ISO 4251-1 pdf download – Tyres (ply rating marked series) and rimsfor agricultural tractors and machines —Part 1: Tyre designation and dimensions,and approved rim contours.
This part of ISO 4251 estabhshes the designation in use and the dimensions of the ply rating maried series of tyras for agricultural tractors and machlnes
Tyre load ratings, rim dimensions, and tyre classification and nomenclature are given fl Iso 4251.2, ISO 4251.3 and ISO 42514 respectively.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition ol the referenced document (ilcluding any amendments) applies.
ISO 4223-1, Definitions of some terms used in the lyre industry — Part 1: Pneumatic tyres
3 Terms and definitions
For the purposes of this document, the temis and definitions given in ISO 4223-1 apply.
4 Marking
The marking of the ply rating marked series of tyres consists of the designation of tyre size and load rating, and any additional information. See 4.1 to 4.4.
4.1 Tyre size designation
The present size marking for the identification of tyres consists of the nominal tyre width code and the nominal rim diameter code.
5.2 Agricultural steering wheels — Tractor tyres
Tyre size designations, measurement rims, design dimensions of new tyres, and maximum tyre dimensions in Service are given in
a) Table 5 for tyres of diagonal construction with normal section heIght;
b) Table 6 for tyres of diagonal construction with low section height.
5.3 Agricultural implement tyres
Tyre size designations, measurement rims, design dimensions of new tyres, and maximum lyre dimensions in service are given Wi
a) Table 8 for tyres of diagonal construction with normal section height;
b) Table 9 for tyres of diagonal construction with low section height.
6 RadIus Index
Radius indices are parameters wtiich are used exclusively for the calculation of forward ground speed during homologation procedures (see for further information ISO 3965).
Values are given in Table 7 for tyres of diagonal and radial constructions with normal section height and for agricultural tractor dnve wheel tyres of diagonal construction with low section height.
They apply to tyl-es inflated to the recommended inflation pressures given in ISO 4251-2 and having a load per lyre corresponding to 50 % of the maximum values at 30 kmlh.
7 Tyre and rim coordination Approved rim contours are given in
a) Table 10 for agricultural drive wheel tractor tyres;
b) Table 11 for agricultural steeling wheel tractor tyres;
C) Table 12 for agricultural implement tyres with normal section height;
d) Table 13 for agflcultursl imement tyres with low section height.
ISO 4251-1 pdf download – Tyres (ply rating marked series) and rimsfor agricultural tractors and machines —Part 1: Tyre designation and dimensions,and approved rim contours
