Aluminium welding wire can be fed reliably from a bulk drum to a welding robot over 20 m and more – if the conduit causes as little friction as possible and the wire is pushed rather than pulled. MIGAL.CO combines roller-guided Rolliner conduits (friction coefficient 0.08 instead of 0.20 for sliding liners) with the RoboFeed feed assist, which allows conduit lengths of more than 50 m between drum and robot.
Why is aluminium wire difficult to feed?
Wire feed systems were originally developed for steel wires, which glide well and are stiff. Aluminium wire is soft and glides poorly – AlSi and pure aluminium wires in particular. Three effects add up:
- Friction grows exponentially with every bend. The pulling force behind a conduit follows the Euler–Eytelwein formula Fout = Fin · eμ·α, where μ is the friction coefficient of the conduit and α the sum of all bending angles in radians.
- Pulling brakes itself. Aluminium wire must never be pulled through a long liner – the higher the pulling force, the harder the wire presses against the liner wall.
- Twist and cast. Wire is drawn vertically out of a drum, which twists it. Without a decoiling aid, 5000-series alloys in particular tend to form knots. Wire from small spools has a tight cast that makes the wire tip circle at the contact tip.
How much force does the conduit need?
Worked example for a MIGAL.CO Jumbo drum with decoiling aid (extraction force 1.0 N) – theoretical force at the end of the conduit for different total bending angles:
| Total bending angle | Sliding liner (Softliner, Duroliner, μ = 0.20) | Rolliner (μ = 0.08) |
|---|---|---|
| 360° | 3.5 N | 1.7 N |
| 720° | 12.3 N | 2.7 N |
| 1080° | 43.4 N | 4.5 N |
| 1440° | 152 N | 7.5 N |
If the wire feeder can permanently pull 30 N, a sliding liner theoretically reaches its limit at about 970° of total bending; the Rolliner at about 2,400° – roughly two and a half times as much. These are theoretical limits: for safe continuous operation we recommend planning with about half of them, i.e. about 500° for a sliding liner and about 1,200° for the Rolliner. You can check your own layout with our calculator on the basics page.
Which solution for which layout?
| Layout | Recommended solution |
|---|---|
| Drum right next to the wire feeder, short and straight connection | Softliner (static) or Duroliner (robot movement); keep the conduit as short as possible |
| Longer route with several bends, up to 25 m per conduit | Rolliner 3G for wire up to 1.6 mm, Rolliner XL2 up to 4 mm; no tools needed for shortening or extending (Rolliner NG is supplied as a spare part for existing installations only) |
| More than about 20 m or many bends, or very soft wire | RoboFeed feed assist: 100 W drive, feed force up to 165 N, 0–50 m/min, conduit length of more than 50 m, no electrical connection to the robot or power source required |
| Additionally monitor wire consumption | RoboFeed WireManager: remaining-wire warning (signal, e-mail, SMS), automatic threading, barcode check of the wire pack |
| Compact pneumatic alternative | Pneumatic feed assist DLDA-1: approximately doubles the permissible bending angle; 0–30 m/min, 0–60 N |
Product pages: Softliner and Duroliner, Rolliner 3G, Rolliner XL2, RoboFeed, RoboFeed WireManager, Pneumatic feed assist DLDA-1.
What matters at the drum?
- Decoiling aid: ASH 81 for Eco drums, TOU400/580 for Jumbo drums – prevents knots and keeps the extraction force at 1.0–1.5 N.
- Drum hood and connector: guide the wire into the conduit without additional friction.
- Wire end control DES-2: a non-contact sensor reports the end of the wire before the robot runs empty.
- Straight wire: for long, visible seams the RoboStraight wire straightener with 14 rollers removes the remaining cast.
Practical example: Bär Cargolift
Bär Cargolift welds aluminium tail lifts on Cloos robot cells with S Al 5183, 1.6 mm. The wire used to come from 40 kg B-400 spools placed close to the wire feeder; the tight cast caused circling wire tips and rework, and changing heavy spools at height was laborious. Together with MIGAL.CO, Bär switched to 240 kg Jumbo XL drums with RoboStraight, RoboFeed and Duroliner conduit over a distance of up to 20 m. Result: straight seams, no abrasion in the feed system, less rework and fewer drum changes. After several weeks of testing, four welding stations were equipped. Read the full report.
Frequently asked questions
How far can aluminium wire be fed from a drum?
With a Rolliner conduit up to 25 m per section (extendable); with the RoboFeed feed assist more than 50 m.
Does RoboFeed need a connection to the robot controller?
No. RoboFeed stops by itself when the main wire feeder stops and delivers the required wire amount when it runs. A 24 V interface for start/stop and wire inching is available.
Can a Toughliner be used for aluminium?
No. Toughliner is designed for steel wires only; for aluminium use Rolliner, Softliner or Duroliner.
Which drums does MIGAL.CO supply aluminium wire in?
Eco drums from 80 kg, Jumbo drums 140 kg and Jumbo XL drums 240 kg, depending on the alloy – see the aluminium welding wire data sheets.