Heavy Belleville washer also known as
SCHNORR® HDS Load Washer
These washers conform to DIN6796 and are designed for high demands on the protection of bolt joints.
They have been specially developed for high-strength bolts of Classes 8.8 to 12.9.
This represents the most powerful form of safety washer in the form of a disc spring. The load of the washers have been matched to these bolts and are 70 to 90% of the bolt load in the flat state.
As a highly progressive load increase occurs at the end of the spring deflection when the load washer is flattened the load has been indicated as double the calculated value.