of the thrust flanges 76 bear against the sides of the portions 40 and 42 at the cavity locations radially projecting anti rotation flanges 84 extend between the opposite thrust flanges 76 at the ends of the inserts 70 the flanges 84 are connected to and extend radially outwardly from the thrust flanges 76 and the central rib 74 as best seen in fig3 each pair of anti rotation flanges 84 is received in the corresponding anti rotation flange receiving area 64 at the joint to secure the inserts 70 in the cavities 50 and 52 and prevent rotation of the inserts relative to the bearing block assembly the rib 74 and the flanges 76 strengthen the inserts and help secure the inserts against axial movement relative to the bearing blocks a rounded or arc shaped notch 90 is located in each anti rotation flange 84 adjacent each end of the rib 74 the notch 90 conforms to a rounded wall portion 94 adjacent the bolt receiving bore 62 and also helps to locate and secure the inserts in the cavities referring to fig4 the half section 40 and similarly the half section 42 includes a central groove 104 conforming to and receiving the corresponding rib 74 of the insert 70 the groove.