definition: electrode recovery (MMA-SMAW)

[kingnero]

I need to perform some tests for determining the chemical match between a certain filler metal (stick welding electrodes) and a base material.
This standard prescribes, as a very first test, a "single bead test", which is essentially a single bead on the base metal, in order to check visually and with dye penetrant.

The standard mentions: The welded bead shall be maximum electrode recovery using the manufacturer's parameters.

English is not my native language, so could someone please elaborate what they mean with this?
Is it the maximum length of a welded bead, done with a single electrode?
Has it got to do with stringer beads or weaving? The current with which we will be welding? Anything else?

I do understand recovery, but not in this context/phrase.
Thanks in advance...

 

[Duwe6]

English is my native language, and I've been a Certified Welding Inspector since 1984, have designed and qualified Welding Procedures i.a.w. ASME and API for decades. . . .

And I don't understand this either. Probably time to send in an 'RFI' Request For Information to have designer explain this non-standard test and 'language'.

 

[EdStainless]

Is this a customer standard? I have never seen that wording either.
I have seen specifications that set limits on the deposition rates, in other words that limit how thick or thin the test bead can be.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

 

[DekDee]

It is BS/EN terminology

" 'Recovery' is the weight of weld metal deposited in the weld relative to the weight of the core wire. Over 100% means that the weld will weigh more than the weight of the core wire. In other words the coating contains iron powder (or in some rods other alloys)."

I still cannot understand how you achieve "maximum electrode recovery"
Would it be highest amps / volts versus lowest travel speed (as per manufacturers parameters) ?
Cheers,
DD

 

[kingnero]

Hereby attached is a screenshot from the standard.

This is the EN16725, about welding in the railroad infrastructure industry. The final draft has been sent for approval and publication, this will make the final version.
Abbreviations used are AMS: austenitic manganese steel, which is basically Hadfield steel (13%Mn)
RA: railway authority
MMA and FCAW: well known I guess

My part in all of this is, as a welding engineer, to write the WPS'ses (different filler metals, different processes) according to this standard (from executing all tests, from a single bead test to in-track testing for several months, including geometrical tolerances of the weld, to the procedure qualification, to the final WPS).

As I said before, I do know what recovery is, but I cannot apply this in this particular phrase. I'm already glad that native English speakers also have problems with this... Means I'm not the only one.

I'll try an RFI, and keep you guys updated.
In the meanwhile, other suggestions are still appreciated!


EDIT: in another, similar, standard, the same can be found, but slightly different worded.
For MMA only, the deposit shall be made to maximum electrode recovery using the manufacturer's parameters.

 

[NBrink]

Total shot in the dark here, but I take it as:

The assessment shall be done with a sample prepared according to the electrode manufacturer's recommended parameters for maximum electrode recovery.


See what they come back with though...

 

[kingnero]

I have had no response from the secretary of the workgroup,
but one of the members told me the following:

When you weld a stick welding rod, you always have a part that you have to throw away (the "stub"). When welding stainless for instance, the stub is bigger because the overheating of the rod, and the loss of quality due to the burning of the alloying elements in the flux.

The above mentioned phrase means that you should weld as much as possible, thus with a stub loss as small as possible.

Never encountered a similar phrase, but this is what I was told...

 

[gtaw]

Another day and one more thing to learn.

Communication can be difficult even when we speak the same language. I took a course that used a text book titled "Plain Rhetoric Please." The lesson it taught was to speak or write using plain language and common terminology. It is a lesson that is sometimes lost on those tasked with developing codes and standards. When all is said and done, the document serves little purpose if no one understands what is written or if it is open to many interpretations.


Best regards - Al