# Thread: Optimal Angle of the Screw

1. Join Date
Mar 04
Posts
4

## Optimal angle of the screw

I want to know what the optimal angle of the screwblade is. Can you calculate this angle or are there different factors where the angle depends on.
Does the flight have something to do with that?

2. Join Date
Nov 00
Posts
2

## Screw angel

The screw angel depende on the material to be transported.
I mean particle size , cohesion forces and so on.

3. Join Date
Mar 04
Posts
4
But are there tables where the optimal angle is given, or are there formulas to calculate this factor and where can i find that??

4. Hermann_Feise Guest
I take it that we are talking about the inclination of a screw conveyor and how it affects performance. Clearly running it level horizontally or straigth upwarts ist best. Any other inclination will give less feed efficieny. However, some inclination is permissible if needed. The maximum angle you can run a screw conveyor on depends on:
- the screw geometry (mainly outer diameter and pitch)
- the fill level
- the material being conveyed.

You may look for information on this in papers from Allan W Roberts, U. Newcastle, AUS or ask Lyn Bates to provide the reference for his book on screw conveying.