A common question that is asked when manufacturers are trying to determine costs associated with welding is: **How many pounds of wire can I deposit per hour? Or, how many pounds of wire can I deposit at a specific amperage or wire feed speed? ** There are charts to help you determine this, but unless you want 5 or 6 pages of size 6 font you are better off using a simple formula.

Before we get into this calculation is very important to make a distinction between deposition rate and melt-off rate. A lot of people in our industry use these two terms interchangeably and that is not correct. Melt-off rate is how much wire is being consumed and does not take into account the efficiency of the electrode. Deposition rate is how much wire is actually converted into weld metal. Solid wire efficiencies can range from 88 – 98%, so you can have the exact same melt-off rate but considerably different deposition rates if you are welding at the same wire feed speed but with a different mode of metal transfer.

So now to the formula:

**Deposition Rate = 13.1 (D²) (WFS)(EE)**

**D** = electrode diameter

**WFS** = wire feed speed (in/min)

**EE** = electrode efficiency

**13.1** is a constant used for steel and it is based on steels density. This same constant can be used for stainless steel wires as it is only 1/1000 difference. Aluminum on the other hand would have to be a constant of about a third that of steel, or 4.32.

Electrode efficiencies for solid wires can vary depending on the mode of metal transfer. We are not going to get into the specifics of how to achieve each at this time. Below are typical efficiencies for each of the modes.

Short-circuit Transfer: 90-93%

Surface Tension Transfer: 98% (STT is a trademark and of the Lincoln Electric Company)

Globular Transfer: 88 – 90%

Axial Spray Transfer: 98%

Pulsed Spray Transfer: 98% is typical, but can be lower depending on the parameters and power source

**Example:*** A customer wants to know the deposition rate of an .052 ER70S-6 wire. They are running 90/10 shielding gas at 320 in/min and 30 volts. We are in spray transfer mode at these settings.*

**Deposition Rate** = 13.1(0.052)² (320) (0.98) = **11.1 pounds per hour**

How did you translate the deposition rate to pounds per hour when your wire feed speed is in inches per minute?

Hello Kelby. The formula provided in the above article does the calculation for you. But, if you want to do it the long way all you need to know if the diameter and the wire feed speed. If you take the diameter of the wire you can calculate the cross sectional area (A=πr2). If you know the speed in inches per minute you know the the length of wire by unit of time. So you are able to determine the length of wire fed and from here the volume (Area * Length). This give you a a number in cubic inches per minute being fed. You then take the density of steel (0.283 lbs/cubic inch). When you multiply those two units you get the result in pounds/minute which can then be translated to pounds per hour. Hope this helps.

Would my travel speed be the same if I am trying to use a weave with a dwell in the horizontal position?

If you have dwell time your travel speed would decrease; however, your bead would be bigger than just doing a stringer.

Hi, I can use this formula in the metric system? I also want to know which literature is this formula. Congratulations on the site! I can get out of difficult situations with the knowledge that I have been getting.

Hello Matthew,

This formula cannot be used in the metric since the 13.1 constant is specific to the imperial system. The above formula comes from Lincoln Electric’s GMAW Guide as shown at the bottom of the article. This can also be found on the Procedure Handbook of Arc Welding (you can find a link to this on our Resources tab). The Procedure Handbook does include Metric System formulas. We will search for the metric formula and provide if found.

Thank you very much!

I need to know how calculate the deposition rate has been placed in the vertical position during the SMAW welding

Please refer to the post on “Deposition Rates for Stick Electrodes” by following the link below

http://weldinganswers.com/deposition-rates-for-stick-electrodes/

If you know the current you are using simply used the formulas provided for the type of electrode you are using.

Pls provide book for my reference.

Which book do you need? If you want the free Guide on Writing a Welding Procedure Specification simply enter your name and email address on the side bar and then confirm your free subscription when you receive the welcome email.

Does this formula apply to stainless steel GMAW wire as well?

Yes, you can use it for stainless. The density of stainless steel is almost identical to that of carbon steel. If you were running aluminum then this formula would no longer be applicable.