Properties of Common SMAW Electrodes

SMAW, (Shielded Manual Arc Welding) or more commonly known simply as “stick” welding is still the most widely used welding method. And carbon steel is still the most widely used steel. And for the previous reasons, it is also the most common electrode specification referenced in welding procedures. The electrodes in this group are the fabrication “work horses” throughout the welding world. There is very little useful online information about the welding electrodes used for carbon steel welding. This welding article should give you most of the electrode performance information that you need to either write your own WPS, PQR, or to review a welding procedure for this electrode group. It can also help with selection of the correct electrode based upon available job specifications, welding equipment, position of welding, and base metal.  

                                                         Classification of Electrodes

Notes to Above Table:

A.      Welding Position Abbreviations as Follows:

F=Flat

H=Horizontal

H-fillets=Horizontal Fillets

V-down=Vertical with Downward Progression

V=Vertical and OH=Overhead. For electrodes 3/16 in. (4.8 mm) and under, except 5/32 in. (4.0 mm) and under for classifications

 E7014, E7015, E7016, E7018, and E7018M.

B.       The term “ac” means alternating current. The term “dcep” means direct current electrode positive (dc, reverse polarity). The term

“dcen” means direct current electrode negative (dc, straight polarity).

C.      Electrodes of the E6022 class are used for single pass welds only.

Typical Amperage Ranges

Note: n/a=Not Applicable. The electrode is not manufactured in that diameter.

Welding Electrode Numbering System

The welding numbering system consists of mandatory designators and optional supplemental designators. The letter “E” is a mandatory designator. The four or five following numbers are also mandatory. The letter “M” following these is also a mandatory requirement for military electrodes. Any additional numbers or letters are optional and designate specific additional testing that the electrode manufacturer has complied with. The easiest way to explain this seemingly complicated process is with a couple of electrode examples:

1.       E7018M

2.      E7018-1HZR

1.       E7018M

“E” is simply the designator for electrode.

“70” designates the minimum tensile strength in ksi (thousands of pounds per square inch) as proven by testing according to code specification by the manufacturer. Electrodes made for other specifications include 80, 90, 110, 120 and other ksi tensile strengths.

“1” designates that this electrode is all position. A “2” designation in the same location would be for flat and horizontal only.

“8” designates the composition of the flux coating which in this case is low hydrogen iron powder.

“M” designates that this electrode meets most military requirements for greater toughness and lower moisture content.

2.      E7018-1HZR

The “E7018” portion will have the same breakdown as above. The rest are optional supplemental designators.

“-1” designates that the electrodes “E7016” and “E7018” meet the requirements for improved toughness. For “E7024” electrodes, it also means improved ductility in addition to the improved toughness.

“HZ” designates that the electrode meets the requirements of the diffusible hydrogen supplemental test of the weld metal.

“R” designates that the electrode meets the requirements of the absorbed moisture supplemental test. This is a mandatory test for “M” or military applicable electrodes.

Uses and Performance Characteristics of SFA 5.1 Welding Electrodes

E6010 Electrodes

E6010 electrodes penetrate deeply and the arc is similar to spray arc welding. The slag is thin and may not completely cover the weld bead. The welds usually have an uneven rippled look to them. Fillet welds will be relatively flat.  These electrodes are commonly used for welding carbon, galvanized, and some low alloy steels. These welding electrodes are designed for use with DCEP (electrode positive) current.

E6011 Electrodes

E6011 electrodes are for use primarily with ac current, although they will run with DCEP, but at a reduced weld penetration. They are designed to duplicate the usability and welding ability characteristics of E6010.

E6012 Electrodes

E6012 electrodes have a low penetrating arc and thick heavy slag.  Small size fillet welds can be difficult to make and may have incomplete root penetration with this electrode.  In the vertical and overhead positions, E6012 will produce a larger size fillet weld with a convex weld face compared to E6010 or E6011. The weld ripples are rough looking but will smooth out somewhat as the bead size increases. These electrodes are good for bridging wide gaps due to poor fit-up. For vertical and overhead welding, electrode size selection should be one size smaller than for E6010 or E6011.

E6013 Electrodes

E6013 electrodes are similar in welding characteristics to E6012. They were designed primarily for use with light sheet metal and produce a much smoother arc transfer.  The slag removal is easier due to the different coating (high titania potassium). These characteristics allow

this electrode to be manufactured in smaller than standard electrode diameter sizes. Fillet welds have a flat rather than convex appearance.

Groove welds exhibit a concave weld face and the weld metal remains freer of slag and oxide inclusions. This allows sound welds with the smaller diameter electrode sizes that often meet Grade 1 radiographic requirements.

E6019 Electrodes

E6019 electrodes also meet the Grade 1 radiographic requirements. They provide a deeper arc penetration than E6013 and E6020 and are suitable for multipass welds on steel up to one inch thick.  The slag is easy to remove. Weaving in the vertical up position will frequently cause undercutting (edge melt) and should be kept to a minimum.

E6020 Electrodes

E6020 electrodes run similar to E6010 with a medium to deeply penetrating welding arc depending upon welding current.  This electrode produces a smooth and flat or slightly concave weld face with easily removable slag. E6020 electrodes are best used on thicker base material.

E6022 Electrodes

E6022 electrodes are designed for single pass, high current, high-speed welding of flat groove welds or horizontal lap joints. The weld face is more convex in appearance and the weld face is usually less uniform due to the higher welding speeds.

E6027 Electrodes

E6027 electrodes have similar arc characteristics to E6010 and E6020 with a medium penetrating spray type arc. The heavy electrode covering (high iron oxide, iron powder) produces a thick, but easy to remove slag. Weld faces are flat to slightly concave with a smooth and even ripple. These electrodes are suited for multi-pass welding on thicker base metal.

E7014 Electrodes

E7014 electrodes have similar welding characteristics to E6012 and can bridge wide gaps also. The addition of iron powder allows higher amperage and deposition rates and its use as an all position welding electrode. These electrodes can be used for carbon or low allow steel.

Fillet weld faces are usually flat to slightly convex. Welding slag is easy to remove.

E7027 Electrodes

E7027 electrodes have the same weld ability and performance characteristics as E6027, but are designed for applications requiring higher yield and tensile strengths.

Low Hydrogen Welding Electrodes

E7015 Electrodes

E7015 electrodes, like all low hydrogen electrodes, require a short arc length (usually no more than 1/8” or 3.2 mm) to prevent porosity in the weld bead. These electrodes are commonly used for making small welds on thick base metal and for welding high sulphur and enameling steels. On normal carbon steel, the slag is thick and easy to remove. On high sulfur steels, the slag is tightly adhering and more difficult to remove and produces an irregular looking weld bead compared to welding on normal steels.

E7016 Electrodes

E7016 electrodes have similar welding characteristics as E7015 except that they were designed with the ability to be used with ac current also. E7016-1 has manganese content at the high end of the acceptable range and is intended for welds requiring a lower transition temperature. (The transition temperature is basically the rise in temperature of the welded base metal that will change the mechanical properties of the steel from ductile to brittle. Certain steels have a narrow transition range and require post weld heat treatment to return the welded steel back to its original mechanical properties to prevent fracture cracking).

E7018 Electrodes

E7018 electrodes are used to join regular carbon, high-strength, high carbon, or low alloy steels. Welding characteristics are the same as E7015 or E7016. The welds produced have a slightly convex face and a smooth finely rippled surface. They have medium penetration, low spatter, and a smooth quiet arc. E7018-1 1 has manganese content at the high end of the acceptable range and is intended for welds requiring a lower transition temperature as with E7016-1.

E7018M Electrodes

E7018M electrodes have the same welding characteristics as E7018 electrodes. Additional code specific testing requirements are required for a welding electrode to have the “M” designation such