GB/T 45016-2024 Test methods for mechanical automatic tensioner of accessory belt drive system of engine
1 Scope
This document describes the description of tests, test methods, and test reports for the mechanical automatic tensioner of accessory belt drive system of engine (hereinafter referred to as the "tensioner"). The test methods mainly include high-temperature durability test, thermal shock durability test, corrosion test, pollution test, lift test, ozone resistance test, drop test and sharp torsion test.
This document is applicable to the mechanical automatic tensioner for engine applications, but does not apply to tensioner with wheel or bearing, linear tensioner or bidirectional tensioner.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions 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 6931.1 Belt drives - Vocabulary - Part 1: Basic vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 6931.1 and the following apply.
3.1
mechanical automatic tensioner
component that provides tension of a belt by parts such as springs and tensioning arms
3.2
load angle
angle between the resultant force of the drive belt and the tensioning arm when the tensioner of accessory belt drive system of engine is in the nominal working position
3.3
parallelism
maximum parallel error between the bearing mounting surface and the tensioner mounting datum when the tensioning arm is rotated to the nominal working position by applying force to the load angle direction of the tensioning arm
Note: The parallelism is expressed in mm or (°).
3.4
offset
distance between the bearing mounting surface and the tensioner mounting datum when the tensioning arm is rotated to the nominal working position by applying force to the load angle direction of the tensioning arm
3.5
tensioner break-in
preparation step of rotating the tensioning arm for 15min at a temperature of (20±5)℃, a peak-to-peak amplitude of 2° and a frequency of 20Hz before the test to stabilize the damping of the tensioner
3.6
torque
average torque of the tensioner at the nominal working position after break-in
Note: The recorded data includes a complete torque and displacement curve up to 5 cycles of warm-up/break-in.
3.7
damping
pressure or friction force that prevents the tensioning arm of the tensioner from moving in the nominal working position after the tensioner break-in
Note: The recorded data includes a complete torque and displacement curve up to 5 cycles of warm-up/break-in. The damping is expressed in percentage, force, or torque.
4 Description of tests
The tensioner is used in the accessory belt drive system. The tests include high-temperature durability test, thermal shock durability test, corrosion test, pollution test, lift test, ozone resistance test, drop test and sharp torsion test, of which the former four tests can be realized by belt drive or cable drive.
The belt drive test requires that at least one of the driving or driven wheels in the test device is an eccentric wheel, which can make the tensioning arm reach the upper and lower peak values. The drive belt material shall meet the test requirements. The specific device diagram is shown in Figure 1.
Contents
Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions
4 Description of tests
5 Test methods
5.1 High-temperature durability test
5.2 Thermal shock durability test
5.3 Corrosion test
5.4 Pollution test
5.5 Lift test
5.6 Ozone resistance test
5.7 Drop test
5.8 Sharp torsion test
6 Test report
Bibliography
