018 is a low-hydrogen, iron-powder SMAW class. Preserve the full product designation and verify the applicable handling requirements. [Hobart Brothers, *7018 XLM product details*](https://www.hobartbrothers.com/product/product-details/hobart-7018-xlm/)

## Read classification separately from approval

The “70” denotes a **70,000 psi minimum tensile-strength class** under classification testing, while “1” denotes all-position usability. Current type and covering are encoded by the final digit; E7018 is associated with low-hydrogen iron-powder covering. These are classification characteristics, not a guaranteed strength for a complete fabricated joint. Miller's selection guidance requires considering base-metal composition, tensile strength, joint geometry, position and service conditions together. [Miller, *Factors for selecting the right stick electrode*](https://www.millerwelds.com/en-US/resources/knowledge-hub/stick-welding/factors-for-selecting-the-right-stick-electrode); [Hobart Brothers, *7018 XLM*](https://www.hobartbrothers.com/product/product-details/hobart-7018-xlm/)

Additional suffixes carry separate information:

| Marking | What to check |
| --- | --- |
| E7018 versus E7018-1 | Retain the exact classification and its impact-test requirements; do not silently drop “-1” |
| H4 | Maximum diffusible-hydrogen designation of 4 mL per 100 g deposited weld metal under the applicable test |
| R | Additional moisture-resistance requirements; not unlimited resistance to shop humidity or water |

Hobart explains that R-designated products resist moisture pickup, while codes can still limit exposure and reconditioning. Low-hydrogen classification controls one hydrogen source; it does not eliminate hydrogen introduced elsewhere in production. [Hobart Brothers, *Gaining benefits with low-hydrogen filler metals*](https://www.hobartbrothers.com/resources/technical-articles/gaining-benefits-with-low-hydrogen-filler-metals/); [Miller, *How to control hydrogen in welding*](https://www.millerwelds.com/en-us/resources/knowledge-hub/field-welding/pipe/the-hydrogen-problem)

A product approval is another record. Hobart's product page lists AWS classification, certifications and ABS/CWB approvals separately. Verify the specified product, diameter, package and applicable approval when purchasing for controlled work. A brand's general structural-welding description is not an approval for an unspecified pressure vessel, bridge or service temperature. [Hobart Brothers, *7018 XLM product details*](https://www.hobartbrothers.com/product/product-details/hobart-7018-xlm/)

## Properties belong to stated test conditions

Hobart's **7018 XLM datasheet revision `250915`**, replacing `250911`, reports typical as-welded tensile strength of **77,000 psi** and average Charpy V-notch impact energy of **117 J at −46°C**. These typical test results do not establish joint design stress, production toughness or minimum service temperature. [Hobart Brothers, *7018 XLM datasheet*, p. 1](https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/datasheets/7018XLM.pdf)

Its linked certificate offers a useful evidence boundary. The actual document was **tested October 8, 2026 and generated October 15, 2026**, covering **5/32 and 3/16 in** test sizes. It identifies the record as **EN 10204 type 2.2 non-specific inspection** and states particular polarity, preheat and interpass test conditions. This is not a certificate uniquely tracing the user's electrode lot or production weld. Obtain the required lot documentation rather than treating a publicly linked typical certificate as a substitute. [Hobart Brothers, *7018 XLM certificate of conformance*](https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/certifications/HOBART_7018XLMTypCert.pdf)

## Polarity, diameter and procedure

Use the purchased product's operating table with the welding procedure specification (WPS). The 7018 XLM sheet gives these **DCEP or AC** ranges:

| Diameter | Published current range |
| --- | --- |
| 3/32 in (2.4 mm) | 70–110 A |
| 1/8 in (3.2 mm) | 90–160 A |
| 5/32 in (4.0 mm) | 110–230 A |
| 3/16 in (4.8 mm) | 190–300 A |

Vertical-down welding is not recommended. Separate deposition-rate figures use optimum DCEP parameters, rather than every position or AC setup. [Hobart Brothers, *7018 XLM datasheet*, pp. 1–2](https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/datasheets/7018XLM.pdf)

Confirm that the power source supports the specified current type, required output and duty cycle. Match electrode diameter and technique to joint access, fit-up, position and the WPS. The all-position classification does not authorize a particular travel direction, bead width or pass sequence. Likewise, changing to a higher-strength electrode solely because it appears “stronger” does not establish compatibility with the base material or service. [Miller, *Electrode selection*](https://www.millerwelds.com/en-US/resources/knowledge-hub/stick-welding/factors-for-selecting-the-right-stick-electrode)

## Low hydrogen requires process control

Hydrogen-assisted cracking depends on hydrogen, a susceptible microstructure and stress. Miller notes that it can appear hours or days after welding. Low-hydrogen filler helps, but preheat/interpass control, material handling and other procedure decisions still matter. Do not infer that E7018 removes the need for specified preheat, delayed inspection or joint preparation. Those requirements belong to the particular material, restraint, thickness and governing procedure. [Miller, *How to control hydrogen in welding*](https://www.millerwelds.com/en-us/resources/knowledge-hub/field-welding/pipe/the-hydrogen-problem)

Moisture is not confined to the electrode: base-metal contamination and handling can introduce hydrogen too. Hobart's pipeline guidance treats filler selection, pre/post-weld heating, interpass temperatures and storage as complementary controls. E7018 is therefore not an automatic replacement for cellulosic electrodes in an existing pipe-root procedure; a process or filler change requires checking the actual procedure and qualification boundaries. [Hobart Brothers, *Sources and remedies of hydrogen-assisted cracking*](https://www.hobartbrothers.com/resources/technical-articles/the-hydrogen-problem-understanding-the-sources-and-remedies-of-hydrogen-assisted-cracking-in-transmission-pipeline-applications/)

## Holding, exposure and reconditioning

Keep unopened packaging intact and protect it from water and damage. After opening, use the manufacturer's controlled storage arrangements and the job's exposure limits. Hobart warns that leaving packages open or storing them improperly on site compromises low-hydrogen consumables. Its product page distinguishes ordinary cartons from hermetically sealed cans; a carton is not equivalent to a sealed metal package merely because both contain the same trade product. [Hobart Brothers, *Keeping filler metals in top shape on the job site*](https://www.hobartbrothers.com/resources/technical-articles/keeping-filler-metals-in-top-shape-on-the-job-site/); [Hobart Brothers, *7018 XLM packaging*](https://www.hobartbrothers.com/product/product-details/hobart-7018-xlm/)

Holding limits moisture pickup. Reconditioning attempts to remove absorbed moisture. Follow current 7018 XLM instructions and the WPS for the controlled heating ramp and exposure limits. Evaluate wet or damaged stock separately. [Hobart Brothers, *7018 XLM datasheet*](https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/datasheets/7018XLM.pdf)

Neither H4R nor successful arc striking proves that an exposed electrode still meets required hydrogen performance. Hobart notes that job codes may restrict time out of packaging and the number of reconditioning cycles. Keep product identity and exposure history available so the required disposition can be made; do not invent an exposure allowance from the R suffix. [Hobart Brothers, *Low-hydrogen filler-metal storage considerations*](https://www.hobartbrothers.com/resources/technical-articles/gaining-benefits-with-low-hydrogen-filler-metals/)

## Handling and welding exposure

The linked North American **Hobart 7018XLM SDS**, product code **S4220**, is **version 1.0, revised January 8, 2026**. Its as-shipped classification does not remove hazards from welding: it warns about fumes, electric shock and arc radiation. It calls for ventilation/local exhaust and suitable hand, eye, head and body protection. Fume composition also depends on base metal, coatings and process conditions, rather than matching the solid electrode's ingredient percentages. Use the actual product SDS with the equipment and workplace controls, including precautions for hot electrode stubs and dust during cleanup. [Hobart Brothers, *7018XLM SDS*](https://www.hobartbrothers.com/wp-content/uploads/hobart-catalog/msds/Hobart_7018XLM_S4220_V1_NA_EN.pdf)

## Related reference

[Shielded metal arc welding](../../processes/welding-methods/shielded-metal-arc-welding.md)