Northern returns 195s and 331s
AFTER RECTIFICATION Northern has returned all but two of its Class 195s and 331s to service. The repair was applied to the T-sections of the yaw damper brackets, which connect the damper to the bodyside, that had broken in April. CAF led the investigation into the cracks, including instrumentation such as strain gauges fitted to set 195002 that demonstrated that excessive forces were only seen on powered bogies on the DMUS, and further investigations have confirmed that the cracking problem is not being seen on the electric sets.
These results have reduced concerns that the problem might affect Transpennine Express’s Cafbuilt Class 397 EMUS and Mk Va coaches and Caledonian Sleeper’s Mk V stock.
The solution for the Class 195s has been to fit a milled steel spreader plate between the yaw damper brackets for the powered bogies and the T sections. This distributes the load from the yaw damper more evenly. The work has been carried out on trains taken out of service with visible cracks, but the modification is expected to be used on the full Class 195 fleet.
The 43-strong Class 331 fleet was back in service by June 8 and just two Class 195s were awaiting attention, with 195020 still to go through nondestructive testing prior to modification and 195121, the first unit to show the cracking that led to the checks, which required the most extensive repairs.