Belleville Fasteners - DIN 6796
Belleville Fasteners DIN 6796 give permanent pressure to the union between a screw and a nut to prevent the loss of pre-load on it; achieveing in this way a static fix regardless of vibrations and other relaxations which might appear with time.
These are only useful to protect from axial loads.
Belleville Fasteners DIN 6796 are made to be static. Their use in dynamic applications is not recommended.
In the following table we can contrast values for the residual elastic force, which can only be used as a reference for users of Fastener Bellevilles. It shows the lowest limit of residual elastic force to hold unions through Belleville Fasteners. These values are only aproximate never to be taken as exact.
Belleville Fasteners DIN 6796 are available in C60 (DIN 17221 and DIN 17222) hardness range between 420 and 510 HV. Made of this material they can have different finishes: Oiled; Phosphating + Oiled; Mechanical Zinc Plating.
Fastener Bellevilles DIN 6796 are also available with other materials: Stainless Steel range: X12 Cr Ni 177 (AISI 301) and X7 Cr Ni Al 17-7 (AISI 631). Most common sizes for DIN 6796 can be supplied in Niquel alloys (NICr 19 NbMo) material known as Inconel 718 to be used where a high resistance to corrosion is required or temperature is excesive for conventional materials. Residual elastic forces for this materials will be slightly lower to the previously shown due to a lower elasticity they have.