Looks cool, Dave :-)

qu' est ce ?

An auger is used to move particals of one type or another.
The auger flight rotates within a tube moving particals from one end to the other.
An example of this would be loading grain to a trailer from a storage facility.

What you can see in the photo is a very small section of the flight.
These can be many metres long. the flight spirals around and is fixed to a central shaft.

ok .merci dave , je comprends mieux !!

Great detail.

A spiral that reveals the passage of some laborious years. All the best, Anton.

Superb capture!

Cette texture de métal rouillé est bien mis en valeur bonne journée.