EXPERTISE & TECHNOLOGIES
This spring steel is of high quality in accordance with DIN EN 10132-4. We exclusively use this spring steel for our original SCHNORR® safety washers and load washers according to DIN 6796.
C67S (1.1231) and C75S (1.1248):
These stainless steel grades (DIN EN 10132-4) are used as cold rolled strip for disc springs of group (DIN EN 16983) up to a thickness of t < 1.25 mm and for our disc springs in the “K” series.
This chromium-vanadium alloyed stainless steel is used in rolled condition (DIN 10132-4 or DIN 10089) for disc springs with a thickness between 1.25 mm to 6 mm. This stainless steel is usually processed in forged form for disk thicknesses of more than 6 mm.
MATERIALS FOR SPECIAL REQUIREMENTS
Corrosion, high temperatures and other aggressive environments require specialized materials. These materials have in general lower tensile strength than standard materials, and should only be specified if absolutely necessary. These springs have a lower overall height than comparable sizes made of standard materials, resulting in lower spring force. This must be taken into consideration when using these materials.
X10 CrNi 18-8 (1.4310):
This chromium-nickel alloyed steel (DIN EN 10151) is the most commonly used material for disc springs up to a thickness of t = 3.0 mm. However, the cold forming process makes it magnetic.
X7 CrNiAl 17-7 (1.4568):
This steel alloy (DIN EN 10151) is a precipitation-hardened spring steel which is processed in cold-strained condition, and it is available in thicknesses up to approx. 2.5 mm. The cold forming process makes this material magnetic.
X5 CrNiMo 17-12-2 (1.4401):
With this steel (DIN EN 10151), the strength is somewhat less than that of the previous two. However, it offers higher corrosion resistance and lower magnetism. Small amounts of this material are hard to procure, and it is thus rarely used.
X22 CrMoV 12-1 (1.4923):
This chromium-molybdenum-vanadium steel (DIN EN 10269) that can be quenched and tempered, has proved very well for the use of heat-resistant disc springs.
X39 CrMo 17-1 (1.4122):
This is a chromium-molybdenum alloyed steel (DIN EN 10088-2) that can be quenched and tempered. This material grade has also proved very well for the use of heat resistant disc springs.
Please note that neither of the mentioned steel grades are considered to be corrosion-resistant steel grades.
ANTI-MAGNETIC AND CORROSION-RESISTANT MATERIALS
CuSn 8 (2.1030):
Tin bronze (DIN EN 1654) is an alloy consisting of copper and tin, maintaining its spring characteristics due to cold forming. Please note that the strength values and the spring forces resulting from it are considerably lower than with the standard material.
CuBe 2 (2.1247):
Copper-beryllium (DIN EN 1654) is an excellent spring material grade which is suitable for extremely low temperatures, down to temperatures close to absolute zero.
These copper alloys are absolutely anti-magnetic, and they have excellent electric conductivity. Furthermore they show a high corrosion resistance.
HEAT-RESISTANT SPECIAL MATERIALS WITH HIGH CORROSION RESISTANCE
The following nickel-based alloys have an excellent resistance against a wide range of conditions. However, they are expensive and often hard to procure. As these material grades are often used under extreme operational conditions, a potential creeping under load might lead to a loss of installation height or loss of force of the disc spring. This creeping will happen as a result from exposure to temperature, time and tension. A disc spring can be used at higher temperatures, for example, when either a low load is chosen or with shorter exposure times. A maximum working temperature can therefore not be determined. The values stated in the material grade overview table can therefore only serve as a guiding value.
NiCr 20 Co 18 Ti (NIMONIC 90) (2.4632):
This nickel-cobalt alloy shows good strength characteristics in high temperatures and can be used for higher temperatures with appropriate dimensioning.
NiCr 15 Fe 7 TiAl (INCONEL X 750) (2.4669) and NiCr 19NbMo (INCONEL 718) (2.4668):
These nickel-chromium alloys are virtually cobalt-free and are often used in nuclear reactor technology.
MATERIALS SYNOPTIC TABLE
For the maximum working temperatures listed, the setting height of the springs depends on the height of the tensions and the time operating in the maximum temperature. Furthermore, the strength diminishes with increasing temperatures to the elasticity module of the material. The operating temperature and thickness ranges are for reference only. With heat-resistant steel grades, heat treatment and hardness deviate from the information given in the mentioned standards.
In case of any queries regarding material grade selection, please contact our engineering department.
A disc spring is a conical shell which can be loaded along its axis either statically or dynamically.
K - SPRINGS
Ball bearings run smoothly and noise-free when pre-loaded with our SCHNORR® “K” disc springs.
Washers refers to a specialty version of a disc spring or washer used to improve security.
Safety washers can be made from different materials and supplied with different surface treatments.