Overview
The ISO 7089 flat washer is used in combination with nuts to complete bolts, screws and studs to create secure detachable threaded connections. ISO 7089 is placed under the bolt head to reduce the pressure on the fastener and increase the bearing area of the fastener itself. This prevents surface deformation, increases the attachment area, holds the element to brittle substrate materials and prevents the fastener from loosening.
Fastener group ISO 7089
Depending on the material of manufacture, ISO 7089 divides flat washers into different fastener groups:
- High-strength fasteners
- Brass fastener
- Stainless steel fastener
- Polyamide fasteners
- Copper fasteners
- Aluminum fastener
Materials for the manufacture of washers
Washer material according to ISO 7089:
- Steel
- Brass
- Polyamide
- Copper
- Aluminum
- Stainless steel A2, A4, A5
Where and how ISO 7089 flat washers are used
ISO 7089 is a washer that is required in all structures, no matter what materials the structure is made of: wood, metal or any other. The application of this washer rather depends on the environment in which it will be used.
- Galvanized steel is a good protection against corrosion if the fastener is to be used in an aggressive environment.
- Brass is used if the system is subjected to frequent dynamic, vibration loads.
- Stainless steel allows the fasteners to be used at significant temperature changes and in aggressive and humid environments.
- Polyamide hardware withstands mechanical shocks, does not crack or break at the permissible load factor.
