Modifications - Vehicles and the evolutionary change

Once a vehicles has been built and is in service there are three basic maintenance operations that occur to retain the vehicle for traffic use

1. Routine or cyclic maintenance
2. Repair work
3. Modifications and improvements

In VR history many protocols were established to ensure vehicles were well maintained. In this day and age it would appear that it may have been a case of 'over servicing' but the times and the political envirnment need to be understood. VR was a government run railway and had a responsibility to maintain equipment in good order.

Routine or cyclic maintenance

By the 1970s the average vehicle lift was five years. Rolling stock in higher mileage traffic, such as carriages and express vehicles, the average was about three years. The 'lift' entailed an inspection of the underframe and body with repair work as required. Brake rigging and equipment was checked. When done, the vehicle was rolled out to the Paint Shop, given an overspray and lettered up for traffic. In the 1880s through to the 1900s, brake maintenance and some 'lifting' was done at local steam engine depots. I'm sure that as larger and larger vehicles were built this became more difficult. Brake equipment in service had a defined 'life' between overhaul. As vehicles were regularly checked, those found with 'expired' or 'brake overhaul due' dates were inspected. The two types of lettering for vehicle maintenance were:

• Brakes - PV or PV Due on the underframe was a reference for the brake 'Piston' and triple 'Valve' inspections. These exams were usually twelve to eighteen months apart.
• Lift - Up to about 1975 the date the overhual was conducted was painted on the underframe as 'xxxL m.yy' where 'xxx' stood for the location code of the work and the 'm.yy' was the Month and Year the work was done; example 'NL 6.70': Newport lift, June 1970. This required a knowledge of the lift period for the vehicle class. Some were two years, three years or fives years with service stock set to ten years. This reporting system was changed to reflect the Due Date whereby the lift period was added to the date the work was done. For the above example the lettering would become 'NLDW 11.75': 'Newport Lift', 'Due Workshops' on 'November 1975'.

Repair work

As in the case of any moving vehicle or traffic, damage to vehicles was a fairly common event. Not always related to derailments, damage to vehicles usually occurred in the following manner

• Loading or unloading damage to body, floor or doors
  • By cranes and forklifts with dropped or swinging cargo.
  • By trucks and road vehicles whilst engaged in loading/unloading
• Shunting accidents where
  • vehicles are side swiped or 'torpedoed' when not clear at the ends of sidings
  • vehicles rough shunted onto each other at higher than normal impact speeds
  • vehicles pushed or rolled over the ends of siding or into the solid objects such as buffers, end walls of sheds/platforms
• Derailment damage to sides, ends, doors, bogies, underframe when
  • Vehicle is involved in train collision
  • Vehicle is involved in serious derailment and leaves the track
  • Vehicle is involved in slight derailment and only wheels leave the rail with rerailing by engine or derail ramps by reversing direction
  • Vehicle is involved in slight derailment but suffers major damage when rerailed incorrectly
• Fire
• Metal fatigue where the vehicle suffers cracks or total support failure due to
  • Age of metal
  • Flexing of body in load/unload cycles
  • Fatigue cracks due to vehicle design change that alters the stree points on load members
  • Unauthorised welding or workmanship that causes the main structure to be weakened

In most cases, the damaged vehicles are transferred to a major workshop where they are stored in the yard until workshop time and money can be allocated for repair. Transfer could be as easy as attaching to an engine or train. Badly damaged vehicles were lifted onto other flat wagons or road transport for transfer. Vehicles severely damaged were 'written off' and scrapped, sometimes on site. All efforts were made to effect repair as this was generally cheaper than the construction of a replacement vehicle. This work was done after an assesment of cost and time. The work was then authorized.

Modifications and improvements

Modification work was usually carried out during the routine maintenance cycle. Only rarely will a modification be important enough for vehicles to be recalled as soon as possible for a modification change.

Modifications were generally done for the following reasons

• Vehicle age or design required modification

  In some cases the underframe or body was found to be under strength. Extra brackets, plates, gussets or internal steel straps were added to provide extra support to enhance strength. Swing door carriages were cross braced internally. GJX aluminium wagons were fitted with strengthening plates on account of underframe cracks. Z van bodies were strengthened with brackets at the cupola end.

  Sometimes the initial design just didn't properly so modifications were tried until success was achieved. The air pressure relief valves were placed onto the hoppers of FJ, FX, J and JX wagons were found to be clogging up. These were moved down to the air supply line.

• Technical advances that superceded equipment fitted to the vehicle.

  The technical changes over the years saw new equipment available on the market. In general, new vehicles in service were provided with new types of equipment if they could be integrated easily. If the equipment had significant maintenance saving then it was generally retro fitted to older equipment mindful of the initial purchase and fitting costs.

  Diaphram brake valves replaced the brass triple valve. 'Miner' handbrakes superceded the ratchet type and in later years replaced them.

• Introductions of new traffic and the vehicle could be suitably adapted for minimal cost

  This work was generally of a minor nature, restricted to container anchor brackets, rope lashing rails and side rope typing loops or bars as examples. Some flat wagons were fitted with removable bolster supports for traffic such as poles or pipes.

• Vehicle could be modified to improve operation safety ( train running, shunting work, loading/unloading )

  Fittings such as better end step design, safety stickers and handbrake levers.

• Internal fittings

  For passenger carriages and suburban stock internal seats and wall fittings were changed to suit newer fabric or hard wearing materials. Maintenance of these cars was quite high and newer materials allowed costs to be lowered.

Peter J. Vincent

April 2008, v5