A bent shaft can cause premature wear of the bearing lines, gearboxes and/or couplings, and in a worst case scenario can put the vessel out of service. In most cases, the primary option for resuming operations quickly and economically is to cold straightenthe shaft, rather than purchase a new one.
The Wärtsilä propulsion workshop in Denmark has developed a unique technique for cold straightening, and can repair shafts of all types and sizes. Many jobs can be completed within 24–48 hours from arrival at our workshop. Classification societies consider this Wärtsilä solution to be permanent, and an individual certificate is issued on each repair.
Cold straightening is performed using a hydraulic press, numerically controlled. This method does not affect the metallurgy of the shafts, it releases stress from the material, and allows full recovery of the geometry of the shaft with the same tolerances as for a new shaft.