ASTM_F_551_-_F_551M_-_09a.pdf

Designation:F551/F551M09aStandard Practice forUsing a 1.707-m 67.23-in.Diameter Laboratory TestRoadwheel in Testing Tires1This standard is issued under the fixed designation F551/F551M;the number immediately following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the requirements for a 1.707-m67.23-in.diameter laboratory roadwheel for durability andendurance testing of tires under controlled operating andenvironmental conditions.1.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system may not be exact equivalents;therefore,eachsystem shall be used independently of the other.Combiningvalues from the two systems may result in non-conformancewith the standard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.For specificprecautionary statements,see Section 7 and Note 1.2.Referenced Documents2.1 ASTM Standards:2F538 Terminology Relating to the Characteristics and Per-formance of Tires3.Terminology3.1 DefinitionsDefinitions given in Terminology F538 areregarded as standard.4.Summary of Practice4.1 This practice describes the specifications and dimen-sions of a 1.707-m 67.23-in.diameter laboratory roadwheelsystem for testing of one or more tire assemblies undercontrolled conditions.It also describes the calibration proce-dures for the standard operation of the wheel.5.Significance and Use5.1 The 1.707-m 67.23-in.diameter laboratory test road-wheel is one of the most extensively employed testing devicesfor tire durability and endurance testing.5.2 This test apparatus operating in the laboratory at con-trolled surface speeds,loads,and ambient temperatures simu-lates,to a degree,tire-operating conditions resembling actualservice.Because of the roadwheel curvature,the test tire isfatigued more rapidly than a tire operating on a road.5.3 The laboratory roadwheel described in this practice issuitable for comparative evaluation of tires under controlledoperating and environmental conditions.5.4 While the laboratory roadwheel may not reproducestructural fatigue exactly as it occurs in service,the laboratorywheel can be used to produce fatigue under controlled condi-tions.6.Apparatus6.1 Laboratory Test RoadwheelA laboratory test road-wheel consists of a large steel wheel against which one or moretire-wheel assemblies are pressed at specific loads(see Fig.1).6.1.1 The roadwheel shall have an outside diameter of 1.707m 67.23 in.6 0.5%.This dimension originated from thechoice of the circumference of the roadwheel as being1300mile.6.1.2 The width of the roadwheel shall be such that theedges are not in contact with the tire under test.6.1.3 The surface roughness of the roadwheel that is incontact with the tire shall not be in excess of 3.18 m 125 in.and must be continuous and without holes or projections.Where it is necessary to provide for the affixing of special testaccessories such as cleats,the empty bolt holes in the path ofthe tire contact width should be plugged,so as to match thewheel curvature and be within the maximum specified surfaceroughness.6.1.4 The total indicated radial runout of the wheel shall notexceed 0.25 mm 0.01 in.6.2 Loading System:1This practice is under the jurisdiction of ASTM Committee F09 on Tires and isthe direct responsibility of Subcommittee F09.10 on Equipment,Facilities andCalibration.Current edition approved Nov.1,2009.Published December 2009.Originallyapproved in 1977.Last previous edition approved in 2009 as F551 09.DOI:10.1520/F0551_F0551M-09A.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.2.1 The loading system shall be capable of applying andcontrolling the tire loading force to the desired level.6.2.2 The tire loading force shall pass through the axis of thetire under test and the axis of the roadwheel at all times.6.2.3 The axis of rotation of the roadwheel and the axis ofrotation of the tire undergoing test shall be parallel within 10min of arc for camber and slip angle.6.2.4 Each tire-loading system should be equipped with adevice that causes the tire to be retracted from the roadwheelimmediately upon its reaching a preset deflection indicative oftire failure or air loss.6.3 DriveThe drive shall be capable of rotating the road-wheel and maintai