1. Nitrogen Cooling for high speed extrusion of Aluminium 7020 Alloy
Industry Forum – 29th March 2009
Nitrogen Cooling for high speed extrusion of Aluminium 7020 Alloy
Eng. Tommaso Pinter, ALMAX-MORI Srl (Italy)

2. Schedule (15’)
Introduction
7020 Aluminium
Nitrogen Cooling
Case Study

3. Overview Asset ALMAX June 2004 as Almax–Mori S.r.l.
ALUMAT as Alumat S.r.l.
Networked Organization
Turnover
16.000K euro/year – 2 production sites
Experience
Direct-Indirect Extrusion
Soft and Hard Alloys
Export (50%)
Europe, Middle East, Africa
Prod. Capacity
800 dies/month

4. Custom Solutions
Butterfly Die™
Insert Die
Nitrogen Cooling

5. EN AW-7020 Alloy

6. Case Study Process Parameters To Improve Low Productivity
25MN Direct Extrusion Press
Specific Pressure: 72 Kg/mm2
Alloy: EN AW 7020
Profile Application: Rail Transport
Exit Temperature: Up to 620°C
To Improve
Low Productivity
Short Die Life
High Scrap Percentage

7. Hot Work Tool Steel

8. Liquid Nitrogen Cooling
The INCAL® unit by MESSER provides cooling of the die by liquid nitrogen and guarantees that the nitrogen enters into the die at constant temperature and pressure.
N5Nitrogen by A.T.E. UNO INFORMATICA works manually the first time a die is used to setup all the parameters. Once the parameters have been settled, all data can be stored making a “photo” of all PLC parameters to be re-used automatically for the following extrusion runs.

9. The DIE

10. Comparisons Exit temperature: 540°C Previous: Over 600°C
Without Nitrogen Cooling the mandrel Broke After 12 billets
With nitrogen cooling we have Incipient Cracks after 30 billets
Exit temperature: 540°C
Previous: Over 600°C
RAM Speed: 3mm/sec
Previous: 2 mm/sec

11. Results

12. Best Practices Focus Design on Die Performance
Consider Nitrogen Cooling in designing Welding Points and Web Geometry
Be Sure to have Liquid Nitrogen at the Die
Use a Nitrogen Management Software
Double Slot for Liquid Nitrogen to balance nitrogen flow in die and mandrel

13. Almax-Mori & Alumat
Almax-Mori S.r.l. Via Matteotti Mori (TN)
Alumat S.r.l. Via Lisbona Ciserano (BG)