... semi trailer axle are available, such as BPW type axle, American axle, inboard drum axle, outboard drum axle, Spoke axle(spider axle), concave axle, low ... bolton),3)suspensions (bogie, spoke bogie, American suspension and German suspension etc),4)axles (American and German, BPW type ... and FUWA type,spokeaxle, low loader, concave axle),5) ...