Changes

The basis of this type is a design by the London and South Western Railway, first introduced in 1903. Further builds for BR took place in 1954Featuring a large hopper with slab sides, each with 7 vertical ribs, 1971-1974 and 1980-1982. Apart from the bogies there were only minor changes between the oldest and the newest buildstype has three discharge chutes, a testimony one to the soundness outside of each rail and one in the original designcentre. Depending on braking arrangements, wagons were designated YGV Walrus (vacuum braked only), YGH Sealion (dual vacuum/air braked) or YGB Seacow (air braked only but with At each end of the addition of wagon is a vacuum through pipe). Those control platform with vacuum piping removed were reclassified YGA. The SVR vehicles formed part three large handwheels to control each of the last build of Seacows, Lot number 3966, production of which began at Shildon and was transferred to Ashfordchute doors.

Featuring a large hopper with slab sides, each with 7 vertical ribsFurther builds for BR took place in 1954 (Walrus), 1971-1974 (Sealion and Seacow) and 1981-1982 (Seacow). Apart from the bogies there were only minor changes between the oldest and the type has three discharge chutesnewest builds, one a testimony to the outside soundness of each rail and one in the centreoriginal design. At each end Depending on braking arrangements, wagons were designated YGV Walrus (vacuum braked only), YGH Sealion (dual vacuum/air braked) or '''YGB''' Seacow (air braked only but with the addition of the wagon is a control platform vacuum through pipe). Those with three large handwheels vacuum piping removed were reclassified '''YGA'''.  ==Service==In 1981 BR introduced Design Codes to control each replace the former Diagram number system, with the final build of Seacows in 1981-82 being the chute doorsfirst wagons to receive such a Design Code (YG500H). This last batch present presented a slightly different appearance as the hopper body was now primarily welded instead of rivetted and the vertical ribs were formed of box rather than U-sections. The wagons are were mounted on more modern Y27CS bogies with roller bearings. All six of the SVR's examples came from this batch, of which DB980000-DB980244 formed Lot 3966 and DB980245-DB980250 formed Lot 4010. Construction began in March 1981 (although the works plate of one the SVR's examples, DB980015, bears a 1980 date). Production began at Shildon and was transferred to Ashford. The majority of this build went to MAINLINE with others going to TRANSRAIL and a smaller batch to LOADHAUL<ref>[[Bibliography#Other References|Larkin Vol 3 (2013), pp. 1, 10.]]</ref>.

!Number !! Originally built !! Originally built by!! [[TOPS code]] !! Notes

| DB980015|| 1980 || BR Shildon || YGB || Spare, not in use. Lima have produced an OO gauge model of this vehicle

| DB980083|| 1981 || BR Shildon || YGB ||

| DB980098|| 1981 || BR Shildon || YGB ||

| DB980142|| 1981 || BR Shildon || YGB ||

| DB980220|| 1981 || BR Ashford || Painted with code YGA||

| DB980239|| 1981 || BR Ashford || Painted with code YGA||

DBS Cargo locomotive 66068 delivered the Seacows from Bescot to the SVR on 10 March 2017. The final TOPS code painted on each wagon is shown above. As delivered from DBS Cargo the vacuum brake fittings were removed or disconnected.