E7018 Welding Electrode Meaning
E7018 welding rod is a mild steel Stick Welding Rod having low hydrogen covering and can be used for all position welding.
E7018 rod can be used with AC and DCEP (Reverse polarity)- Electrode positive. The electrode coating of E7018 is mixed with Iron-powder to increase the amount of weld deposit compared to E7015, E6013 rods, etc.
Related Reading: E7018 Electrode Chemical, Mechanical Properties.
E7018 Electrode Specification & Classification
The Electrode specification for E7018 is AWS A5.1. E7018 is the classification number for this rod.
E7018 Welding Rod Amperage & Current
As a thump rule, welding amperage for E7018 is 70 ampere to 200 ampere. 70- 100 amperage is used for 3/32 inch diameter rod, 90- 150 for 1/8 inch diameter rod, and 150- 200 amperage for 5/32 inch diameter.
Welding with AC Polarity needs high welding amperage compared to DCEP when using E7018 welding rod. Refer below table for recommended Welding Amperage Chart for E7018 Welding Rod:
|Welding Rod Diameter||DCEP Amperage||AC Amperage|
|3/32-inch (2.5 mm)||70 -100||70- 125|
|1/8-inch (3.2 mm)||90- 150||100- 150|
|5/32-inch (4 mm)||125- 200||150- 200|
|3/16-inch (5 mm)||175- 300||200- 310|
E7018 Welding Rod Polarity
E7018 Welding rod is used with AC Polarity and Reverse polarity ( Electrode positive).
E7018 H4R, H8R Meaning
E7018H4R means that there will be less than 4 ml molecular hydrogen present in a 100 gram of welding deposit made with this electrode (<4ml/100g).
Similarly, E7018H8R means that there will be less than 8 ml molecular hydrogen present in a 100 gram of welding deposit made with this electrode (<8ml/100g).
E7018 Welding Rod AC or DC?
E7018 Welding rod has Potassium in its covering. Potassium has very good electron transfer capability due to large atom size.
Hence, E7018 can be used with AC polarity as well as DC polarity. with DC, mainly Reverse polarity (DCEP-Electrode positive) is used.
E7018 Welding Rod Sizes
According to the AWS A5.1 Stick Welding rod specification for carbon steel, E7018 Welding rod is available in:
- 3/32 inch (2.4 mm)
- 1/8-inch (3.2 mm)
- 3/16 inch (4.8 mm)
- 7/32 inch (5.6 mm)
- 1/4 inch (6.4 mm)
The most commonly used E7018 welding rod sizes are 3/32, 1/8 and 3/16 inches.
E7018 Welding Rod Oven Temperature for Baking & Holding
E7018 is a low Hydrogen rod and require baking at a oven temperature of 500°F to 800°F (260°C- 525°C) for 1 to 2 hours period.
The holding oven temperature for E7018 rod is 50°F to 250°F (30°C- 140°C). These temperature recommendation are according to the AWS A5.1 Specification.