[Code of Federal Regulations]
[Title 49, Volume 5]
[Revised as of October 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR571.129]
[Page 412-419]
TITLE 49--TRANSPORTATION
OF TRANSPORTATION
PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS--Table of Contents
Subpart B--Federal Motor Vehicle Safety Standards
Sec. 571.129 Standard No. 129; New non-pneumatic tires for passenger cars.
S1 Scope. This standard specifies tire dimensions and laboratory
test requirements for lateral strength, strength, endurance, and high
speed performance; defines the tire load rating; and specifies labeling
requirements for non-pneumatic spare tires.
S2 Application. This standard applies to new temporary spare non-
pneumatic tires for use on passenger cars.
S3 Definitions.
Carcass means the tire structure except for the tread which provides
the major portion of the tire's capability to deflect in response to the
vertical
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loads and tractive forces that the tire transmits from the roadway to
the non-pneumatic rim, the wheel center member, or the vehicle and which
attaches to the vehicle or attaches, either integrally or separably, to
the wheel center member or non-pneumatic rim.
Carcass separation means the pulling away of the carcass from the
non-pneumatic rim or wheel center member.
Chunking means the breaking away of pieces of the carcass or tread.
Cracking means any parting within the carcass, tread, or any
components that connect the tire to the non-pneumatic rim or wheel
center member and, if the non-pneumatic tire is integral with the non-
pneumatic rim or wheel center member, any parting within the non-
pneumatic rim, or wheel center member.
Load rating means the maximum load a tire is rated to carry.
Maximum tire width means the greater of either the linear distance
between the exterior edges of the carcass or the linear distance between
the exterior edges of the tread, both being measured parallel to the
rolling axis of the tire.
Non-pneumatic rim means a mechanical device which, when a non-
pneumatic tire assembly incorporates a wheel, supports the tire, and
attaches, either integrally or separably, to the wheel center member and
upon which the tire is attached.
Non-pneumatic test rim means with reference to a tire to be tested,
any non-pneumatic rim that is listed as appropriate for use with that
tire in accordance with S4.4.
Non-pneumatic tire means a mechanical device which transmits, either
directly or through a wheel or wheel center member, the vertical load
and tractive forces from the roadway to the vehicle, generates the
tractive forces that provide the directional control of the vehicle and
does not rely on the containment of any gas or fluid for providing those
functions.
Non-pneumatic tire assembly means a non-pneumatic tire, alone or in
combination with a wheel or wheel center member, which can be mounted on
a vehicle.
Non-pneumatic tire identification code means an alphanumeric code
that is assigned by the manufacturer to identify the tire with regard to
its size, application to a specific non-pneumatic rim or wheel center
member or application to a specific vehicle.
Test wheel center member means with reference to a tire to be
tested, any wheel center member that is listed as appropriate for use
with that tire in accordance with S4.4.
Tread means that portion of the tire that comes in contact with the
road.
Tread separation means pulling away of the tread from the carcass.
Wheel means a mechanical device which consists of a non-pneumatic
rim and wheel center member and which, in the case of a non-pneumatic
tire assembly incorporating a wheel, provides the connection between the
tire and the vehicle.
Wheel center member means, in the case of a non-pneumatic tire
assembly incorporating a wheel, a mechanical device which attaches,
either integrally or separably, to the non-pneumatic rim and provides
the connection between the non-pneumatic rim and the vehicle; or in the
case of a non-pneumatic tire assembly not incorporating a wheel, a
mechanical device which attaches, either integrally or separably, to the
non-pneumatic tire and provides the connection between the tire and the
vehicle.
S4 Requirements.
S4.1 Size and Construction. Each tire shall be designed to fit each
non-pneumatic rim or wheel center member specified for its non-pneumatic
tire identification code designation in a listing in accordance with
section S4.4.
S4.2 Performance Requirements
S4.2.1 General. Each tire shall conform to the following:
(a) Its load rating shall be that specified in a submission made by
a manufacturer, pursuant to S4.4(a), or in one of the publications
described in S4.4(b) for its non-pneumatic tire identification code
designation.
(b) It shall incorporate a tread wear indicator that will provide a
visual indication that the tire has worn to a tread depth of \1/16\
inch.
(c) It shall, before being subjected to either the endurance test
procedure specified in S5.4 or the high speed performance procedure
specified in S5.5,
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exhibit no visual evidence of tread or carcass separation, chunking or
cracking.
(d) It shall meet the requirements of S4.2.2.5 and S4.2.2.6 when
tested on a test wheel described in S5.4.2.1 either alone or
simultaneously with up to 5 tires.
S4.2.2 Test Requirements.
S.4.2.2.1 Test Sample. For each test sample use:
(a) One tire for physical dimensions, lateral strength, and strength
in sequence;
(b) A second tire for tire endurance; and
(c) A third tire for high speed performance.
S4.2.2.2 Physical Dimensions. For a non-pneumatic tire assembly in
which the tire is separable from the non-pneumatic rim or wheel center
member, the dimensions, measured in accordance with S5.1, for that
portion of the tire that attaches to that non-pneumatic rim or wheel
center member shall satisfy the dimensional specifications contained in
the submission made by an individual manufacturer, pursuant to S4.4(a),
or in one of the publications described in S4.4(b) for that tire's non-
pneumatic tire identification code designation.
S4.2.2.3 Lateral Strength. There shall be no visual evidence of
tread or carcass separation, cracking or chunking, when a tire is tested
in accordance with S5.2 to a load of:
(a) 1,500 pounds for tires with a load rating less than 880 pounds;
(b) 2,000 pounds for tires with a load rating of 880 pounds or more
but less than 1,400 pounds.
(c) 2,500 pounds for tires with a load rating of 1,400 pounds or
more, using the load rating marked on the tire or tire assembly.
S4.2.2.4 Tire Strength. There shall be no visual evidence of tread
carcass separation, cracking or chunking, when a tire is tested in
accordance with S5.3 to a minimum energy level of:
------------------------------------------------------------------------
Load rating Minimum energy level
------------------------------------------------------------------------
Below 880 pounds...................... 1950 inch pounds.
880 pounds and above.................. 2600 inch pounds.
------------------------------------------------------------------------
S4.2.2.5 Tire Endurance. When the tire has been subjected to the
laboratory endurance test specified in S5.4, using, if applicable, a
non-pneumatic test rim or test wheel center member that undergoes no
permanent deformation, there shall be no visual evidence of tread or
carcass separation, cracking or chunking. In the case of a non-pneumatic
tire assembly in which the non-pneumatic tire is an integral part of the
assembly, the assembly shall undergo no permanent deformation with the
exception of wear of the tread.
S4.2.2.6 High Speed Performance. When the tire has been subjected
to the laboratory high speed performance test specified in S5.5, using
if applicable, a non-pneumatic test rim or test wheel center member that
undergoes no permanent deformation, there shall be no visual evidence of
tread or carcass separation, cracking or chunking. In the case of a non-
pneumatic tire assembly in which the non-pneumatic tire is an integral
part of the assembly, the assembly shall undergo no permanent
deformation with the exception of wear of the tread.
S4.3 Labeling Requirements. Each non-pneumatic tire or, in the case
of a non-pneumatic tire assembly in which the non-pneumatic tire is an
integral part of the assembly, each non-pneumatic tire assembly shall
include, in letters or numerals not less than 0.078 inches high, the
information specified in paragraphs S4.3 (a) through (f). The
information shall be permanently molded, stamped or otherwise
permanently marked into or onto the non-pneumatic tire or non-pneumatic
tire assembly, except that the information specified in S4.3(d) and
S4.3(g) may appear on a label that is permanently attached to the tire
or tire assembly. If a label is used, it shall be subsurface printed,
made of a material that is resistant to fade, heat, moisture, and
abrasion, and attached in such a manner that it cannot be removed
without destroying or defacing the label on the non-pneumatic tire or
tire assembly. The information shall appear on both sides of the non-
pneumatic tire or non-pneumatic tire assembly, except, in the case of a
non-pneumatic tire assembly which has a particular side that must always
face outward when mounted on a vehicle, in which case the information
shown in paragraphs S4.3 (a) through (g) shall only be required on
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the outward facing side. The information shall be positioned on the tire
or tire assembly such that it is not placed on the tread or the
outermost edge of the tire and is not obstructed by any portion of any
non-pneumatic rim or wheel center member designated for use with that
tire in S4.4 of this standard or in 49 CFR 571.110 or 49 CFR 571.120.
(a) The non-pneumatic tire identification code (``NPTIC'');
(b) Load rating, which, if expressed in kilograms, shall be followed
in parenthesis by the equivalent load rating in pounds, rounded to the
nearest whole pound;
(c) For a non-pneumatic tire that is not an integral part of a non-
pneumatic tire assembly, the size and type designation of the non-
pneumatic rim or wheel center member that is contained in the submission
made by a manufacturer, pursuant to S4.4(a), or in one of the
publications described in S4.4(b) for that tire's non-pneumatic tire
identification code designation;
(d) The name of the manufacturer or brand name;
(e) The symbol DOT in the manner specified in part 574 of this
chapter, which shall constitute a certification that the tire conforms
to applicable Federal motor vehicle safety standards;
(f) The tire identification number required by Sec. 574.5 of this
chapter;
(g) The labeling requirements set forth in S6 of Standard No. 110
(Sec. 571.110), or S8 of Standard No. 120 (Sec. 571.120).
S4.4 Non-Pneumatic Tire Identification Code and Non-Pneumatic Rim/
Wheel Center Member Matching Information. For purposes of this standard,
S8 of 49 CFR 571.110 and S10 of 49 CFR 571.120, each manufacturer of a
non-pneumatic tire that is not an integral part of a non-pneumatic tire
assembly shall ensure that it provides a listing to the public for each
non-pneumatic tire that it produces. The listing shall include the non-
pneumatic tire identification code, tire load rating, dimensional
specifications and a diagram of the portion of the tire that attaches to
the non-pneumatic rim or wheel center member, and a list of the non-
pneumatic rims or wheel center members that may be used with that tire.
For each non-pneumatic rim or wheel center member included in such a
listing, the information provided shall include a size and type
designation for the non-pneumatic rim or wheel center member, and
dimensional specifications and a diagram of the non-pneumatic rim or
portion of the wheel center member that attaches to the tire. A listing
compiled in accordance with paragraph (a) of this section need not
include dimensional specifications or a diagram of the non-pneumatic rim
or portion of the wheel center member that attaches to the tire if the
non-pneumatic rim's or portion of the wheel center member's dimensional
specifications and diagram are contained in each listing published in
accordance with paragraph (b) of this section. The listing shall be in
one of the following forms:
(a) Listed by manufacturer name or brand name in a document
furnished to dealers of the manufacturer's tires or, in the case of non-
pneumatic tires supplied only as a temporary spare tire on a vehicle, in
a document furnished to dealers of vehicles equipped with the tires, to
any person upon request, and in duplicate to the Office of Vehicle
Safety Standards, Crash Avoidance Division, National Highway Traffic
Safety Administration, U.S. Department of Transportation, Washington, DC
20590; or
(b) Contained in publications, current at the date of manufacture of
the tire or any later date, of at least one of the following
organizations:
The Tire and Rim Association
The European Tyre and Rim Technical Organization
Japan Automobile Tire Manufacturers' Association, Inc.
Deutche Industrie Norm
British Standards Institute
Scandinavian Tire and Rim Organization
Tyre and Rim Association of Australia
S5. Test Procedures.
S5.1 Physical Dimensions. After conditioning the tire at room
temperature for at least 24 hours, using equipment with minimum
measurement capabilities of one-half the smallest tolerance specified in
the listing contained in the
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submission made by a manufacturer pursuant to S4.4(a), or in one of the
publications described in S4.4(b) for that tire's non-pneumatic tire
identification code designation, measure the portion of the tire that
attaches to the non-pneumatic rim or the wheel center member. For any
inner diameter dimensional specifications, or other dimensional
specifications that are uniform or uniformly spaced around some
circumference of the tire, these measurements shall be taken at least
six points around the tire, or, if specified, at the points specified in
the listing contained in the submission made by an individual
manufacturer, pursuant to S4.4(a), or in one of the publications
described in S4.4(b) for that tire's non-pneumatic tire identification
code designation.
S5.2 Lateral Strength.
S5.2.1 Preparation of the tire.
S5.2.1.1 If applicable, mount a new tire on a non-pneumatic test
rim or test wheel center member.
S5.2.1.2 Mount the tire assembly in a fixture as shown in Figure 1
with the surface of the tire assembly that would face outward when
mounted on a vehicle facing toward the lateral strength test block shown
in Figure 2 and force the lateral strength test block against the tire.
S5.2.2 Test Procedure.
S5.2.2.1 Apply a load through the block to the tire at a rate of 2
inches per minute, with the load arm parallel to the tire assembly at
the time of engagement and the first point of contact with the test
block being the test block centerline shown in Figure 2, at the
following distances, B, in sequence, as shown in Figure 1:
B=A--1 inch
B=A--2 inches
B=A--3 inches
B=A--4 inches
B=A--5 inches, and
B=A--6 inches.
However, if at any time during the conduct of the test, the test block
comes in contact with the non-pneumatic test rim or test wheel center
member, the test shall be suspended and no further testing at smaller
values of the distance B shall be conducted. When tested to the above
procedure, satisfying the requirements of S4.2.2.3 for all values of B
greater than that for which contact between the non-pneumatic test rim
or test wheel center member and the test block is made, shall constitute
compliance to the requirements set forth in S4.2.2.3.
S5.3 Tire Strength.
S5.3.1 Preparation of the Tire.
S5.3.1.1 If applicable, mount the tire on a non-pneumatic test rim
or test wheel center member.
S5.3.1.2 Condition the tire assembly at room temperature for at
least three hours.
S5.3.2 Test Procedures.
S5.3.2.1 Force the test cleat, as defined in S5.3.2.2, with its
length axis (see S5.3.2.2(a)) parallel to the rolling axis of the non-
pneumatic tire assembly, and its height axis (see S5.3.2.2(c)),
coinciding with a radius of the non-pneumatic tire assembly, into the
tread of the tire at five test points equally spaced around the
circumference of the tire. At each test point, the test cleat is forced
into the tire at a rate of two inches per minute until the applicable
minimum energy level, as shown in S4.2.2.4, calculated using the formula
contained in S5.3.2.3, is reached.
S5.3.2.2 The test cleat is made of steel and has the following
dimensions;
(a) Minimum length of one inch greater than the maximum tire width
of the tire,
(b) Width of one-half inch with the surface which contacts the
tire's tread having one-quarter inch radius, and
(c) Minimum height of one inch greater than the difference between
the unloaded radius of the non-pneumatic tire assembly and the maximum
radius of the non-pneumatic rim or wheel center member, if used with the
non-pneumatic tire assembly being tested.
S5.3.2.3 The energy level is calculated by the following formula:
[GRAPHIC] [TIFF OMITTED] TC01AU91.066
where
E=Energy level, inch-pounds;
F=Force, pounds; and
P=Penetration, inches
S5.4 Tire Endurance.
S5.4.1 Preparation of the tire.
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S5.4.1.1 If applicable, mount a new tire on a non-pneumatic test
rim or test wheel center member.
S5.4.1.2 Condition the tire assembly to 1005 deg.F.
for at least three hours.
S5.4.2 Test Procedure.
S5.4.2.1 Mount the tire assembly on a test axle and press it
against a flat-faced steel test wheel 67.23 inches in diameter and at
least as wide as the maximum tire width of the tire to be tested or an
approved equivalent test wheel, with the applicable test load specified
in the table in S5.4.2.3 for the tire's non-pneumatic tire
identification code designation.
S5.4.2.2 During the test, the air surrounding the test area shall
be 1005 deg.F.
S5.4.2.3 Conduct the test at 50 miles per hour (m.p.h.) in
accordance with the following schedule without interruption: The loads
for the following periods are the specified percentage of the load
rating marked on the tire or tire assembly:
Percent
4 hours...............................................................85
86 hours..............................................................90
24 hours.............................................................100
S5.4.2.4 Immediately after running the tire the required time,
allow the tire to cool for one hour, then, if applicable, detach it from
the non-pneumatic test rim or test wheel center member, and inspect it
for the conditions specified in S4.2.2.5.
S5.5 High Speed Endurance.
S5.5.1 After preparing the tire in accordance with S5.4.1, if
applicable, mount the tire assembly in accordance with S5.4.2.1, and
press it against the test wheel with a load of 88 percent of the tire's
load rating as marked on the tire or tire assembly.
S5.5.2 Break in the tire by running it for 2 hours at 50 m.p.h.
S5.5.3 Allow to cool to 1005 deg.F.
S5.5.4 Test at 75 m.p.h. for 30 minutes, 80 m.p.h. for 30 minutes
and 85 m.p.h. for 30 minutes.
S5.5.5 Immediately after running the tire for the required time,
allow the tire to cool for one hour, then, if applicable, detach it from
the non-pneumatic test rim or test wheel center member, and inspect it
for the conditions specified in S4.2.2.6.
S6. Nonconforming tires. Any non-pneumatic tire that is designed
for use on passenger cars that does not conform to all the requirements
of this standard, shall not be sold, offered for sale, introduced or
delivered for introduction into interstate commerce, or imported into
the United States, for any purpose.
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[GRAPHIC] [TIFF OMITTED] TC01AU91.067
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[GRAPHIC] [TIFF OMITTED] TC01AU91.068
[55 FR 29590, July 20, 1990, as amended at 56 FR 19312, Apr. 26, 1991]
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