GB/Z 3480.20-2025Calculation of load capacity of spur and helical gears - Part 20: Calculation of scuffing load capacity - Flash temperature method (English PDF)

Foreword

This document is a standard or guiding technical document.

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents". Drafting.

This document is Part 20 of GB/T (Z)3480 "Calculation of Load Capacity of Spur Gears and Helical Gears". GB/T (Z)3480 has been published.

The following parts were included.

---Part 1: Basic Principles, Overview, and General Influence Coefficients;

---Part 2: Calculation of tooth surface contact strength (pitting);

---Part 3: Calculation of Gear Tooth Bending Strength;

---Part 4: Calculation of Tooth Surface Fracture Bearing Capacity;

---Part 5: Strength and Mass of Materials;

---Part 6: Service life calculation under variable load conditions;

---Part 20: Flash Method for Calculating the Load-Bearing Capacity of Adhesive Bonds;

---Part 21: Calculation of Bonded Load Capacity Using the Accumulated Temperature Method;

---Part 22: Calculation of the bearing capacity of micropitting corrosion;

---Part 31: Example of micropitting load-bearing capacity.

This document adopts ISO /T S6336-20.2022 "Calculation of load-carrying capacity of spur and helical gears - Part 20: Scrap load-carrying capacity". "Force Calculation Flash Temperature Method". The document type has been changed from an ISO technical specification to a national standardization guidance technical document in my country.

The following minimal editorial changes have been made to this document.

---Corrected "epsilonbeta>=1" in Figure 14 to "epsilonbeta>=1.2", the original text was incorrect.

Introduction

GB/T (Z)3480, "Calculation of Load Capacity of Spur Gears and Helical Gears," is widely used in my country's gear industry. These standards constitute... The calculation system for the load-carrying capacity of involute cylindrical gears in my country is helpful for the reliability design of gear products in my country and for fully integrating with international standards. Alignment.

GB/T (Z)3480 describes the calculation method for the load-carrying capacity of involute cylindrical spur gears and helical gears. It is currently proposed to be divided into 11 parts.

The research subjects and calculation methods are different, and the content is related to each other but also independent.

---Part 1: Basic Principles, Overview, and General Influence Coefficients. The purpose is to describe the load-carrying capacity of involute cylindrical spur gears and helical gears.

The basic principles of force calculation are explained, and the values of the general influence coefficient and some correction coefficients are given.

---Part 2: Calculation of Tooth Surface Contact Strength (Pittling). The purpose is to describe the tooth surface contact strength (pitting) based on Hertzian contact theory.

The calculation method for corrosion is given, and the values of some correction coefficients are provided.

---Part 3: Calculation of Tooth Bending Strength. The purpose is to describe a method for calculating the bending strength of gear teeth based on cantilever beam theory, providing... The values of the partial correction coefficients are given.

---Part 4: Calculation of Tooth Surface Fracture Capacity. The purpose is to describe methods developed in recent years for assessing the risk of tooth surface fracture.

---Part 5: Material Strength and Quality. The purpose is to provide technical requirements for different material quality grades and their impact on gear tooth surface contact.

The main factors and allowable values of the ultimate limit of contact strength and the ultimate limit of tooth root bending strength.

---Part 6: Service Calculation under Variable Loading Conditions. The purpose is to describe the service life calculation according to the Palmger-Miner standard under variable loading conditions.

The method for calculating the equivalent value of variable load is based on the rule.

---Part 20: Calculation of Bond Load Capacity using the Flash Temperature Method. The purpose is to describe a method for calculating the maximum contact temperature of meshing tooth surfaces.

The variation of contact temperature along the contact path, and the evaluation of bonding.

---Part 21: Calculation of Adhesive Load-Bearing Capacity using the Accumulated Temperature Method. The purpose is to describe the increase in contact temperature along the contact path of the meshing tooth surfaces.

The calculation method of the weighted average value and the evaluation of adhesive bonding.

---Part 22: Calculation of Micropitting Capacity. The purpose is to describe the minimum oil film thickness of a specific lubricant in the gear contact area.

Calculation methods and evaluation of gear resistance to micropitting.

---Part 30: Application examples of Parts 1, 2, 3, and 5 of GB/T 3480. The purpose is to provide standard users with examples based on... Calculation examples that can be referenced in GB/T 3480.1, GB/T 3480.2, GB/T 3480.3 and GB/T 3480.5 standards.

---Part 31: Micropitting Carrying Capacity Examples. The aim is to provide standard users with a reference based on GB /Z 3480.22. Calculation example.

Table 1 shows the names of the parts of GB/T (Z)3480 and their corresponding ISO standards. Note: Use the parts of GB/T (Z)3480 as specific examples.

When determining acceptance criteria for special designs, the agreement of both the manufacturer and the purchaser is required.

The relationships between the parts of ISO 6336 are as follows. Parts 1 to 19 specify the fatigue resistance measurement for gear load capacity calculation.

The calculation method; Parts 20 to 29 mainly describe the frictional characteristics of tooth surface contact under lubrication conditions; Parts 30 to 39 Calculation examples corresponding to previous standards are provided. As experimental data accumulates, ISO 6336 may be further improved with the addition of new sections.

Damage resistance calculation for gears.

1 Scope

This document describes a method for assessing bonding risk based on the concept of Block contact temperature and provides calculation formulas.

This basic concept applies to all mechanical components with moving contact areas. The flash temperature calculation formula applies to Hertz waves that are strip-shaped or approximately strip-shaped.

Contact area and working conditions characterized by a sufficiently high Péclet number.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are not included.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies. This document.

Note: GB/T 3374.1-2019 Gears - Terminology and Definitions - Part 1: Geometric Definitions (ISO 1122-1:1998, IDT)

ISO 1328-1 Cylindrical gears - ISO tooth surface tolerance classification system - Part 1: Definition and permissible values of tooth surface deviations (Cylindrical)

Note: GB/T 10095.1-2022 Cylindrical gears - ISO tooth surface tolerance classification system - Part 1: Definition and permissible values of tooth surface deviations (ISO 1328-1. 2013, IDT)

ISO 6336-1 Calculation of load-carrying capacity of spur and helical gears - Part 1: Basic principles, overview and general influence coefficients (Calcula- encefactors)

Note: GB/T 3480.1-2019 Calculation of load-carrying capacity of spur and helical gears - Part 1: Basic principles, overview and general influence coefficients (ISO 6336-1. 2006, IDT)

Note: GB/T 3481-1997 Gear Tooth Wear and Damage Terminology (idt ISO 10825:1995)

3 Terms and definitions, symbols and units