• Bear heavy static and dynamic loads of locomotive car‑body and bogie frame under heavy‑haul working conditions
• Attenuate strong wheel‑rail impact and high‑frequency vibration generated by heavy‑load operation
• Transmit huge longitudinal traction/braking forces as well as lateral & vertical forces between car‑body, bogie and axle‑box
• Realize elastic positioning, permit controlled deflection for reliable curve negotiation
• Limit car‑body rolling displacement via side‑bearing rubber pads; suppress structural‑borne noise
• Protect bogie, traction motor and other key assemblies, extend overhaul cycle and service life