electrode efficiency

Date 02-06-2011 09:47 Edited 02-06-2011 09:54

Dear All,

In EN BS standards related to welding procedure there is a term of Run-out length of the Electrode and this related to the efficiency of the electrode ,I attached photos of that page,
my question is :how we can calculate the efficiency for each electrode we are using so we will be able to choose the correct efficiency table ? for calculation of heat input I already have the equation .

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By Metarinka (****)

Date 02-13-2011 18:01

can you give more information, I'm a little puzzled by what exactly is being asked here.

It's also note clear what process this is. In GMAW electrode stick out or run-out length is the distance between the tip that energizes the wire and the work piece. In GTAW electrode stick out is the distance from the tip that energizes the tungsten and the tip of the tungsten.

I've never seen either used to calculated arc efficiency. We've done quite a lot of research into arc efficiency calculations if you give some more information perhaps I can solve your question.

By doyenofcastle (**)

Date 02-14-2011 03:52

I can send the standards to you if you want but this efficiency related to SMAW run out length here is the lenght of the electrode after melt ex.450mm electrode can give 300 mm lenght after melt or different lenght ,actually this BS En standards I didn't find that in AWS but my client want me to prepare WPS for rebar using this standard I need to calculate this lenght ,in the photos attached there is heat input r arc energy and electrode run out length and electrode diameter but title of the table is ( efficiency of the electrode ) .may be this related to the lenght of the electrode after melting or there is equation to calculate the lenght .BS is difficult from AWS ,BS for professional .

By andy

Date 02-14-2011 11:33

Efficiency in this case is related to how effiicient the electrode is at depositing weld metal compared to the core wire. Simply put, some metal is lost in the slag, some as fume. These are <100% efficient. Others have iron powder in the coating and will deposit more weld metal than is in the core wire. These are more than 100% efficient. Sometimes called recovery and manufacturers data will tell you what the recovery is -

http://products.esab.com/Templates/T041.asp?id=53612

http://products.esab.com/Templates/T041.asp?id=58388

BS EN ISO 17660-1 is applicable to the welding of weldable reinforcing steel and stainless reinforcing steel of load-bearing joints, in workshops or on site. It specifies requirements for materials, design and execution of welded joints, welding personnel, quality requirements, examination and testing.

BS EN ISO 17660-2 is applicable to the welding of weldable reinforcing steel and stainless reinforcing steel of load-bearing joints, in workshops or on site. It specifies requirements for materials, design and execution of welded joints, welding personnel, quality requirements, examination and testing.