SAE J332:2020 pdf free
SAE J332:2020 pdf free.Testing Machines for Measuring the Uniformity of Passenger Car and Light Truck Tires
The equipment is essentially an axle or spindle supporting a rim on which tires may be readily mounted, a means for loading the tire against a drum at a specified load and for holding a fixed tire-to-drum center distance during measurements, and a system for measuring the excitation forces equivalent to those at the tire’s spindle as the tire and drum are rotated at prescribed speeds. Rotation can be accomplished by driving either the tire or the drum. There should be provisions for both clockwise and counterclockwise directions of rotation to account for use of tires on left or right sides of the vehicle. The equipment also requires a means for rapid inflation and deflation of the tire, and for control of inflation pressure during rotation.
The supporting structure and components of the machine must be sufficiently rigid to insure that natural frequencies of the machine assemblies (which may be ultimately detected in the measurement of forces) are above 40 times the wheel rotational frequency used in the measurement. For special types of instrumentation that are matched to machine resonances, this requirement may be waived. The drum and wheel spindles are to be rigidly supported with no lash in radial, axial, or tractive directions.
The structure and rims are to accept tires of 559 to 914 mm (22 to 36 in) in diameter and 127 to 330 mm (5 to 13 in) in section width. The equipment is to be capable of rotating tires at a speed in the range of 15 to 60 rpm during the measuring operation and with the option of 300 to 400 rpm for stabilization before measurement.The design should be based on a maximum force between tire and drum of 8.9 kN (2000 Ib) in the radial direction, 2.22 kN (500 Ib) laterally, and 2.22 kN (500 lb) in the tractive direction.SAE J332 pdf free download.
