Overview
ISO 19690-2:2018 - Disc springs - Part 2: Technical specifications defines manufacturing, material, dimensional and performance requirements for disc (Belleville) springs. The standard specifies two quality grades:
- Grade A for basic static applications with low to moderate performance (not for dynamic use).
- Grade B for dynamic applications and high-performance static uses, with tighter manufacturing controls, stricter tolerances and guaranteed fatigue-life data (graphs relating fatigue life to stress).
This part of the ISO 19690 series complements design guidance by setting the technical specification baseline for producers, purchasers and engineers who need consistent, interchangeable disc springs.
Key Topics and Requirements
ISO 19690-2 covers technical matters essential to reliable disc spring performance:
- Materials and heat treatment - acceptable steels and strip materials referenced to ISO/EN/JIS/ASTM delivery standards; Annex C lists representative material grades.
- Manufacturing processes - production quality differences between Grade A and Grade B, including process controls and traceability.
- Permissible stresses - limits for static and dynamic (fatigue) loading; Grade B includes guaranteed fatigue-life graphs as a function of stress.
- Shot peening and surface treatment - requirements for improving fatigue life and corrosion protection (Grade B specifics).
- Presetting, creep and relaxation - procedures and limits to control load loss and dimensional stability over time.
- Dimensions, designation and tolerances - detailed dimensional series, thickness, diameters, free height, coaxiality and allowable load variation.
- Testing and inspection - test methods and acceptance criteria (see informative Annex B).
- Surface condition, hardness and appearance - finish, hardness measurement standards (ISO 6507/6508) and visual requirements.
Practical Applications and Who Uses It
ISO 19690-2 is used where disc springs are critical to mechanical performance:
- Automotive suspensions, clutches and valve-actuation assemblies
- Aerospace landing gear, actuators and vibration isolation
- Industrial presses, bolted joints and preload applications
- Power generation and heavy machinery where fatigue life under cyclic loads is critical
Typical users:
- Spring manufacturers specifying production and QC limits
- Design engineers selecting springs for static or dynamic service
- Purchasing and quality teams ensuring supplier compliance
- Test laboratories validating fatigue life and conformance
Related Standards (if applicable)
ISO 19690-2 references and complements other standards:
Using ISO 19690-2 helps ensure consistent disc spring quality, reliable fatigue performance and interoperability across suppliers and industries.