vacuum extruder pump

[specmario]

Could somebody help me, how to calculate optimal suction power of vacuum pump for rubber blend degassing. It is 120mm extruder, common rubber blends on the base of NR, IR, SBR and carbon black filled.
Thank you.

 

[GrahamBennett]

I trust you or your compounder are keeping your ingredients as dry as possible before mixing and you have included calcium oxide (desicant) in the compound to minimise the moisture content of the mixed compound. I have found that it is not always necessary to use a vacuum - just vent to atmosphere is often sufficient for degassing. In any case, I would never apply more vacuum than necessary because of the additional costs in generating vacuums. I have always worked on a trial and error basis to determine what vacuum levels are necessary, which might be different in different batches of the same compound.

 

[specmario]

Thank you. We will see. I'm going to order vacuum pump with liquid ring with suction power upto 15-20m3/h and pressure max. 100mBar. I hope, it's a good choice.