Conversion.
A northbound flask train stands in the centre roads at Workington on 7 June 1984. Between the two RBX barrier wagons is MJJ flatrol 550003 built in 1969 at Shildon. The TOPS codes for these wagons seemed to change frequently and were always a bit confusing to me. The batch that included 550003 (seen here) is often quoted in railway publications as XKB (until 1983 when they became air brake only and designated FNA). The TOPS panel on this picture is unclear but has obviously been overpainted to (possibly) FKB or FXB. This overpainting probably reflects the modification made to this wagon when it had a sliding cover added.
In the 1980s BNFL decided they wanted flasks to be covered. This gave an extra level of security but also weather protection. In the 1970s, radioactive contamination was occasionally detected on flasks in transit. The levels were extremely low, but one source of the contamination was thought to be rainwater flushing out small amounts of material from areas of the flask that were normally inaccessible. Keeping the flasks dry also ensured nothing could be flushed off the wagon.
The new design of stainless clad FNAs were introduced in 1984 but - as an interim measure - older open, steel framed wagons like this one were converted, with the new girder work to support the sliding cover clearly visible here. Also, note the fillet inserted to block the gap between the sliding cover support girder and the floor of the well.
Conversion.
A northbound flask train stands in the centre roads at Workington on 7 June 1984. Between the two RBX barrier wagons is MJJ flatrol 550003 built in 1969 at Shildon. The TOPS codes for these wagons seemed to change frequently and were always a bit confusing to me. The batch that included 550003 (seen here) is often quoted in railway publications as XKB (until 1983 when they became air brake only and designated FNA). The TOPS panel on this picture is unclear but has obviously been overpainted to (possibly) FKB or FXB. This overpainting probably reflects the modification made to this wagon when it had a sliding cover added.
In the 1980s BNFL decided they wanted flasks to be covered. This gave an extra level of security but also weather protection. In the 1970s, radioactive contamination was occasionally detected on flasks in transit. The levels were extremely low, but one source of the contamination was thought to be rainwater flushing out small amounts of material from areas of the flask that were normally inaccessible. Keeping the flasks dry also ensured nothing could be flushed off the wagon.
The new design of stainless clad FNAs were introduced in 1984 but - as an interim measure - older open, steel framed wagons like this one were converted, with the new girder work to support the sliding cover clearly visible here. Also, note the fillet inserted to block the gap between the sliding cover support girder and the floor of the well.