Good day, could any of the experienced colleagues dispel my doubts about the pump ( for DG pre lubrication) type at the link below:

https://www.macorporation.net/gallery.p ... %2021%20En

It seems to me that it is gear type, but in the picture can you see 3 rotors? so if is 3 this could be screw.
Could you settle pease?

some of the picture of this pump are as a attachment.

Hello ArturZ. My experience of positive displacement pumps with three elements usually have the driving screw in the centre with two scrolls on either side. In the photo, the position of the drive off centre and the depth suggests that you are right; it is an external gear pump. The part of the casting that looks like a third element may be part of the relief system (?)

Thank you