What is electrode run-out length?

What is electrode run-out length?

Electrode run-out length is a term used in Shielded Metal Arc Welding (SMAW) or also called the Stick Welding process.

Electrode run-out length refers to the distance of weld made by a single welding electrode during the welding process. It is determined by the length of the electrode, which is typically around 350-450mm, and the welding speed.

In simple words, electrode run-out length is the length of weld deposited by each individual electrode.

What are the effects of electrode run-out length on Welding?

During welding, the electrode run-out length affects the welding in terms of weld deposition, weld penetration, mechanical properties as well as weld appearance.

In short, electrode run-out length effects in welding are:

  1. Weld Penetration: Electrode run-out length can affect the depth of penetration of the weld. A shorter electrode run-out length can produce a deeper weld, while a longer electrode run-out length can result in shallower penetration. The ideal electrode run-out length for a particular welding application depends on the material being welded, the thickness of the material, and other factors.
  2. Welding Speed: The electrode run-out length is also related to welding speed. A longer electrode run-out length can allow for higher welding speeds, but this can also lead to reduced quality if the welding process is not properly controlled. Conversely, a shorter electrode run-out length may require slower welding speeds to ensure proper weld quality.
  3. Weld Bead Appearance: Electrode run-out length can affect the appearance of the weld bead. A longer electrode run-out length can result in a narrower, more focused weld bead, while a shorter electrode run-out length can produce a wider, more spread-out weld bead.
  4. Welding mechanical properties: A smaller Electrode run-out length results in low travel speed and hence high welding heat input while a longer run-out is equal to higher travel speed and thus better mechanical properties of the weld.
See also  Welding Machine Duty Cycle Calculator

Related reading: Effects of heat input in welding.

How to increase or decrease electrode run-out length?

Electrode run-out length can be increased by using a higher travel speed or using stringer weld beads.

To reduce the electrode run-out length, you can use weld weaving or low travel speed.


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