Aluminium Wire Drawing

 

Aluminium Wire Drawing Guide for Students

Introduction

Aluminium Wire Drawing is a manufacturing process in which an aluminium rod is pulled through a series of dies to reduce its diameter and produce wire of the required size. Aluminium wire is widely used in power cables because it is lightweight, cost-effective, and has good electrical conductivity.

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What is Aluminium Wire Drawing?

Wire drawing is a cold-forming process where an aluminium rod passes through progressively smaller dies.

Results:

• Diameter decreases
• Length increases
• Surface finish improves
• Tensile strength increases

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Raw Material

EC Grade Aluminium Rod

• Material: Electrical Conductivity (EC) Aluminium
• Purity: 99.5% or higher
• Standard Rod Size: 9.5 mm
• Conductivity: Approximately 61% IACS

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Process Flow

Aluminium Rod (9.5 mm)
          ↓
      Pay-Off
          ↓
  Rod Breakdown Machine
          ↓
 Intermediate Drawing
          ↓
     Annealing
          ↓
      Take-Up
          ↓
 Finished Aluminium Wire

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Main Machine Components

1. Pay-Off Stand

Holds the aluminium rod coil and feeds it into the machine.

2. Drawing Dies

• Tungsten Carbide Dies
• Diamond Dies (fine wires)

Used to gradually reduce wire diameter.

3. Capstans

Pull the wire through each die.

4. Lubrication System

• Reduces friction
• Increases die life
• Improves wire surface quality

5. Annealer

Softens the wire after drawing.

6. Take-Up System

Collects the finished wire onto reels or spools.

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Example Size Reduction Schedule

Pass	Diameter (mm)
Input Rod	9.50
Pass 1	8.60
Pass 2	7.80
Pass 3	7.00
Pass 4	6.30
Pass 5	5.70
Final	Required Size

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Types of Drawing Machines

Rod Breakdown Machine

Converts 9.5 mm rod to intermediate sizes.

Intermediate Machine

Further reduction for conductor manufacturing.

Fine Wire Drawing Machine

Produces small-diameter aluminium wires.

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Annealing Process

Drawing hardens aluminium.

Annealing:

• Restores flexibility
• Reduces brittleness
• Improves conductor performance

Types

• Online Annealing
• Batch Annealing

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Advantages of Aluminium Conductors

✅ Lightweight

✅ Lower Cost than Copper

✅ Easier Transportation

✅ Good Conductivity

✅ Widely Used in Power Distribution

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Common Wire Sizes

Diameter (mm)	Application
1.70	Small Conductors
2.50	Building Wire
3.50	Power Cable
4.50	Medium Conductors
5.00+	Large Power Conductors

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Quality Control Tests

Diameter Measurement

Using micrometer or laser gauge.

Tensile Strength Test

Checks wire strength.

Elongation Test

Measures flexibility.

Surface Inspection

Checks scratches, cracks, and marks.

Conductivity Test

Ensures electrical performance.

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Aluminium Wire Drawing – Production Issues, Reasons & Corrective Actions

Production Issue	Reason	Corrective Action
Wire Breakage	Excess tension, damaged die, poor lubrication	Adjust tension, replace die, improve lubrication
Diameter Variation	Incorrect die size, unstable machine speed	Verify die schedule, stabilize machine settings
Oval Wire	Misaligned die or capstan	Align dies and machine components properly
Surface Scratches	Worn or damaged die, dirty guides	Replace die, clean guides and rollers
Surface Marks	Contaminated lubricant, poor rod quality	Change lubricant, inspect incoming rod
High Die Wear	Poor lubrication, incorrect die angle	Improve lubrication and use correct dies
Low Conductivity	Poor annealing, low-quality rod	Optimize annealing parameters, check rod quality
Hard Wire	Insufficient annealing	Increase annealing current/temperature
Soft Wire	Excessive annealing	Reduce annealing temperature/current
Bird Caging	Improper take-up tension	Adjust take-up tension and winding settings
Wire Twist	Incorrect spool winding, machine misalignment	Align machine and optimize winding tension
Loose Winding	Low take-up tension	Increase spool tension settings
Cross Winding	Traverse mechanism malfunction	Check and adjust traverse system
Excessive Heating	High reduction rate, poor lubrication	Reduce reduction per pass and improve cooling
Black Spots on Wire	Burnt lubricant or contamination	Replace lubricant and clean system
Rod Slippage	Worn capstan or improper tension	Inspect capstan and adjust tension
Frequent Die Breakage	Poor die installation or overload	Install dies correctly and reduce load
Uneven Surface Finish	Die wear, poor lubrication	Replace die and maintain lubricant quality
Wire Vibration	Machine imbalance or excessive speed	Balance machine and reduce speed
Production Loss (High Scrap)	Frequent breakages and poor setup	Improve process control and operator training

Key Areas for Daily Monitoring

✔ Wire Diameter
✔ Surface Quality
✔ Conductivity (% IACS)
✔ Elongation (%)
✔ Tensile Strength
✔ Annealing Quality
✔ Lubrication Condition
✔ Die Wear Status
✔ Production Speed
✔ Scrap Percentage

Safety Precautions

• Wear PPE and safety glasses.
• Keep hands away from moving capstans.
• Ensure proper lubrication.
• Follow machine lockout procedures during maintenance.
• Inspect dies regularly.

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Applications of Aluminium Wire

6

Aluminium wire is used in:

• Power cables
• Overhead transmission lines
• Distribution networks
• Medium voltage cables
• Armoured cables
• Industrial power systems

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Conclusion

Aluminium wire drawing is a key process in electrical cable manufacturing. By drawing a 9.5 mm EC aluminium rod through multiple dies, manufacturers produce high-quality conductors used in power transmission and distribution. Proper lubrication, die maintenance, annealing, and quality control are essential for achieving reliable conductor performance.

Author:
RG Rana Gulfam Ahmad