Rims series for tractors, agricultural and forestry machines
1 Scope
This standard specifies the terms, marking, loads, diameters, circumference, rim dimensions and valve holes, rim knurling on bead seats for rims for tractors, agricultural and forestry machines.
This standard is applicable to rims for tractors, agricultural and forestry machines.
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 of the referenced document (including any amendments) applies.
GB/T 9769 Rim contour inspection
3 Terms of rim contour
See Figure 1 for terms of rim contour. See Figure 2 for the part of the tyre shaped to fit the rim.
A——specified rim width; R1——flange compound radius;
B——flange width; R2——flange radius;
C——location and dimension of flange radius; R3——bead seat radius;
D——specified rim diameter; R4——well top radius;
F1, F2——location and dimension of the valve hole in the rim; R5——well bottom radius;
G——flange height; R6——flange edge radius;
H——well bottom depth; R7——radius on the well side;
DF——diameter of bead seat crest; V——dimension of valve hole or slot;
L——well bottom width; α——well bottom angle;
M——location and dimension of the well; β——bead seat angle.
P——bead seat width;
Notes
1 Dimensions marked with * are related to the mounting and dismounting of tyre on the rim, and they are the minimum dimensions of the well, and M represents the limiting position dimension of the well bottom.
2 The well top radius, R4, and the well bottom angle, α, are important parameters for mounting and dismounting tyre on the rim.
3 Mounting side, that is, the tyre will be mounted into or removed from the rim from this side. For a multi-piece rim, the mounting side is on the side from which the flange can be dismounted.
Figure 1 Rim contour
Part of the rim contour curve to ensure tyre shaped correctly to fit the rim Part of the rim contour curve to ensure smooth disassembly and assembly of the tyre
Figure 2 Part of the tyre shaped to fit the rim
4 Marking
The rim specification name is expressed by "Nominal rim diameter ×/-Nominal rim width Rim contour", or "Nominal rim width Rim contour ×/-Nominal rim diameter". Examples are shown in Table 1.
Table 1 Examples of rim specification names
Rim markinga Rim contour Nominal diameter code Characteristic description
Width code Contour code
4?J×15 Or 15×4?J 4? J 15 Asymmetric drop-center
4?J×15-S Or 15×4?J-S 4? J 15 Symmetrical drop-center (-S)
4?J×15H2-S Or 15×4?J H2-S 4? J 15 Symmetrical drop-center (-S), double hump (H2)
18×13 13 18
10.50I-12 Or 12-10.50I 10.50 I 12
a "X" indicates a one-piece rim; "-" indicates a multi-piece rim.
5 Loads
The loads and air pressure applied to the rim/wheel shall not exceed the maximum recommended by the rim/wheel manufacturer. This value may be engraved on the rim/wheel; when the rim/wheel is not marked with such value or the recommended value is exceeded under the service conditions, the rim/wheel manufacturer shall be consulted to ensure that the rim/wheel will not be damaged under the intended service conditions.
6 Rim diameter and circumference
Foreword i
1 Scope
2 Normative references
3 Terms of rim contour
4 Marking
5 Loads
6 Rim diameter and circumference
6.1 Rim diameter
6.2 Rim circumference
7 Rim dimensions and valve holes
7.1 Drop-center (DC) W and DW rims
7.2 Drop-center (DC) DH rims
7.3 Drop-center (DC) C, D, E and F rims
7.4 Drop-center (DC) J, K and KB rims
7.5 Drop-center (DC) LB, 7.00, 9.00, 9, 11, 12, 13 and 14 rims
7.6 5° drop-center (DC) I-55, I-70, I-90 rims and 5° divided (DT) I-55, I-70, I-90 rims
7.7 Divided (DT) C, D, E and F rims
7.8 5° full tapered bead seat rims (TB) with nominal diameter codes 21, 24 and 25
7.9 5° semi-drop-center rims (SDC) with nominal diameter codes 20, 24 and 32
7.10 5° drop-center (DC) A rims and divided (DT) rims for horticultural tyres
7.11 Rims for agricultural tyres with high trafficability - flat base (FB) HF rims
7.12 AT rims for all-terrain vehicle tyres
8 Rim knurling on bead seats
9 Measurement of rim dimensions
