As an addition to the recent researches, I am also working on extrusion of beams.
I will research PP and HDPE on 3 different temperatures and 3 different speeds to see what works the most efficient.
With all the samples I will do a deflection test to see if these setting changes the stiffness and quality of the beams.
The extruder runs with a gearbox slowing down the motor with a factor 10. At 50 Hertz, the motor turns 1380 RPM. So the extruder runs at 138 RPM.
I will run the extrusion on 15, 30 and 50 Hertz which results in 41.4, 82.8 rpm and 138 rpm
The temperatures I will use are: 160-170, 180-190, 200-210 for PP and 140-150, 160-170, 180-190 for HDPE
Each test will take 1 hour: resulting in 3*3*2=18 hours of testing.
The tube is use is 2 meters long and 50X50 mm with 4 mm walls.
@rorydickens
Actually, I ran out of time. Also, this is connected to a future project (read Pilot part) in Bangladesh where there is little PS available.
Precious Plastic will probably do further research to see if you can extrude PET.
LDPE beams, would require an extreme amount of plastic bags, something we were not ale to collect in this short amount of time
Nice work! Great to have a value for the Young’s modulus. But can you explain how you calculated E from the deflection? I get lost at the moment of inertia.
Also you seem to have different values of E when using different weights, is there some plastic deformation occurring?
Hi folks,
After many beams extruded I have some new data. All the beams were extruded with the extruder from the picture. And I used metal tubes which I mentioned in the start of the topic. While extruding I put a small wooden block in the tube (loosely fitting) to create a bit of counter pressure, resulting in smoother beams.
I updated the spreadsheet with my findings.
I did also stiffness estimations of all the beams finding higher speed gives more pressure which gives higher density of the beams which gives higher stiffness (E modulus)
Together with the visual qualities I figured that the most ideal settings for the extrusion are:
PP
Temperature: 180 barrel and 190 nozzle
speed: 50 hz-138rpm
Gives an E modulus around 1.0 GPa
HDPE
Temperature: 160 barrel and 170 nozzle
speed: 50 hz-138rpm
Gives an E modulus around 0.7 GPa
Discussion:
I was running low on material, (yes even in the PP headquarter). So, I did use a recycled PP from the industry. This material got less fluid while heated than the PP shreds I did shred myself. This can result in some variations in my research. How ever, the advised speed and temperature do still count for the extruder I used in the environment I was working
