Weld Consumable Calculator
Weld area, deposited metal and the electrode you actually need to buy.
Quick answer
With the default inputs: Weld type Fillet weld · Fillet leg size K 6 · Plate thickness 10 etc.Consumable required 24.7 kg
Edit the inputs below to recalculate.Inputs
Result
Consumable required
24.7kg
| Weld cross-section | 18.0mm² |
| Deposited metal per metre | 0.141kg/m |
| Total deposited metal | 14.13kg |
| Theoretical consumable | 23.55kg |
| Consumable with allowance | 24.73kg |
| Consumable per metre | 0.247kg/m |
| Consumable to metal ratio | 1.75× |
Fillet area uses the theoretical isosceles triangle (A = K²/2) with no reinforcement; real fillets are convex and deposit another 10-20%, so set the extra allowance to 15% for tight procurement. V-groove area is A = b·t + (t−p)²·tan(α/2). Deposition efficiency means kilos of metal deposited per kilo of electrode — about 0.6 for stick welding, the rest becoming stubs, spatter and slag.
Reverse: known result, work out one input
Enter a target result; the other inputs stay fixed and this one is worked out.
Formula
| Fillet area | A = K² ÷ 2 |
| V-groove area | A = b·t + (t − p)² × tan(α ÷ 2) |
| Metal per metre | m = A × 0.00785 (kg/m) |
| Total deposited metal | M = m × weld length |
| Consumable required | G = M ÷ deposition efficiency × (1 + allowance) |
A 6 mm fillet over 100 m at 60% deposition: 18 mm² section, 14.13 kg deposited metal, 24.73 kg of electrode — 0.247 kg per metre.
How to work it out
- Compute the weld cross-section. A fillet weld is a right triangle, so area = K²/2 for leg size K; a 6 mm fillet is 18 mm².
- For butt welds work from the preparation: a V groove is roughly b + (t − p)²·tan(α/2), though in practice the handbook tables are used.
- Deposited metal = section area (mm²) × length (mm) × 7.85 ÷ 10⁶, in kg.
- Consumable = deposited metal ÷ deposition efficiency × (1 + loss allowance). Covered electrodes run 55-65%, solid wire 90-98%, flux-cored 80-88%.
- Round up to packaging: 5 kg per electrode packet, 15-20 kg per wire spool.
Where it goes wrong
- Ignoring deposition efficiency — 35-45% of a covered electrode becomes slag and spatter, so using deposited metal as the electrode order undercounts by over 40%. This is the classic error.
- Computing a fillet as K × K — the section is a triangle of K²/2, and the square doubles the figure.
- Using one efficiency for electrodes and wire — 60% against 95% for solid wire and 85% for flux-cored is a 50% spread.
- Ignoring stubs — electrodes are unusable below 40-50 mm remaining, which is 5-8% of the length and belongs in the allowance.
Material and cost
J422 electrode 6-9 CNY/kg, J507 low-hydrogen 9-14, ER50-6 solid wire 7-11, flux-cored 12-20. Welding labour 15-40 CNY/m by weld type.
On site
- Low-hydrogen electrodes must be baked at 350 °C for an hour and held no more than four hours in a quiver, or hydrogen cracking risk rises sharply.
- Consumables are more than filler metal: shielding gas (0.3-0.5 kg CO₂ per kg of wire), power and grinding discs all belong in the cost.
- On thick plate with multiple passes, poor interpass cleaning traps slag, and rework far outweighs a few extra electrodes.
Basis
- GB 50661-2011 Code for welding of steel structures
- GB/T 5117-2012 Covered electrodes for manual metal arc welding of non-alloy and fine grain steels
- GB/T 8110-2020 Solid wires for gas shielded arc welding of non-alloy and fine grain steels
FAQ
Why is the electrode figure so much larger than the deposited metal?
An electrode never converts fully. In stick welding, stubs, spatter, burning flux and burnt alloying elements waste 35-45%, which is why deposition efficiency sits at 0.55-0.65 — only about 0.6 kg of every kilo lands in the joint. That is normal, not waste. CO₂ gas-shielded welding reaches 0.85-0.95 and saves nearly a third of the consumable.
How is the fillet leg size chosen?
From the thinner plate: equal to plate thickness below 6 mm, about 0.7× for 6-12 mm, and 0.5-0.6× above 12 mm, never below a 5 mm minimum. Both a code minimum (to avoid cold cracking) and a maximum (to avoid burning through thin plate) apply. Oversized legs waste consumable and widen the heat-affected zone and distortion.
How much electrode does a tonne of steelwork need?
Roughly 8-15 kg/t for ordinary portal frames and buildings, 20-25 kg/t for heavy joints with full-penetration welds, and only 4-8 kg/t for light purlins and space frames dominated by thin-plate tacks. The range is so wide it is only good for preliminary ordering — for real quantities multiply this calculator's per-metre figure by the measured weld length.
Cite this page
Use this format in reports, method statements or coursework. The link is permanent.
Building Calculator. Weld Consumable Calculator. 2026-10-25. https://jianzhujisuan.com/en/weld-material
Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.