Compare deposited weld metal with welding consumable consumed to calculate deposition efficiency, material loss and consumable requirements.
Deposition efficiency measures how much of the welding consumable actually becomes useful deposited weld metal.
Some consumable can be lost during welding through mechanisms such as spatter, slag, electrode stubs and other process-specific losses.
For example, if 8.5 kg of weld metal is deposited while 10 kg of consumable is consumed:
The calculated deposition efficiency is therefore 85%.
Consumable loss is the difference between the total consumable used and the useful weld metal deposited.
Using the 8.5 kg deposited and 10 kg consumed example:
This represents 15% of the consumable consumed in the example.
The calculated efficiency can also be used to estimate how much consumable is required to produce a specified amount of deposited weld metal.
If deposition efficiency is 85% and the job requires 100 kg of deposited weld metal:
Approximately 117.65 kg of consumable would be required at that measured efficiency.
Different welding processes can have different deposition efficiencies. The actual result depends on consumable type, operating parameters and welding technique.
| Process | General Efficiency Consideration | Typical Loss Sources |
|---|---|---|
| SMAW / Stick | Often lower than wire-fed processes | Electrode stubs, slag and spatter |
| GMAW / MIG / MAG | Often relatively high | Spatter, wire starts and process losses |
| GTAW / TIG | Highly dependent on filler technique | Filler handling and process losses |
| FCAW | Varies with wire and process | Slag, spatter and process losses |
| SAW | Often high under suitable conditions | Flux and process-related losses |
A measured deposition efficiency is normally more useful for production planning because it accounts for actual welding conditions.
To measure it, weigh the consumable before and after welding and separately determine the mass of weld metal deposited.
For consistent results, the measurement period should be long enough to represent normal operating conditions and should account for all consumable used during that period.
Deposition efficiency directly affects consumable cost. A lower efficiency means more consumable must be purchased to produce the same amount of deposited weld metal.
For example, producing 100 kg of deposited weld metal requires approximately:
The difference can become significant on large welding projects.
A reduction in deposition efficiency means more material is required for the same deposited weld volume.
Consumable waste can also increase handling, storage and disposal requirements.
For production work, improving process efficiency can therefore affect both direct consumable cost and overall welding productivity.
Deposition efficiency compares deposited weld metal with the consumable used to produce it.
Under a properly defined measurement, deposited consumable mass cannot be greater than the consumable mass consumed.
If a calculation produces a result above 100%, check the weighing data, units, measurement boundaries and whether material from another source was included in the deposited mass.
This calculator measures deposition efficiency, meaning the relationship between useful deposited weld metal and welding consumable consumed.
It is not a complete welding-process efficiency or electrical arc-efficiency calculation. Those are different engineering concepts.
How do I calculate weld efficiency? Divide deposited weld-metal mass by consumable mass consumed and multiply by 100.
What is a good welding deposition efficiency? There is no single value that applies to every process. Efficiency varies by welding process, consumable, transfer mode and operating conditions.
Why is deposition efficiency lower than 100%? Some consumable can be lost through spatter, slag, electrode stubs and other process-specific losses.
Can welding efficiency be over 100%? A properly defined deposition-efficiency measurement should not exceed 100%. A result above 100% indicates a measurement, unit or calculation problem.
How much consumable do I need for a target weld? Divide the required deposited weld-metal mass by the deposition efficiency expressed as a decimal.
Does stick welding have lower efficiency? SMAW can have greater consumable losses than some continuous wire processes because of electrode stubs, slag and spatter.
Does deposition efficiency affect welding cost? Yes. Lower efficiency means more consumable is needed to produce the same deposited weld-metal mass.
Is deposition efficiency the same as arc efficiency? No. Deposition efficiency concerns consumable-to-deposited-metal conversion. Arc efficiency concerns the portion of electrical energy transferred effectively to the workpiece.
Can this calculator compare two welding processes? Yes. Calculate the measured deposition efficiency for each process and compare the resulting consumable requirement for the same target deposited weld mass.
What should I do if my measured efficiency seems wrong? Check that deposited metal and consumed consumable were measured over the same period, use identical units, and account for all relevant consumable losses.