Abstract: A rotor bearing having a rolling bearing raceway in an unhardened core region of a rolling bearing ring element that further includes an outer layer hardened to a surface hardening depth wherein the rolling bearing raceway is formed by a roll, wherein a diameter of the roll is 8 to 25 times the surface hardening depth.

Abstract: An interchange apparatus for a pneumatic conveying system including a plurality of branch tubes joined together at an acute angle in an interchange chamber to form a main tube and a flap positioned between at least two branch tubes of the plurality of branch tubes at the end of the interchange chamber, the flap faces the branch tubes and is swivelable between a first position and a second position. The flap is held in each position by a holding device such that when the flap is positioned in the first position there is a connection between a first branch tube and the main tube, and when the flap is positioned in a second position there is a connection between a second branch tube and the main tube. In one embodiment the flap is switched from a first position to a second position by the passage of the cylindrical objects through the interchanges.