Informal Group on Amendments to UN R55.01 | Session 12 | 14-15 Jan 2016
Paris
Agenda Item 5.7.
Item 25 (Articulation angles as installed)

Mr. Stokreef had elaborated the proposal from our October meeting. Mr. Stokreef was not present at the meeting. However we tried to do the best we could.

The first observation was that the measurement method, need to be further detailed. Comparing to the standard ISO11407 the dimensions of the drawbar itself need to be addressed in some way. Currently the proposal just refers to a straight line from the coupling point to measure the angles. It was then challenged what added value this proposal was giving as compared to the §1.3.4. Annex 7.

Looking then to the proposal for the fifth wheel couplings it was referred to the standard ISO1726-2. There the pivoting angles around a transverse axle is set to 3,5° towards the front and 4,5° towards the rear. We had also received comments from Volvo that the far from all semitrailers comply with any standard e.g. dimensions from 1230/2012/EU. This makes it hard to secure that this proposal will really give any major improvement. The manufacturers of fifth wheels also commented that the attachment bolts towards the mounting plate need to be disregarded when measuring the articulation angles for the fifth wheels.

The discussion was ended with a message to Mr. Stokreef to elaborate a bit more. Then consideration should be given to whether Annex 7 §1.3.4. could possibly be enough for drawbar couplings and whether something similar could be set up for fifth wheel couplings. Next meeting.

Documentation
R55-12-06 Minimum articulation angles for vehicle couplings
R55-12-07 Overview of coupling angles of rotation