Working draft amendment to UN R55 with regard to speed reduction, speed dependence, and heavy transports
Document R55-13-07/Rev.1
4 April 2016

Working draft proposal of the UN R55 informal group for a uniform procedure to rate couplings for extreme heavy transport configurations based upon a speed-reduction method. The intent is to address conditions where there are no coupling products with appropriate certified performance values.

Status: Superseded
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Previous Documents, Discussions, and Outcomes
5. | Discussion of open items

Item 20 (Heavy transports) (R55_02­­_13, R55_04­­_08, R55_04­­_12, R55_05_01, R55_05_06, R55_05_20, R55_05_21, R55_05_22, R55_07_18, R55-08-13, R55_09_06, R55_10_08; R55_10_09; R55_10_13; R55_13_07; R55_13_08)
Since last meeting Mr. Svensson had augmented the proposal to include a lower limit for reduction. This limit had two components. The reduction is proposed to be linear from 80 km/h to 36 km/h ending at a maximum requirement reduction of 33%. On top of that a requirement on D-value corresponding to startability in 15% ascent. In general the concept got good acceptance. Some comments stressed the importance that the proposal does not apply in off-road applications. Mr Svensson pointed to the option to do away with the upper limit on speed. While the reference speed is still 80 km/h an increase in allowable maximum speed to let say 90 km/h would result in an increase in the requirements. There were some comments on application to exceptional transports only. That of course is a given as this is under the heading “Special operations”. The agreement reached was that all manufactures of coupling shall evaluate the proposal towards exemption certificates for heavy transports that they had issued hitherto. These evaluations shall be reported to Mr. Svensson who will compile the results. The compilation will be on the form xx% of the exemptions would have been safely handled through the proposed formalism. On the basis of this compilation a mail vote would judge whether to take this proposal as a working document to GRRF-82 or not.

Item 21 (Limiting cases for the usage of certified characteristic values) (R55_04­­_11, R55_05_05, R55_06_09, R55_07_06, R55_07_14, R55-08-03, R55-08-04, R55-08-05, R55_09_04, R55_09_05, R55_09_11, R55_09_ 13, R55_10_03: R55_10_04; R55_10_05; R55_10_06; R55_10_07; R55_10_08; R55_10_15, R55_11_ 12; R55_11_13; R55_11_15; R55_12_03; R55_12_10; R55_12_20; R55_12_28; R55_13_07; R55_13_08 )
This proposal had been endorsed at the GRRF-81. A small change was made to the proposal in that the definition of a dolly was aligned to the definition agreed in the IWG-MVC. The definition was challenged by Mr. Westphäling saying that the word “dolly” was originating from Germany and meaning a rear axle group of extreme long cargo transports. After some discussion it was agreed to investigate the use of converter dolly instead of just dolly. Several experts were skeptic. [Since the meeting the secretary has made some investigations to find out the risk for misinterpretation. That risk was found to be very low. Hence he proposes to go forward with the word dolly without any word “converter”. ] One further minor change was made to Annex 6 §3.6.1 to align that paragraph with the changes made in the definition part of the regulation. With these changes it was agreed to go forward with this proposal as a working document for GRRF 82.

Related and Previous Documents
R55-13-25
Relates to UN R55 |