50022 Concerns over maintenance of one steam locomotive

May 2011 in Heritage Rail

Knowledge Skills and experience Method of working South East

Concerns over the maintenance of steam locomotive 'Calbourn 24' have been expressed by a reporter.

This locomotive is believed to have several defects which include:

• The eight spring hangers on this engine do not pivot backwards and forwards as they should. This could lead to damage to the spring ends or to the spring hangers themselves, resulting in a stress fracture which could cause them to break.
• The brake shoes are wearing the wheels on this engine down below 'scrappage' level. They are flanging on the edge of the wheel instead of on the surface of the wheel. This is making the brake shoes less efficient.
• The brake pump was not checked or overhauled before it was put into the engine, even though the reporter believes the pump had sat unused in someone's garden for over a decade. The pump has been seen leaking oil and steam from various places.
• The buffer is broken and can be moved by hand. The reporter is under the assumption that it should only move under the weight of 30 tonnes.

The reporter is aware that individually these defects are not serious. However, if they were to fail at the same time, or if one was to initiate a chain of events that led to the rest failing, this could cause a derailment.

Could the Isle of Wight Steam Railway please:

• Inspect the locomotive?
• Repair and overhaul it where necessary?

Response from Isle of Wight Steam Railway

It is company policy that the locomotive 'Calbourne' numbered 24 is maintained and repaired in accordance with standards, outlined in the current Company's Safety Management System. These standards are largely based on the those of the former 'British Railways' (MPII), and current 'Rail Track' (MT276), where appropriate. The defects causing concern listed in your report have been inspected and the following points are noted.

• The eight spring hangers on this engine allow sufficient pivot movementbackwards and forward to allow the springs to deflect without putting strainon the hangers, brackets or springs. This movement is very small and as faras can be determined, the design has not been modified since the engine wasbuilt in 1891. Spring breakages are rare on this engine andwould be very unlikely to cause a derailment.
• The driving wheel tyre thicknesses are between 42.1 mm and 41.9 mm andtherefore not below the scrapping thickness allowed by Railtrack StandardMT276 for steam locomotives on the Main Line. The brake blocks areoverhanging the outside edge of the tyre but surface contact with the tread ismore than adequate for brake forces to be unaffected. The braking system is examined at 13-15 day intervals for defects in this area, and corrective actionwill be taken as and when necessary.
• The brake compressor was checked for condition and re-fitted following the
  major boiler work to engine in 20I0. It had previously been overhauled in
  2003, following years of covered storage since being sold to the railway in
  the 1960s. Minor steam leakage from spindle glands and oil leakage from
  displacement lubricator drain do not affect the reliability or efficiency of the
  compressor, which performs in accordance with the manufacturer's system
  requirements.
• The buffers are of the self-contained type and are bolted on to the buffer
  beam with a wooden packing piece of approximately 25mm thickness to act
  as a shock absorber. On the rear buffers, this packing piece shows some
  signs of movement i.e. cracking of the paint around the edge, and will be
  monitored for any further deterioration. One buffer spring is showing signs
  of weakness in that it is unloaded when the buffer is fully extended, allowingthe head to be moved by hand, but it remains in a secure condition. Theoperation of all buffers on the engine was checked in normal serviceconditions and was found to be satisfactory. The situation will be monitoredat normal scheduled examination intervals, and corrective action taken where appropriate.