BS AU 1C:1989 pdf free download.Specification for Dimensions of 50 fifth wheel king pin for semi-trailers.
1 Scope and field of application
BS AU 1C specifies the dimensions of the 50 50,8 mm (2 in)I fifth wheel coupling pin which is used for coupling semi-trailers to prime movers, taking into account the limitations of weight
generidly laid down by offici& requirements.
NOTE If. for extra heavy-duty vhicIe. thiacoupling pin is not sufficient, an 90 i 89 mm (35 in)I fifth wheel coupling pin according to ISO 4086 shall bt’ used.
In addition, BS AU 1C specifies the dimensional characteristics necessary for mounting and interchangeability.
2 Reference
ISO 4086, Road i’ehiclcs — 90 semi-trailer fifth wheel coupling pin — Basic and ,nountinglinterchangeabilitv di,nensions.
3 Basic functional dimensions of pin
4 Dimensional characteristics for mounting and interchangeability.