I am having trouble with the compression spring. According to the calculation formulas such as in JIS, even when the spring is at its solid height, despite 50% of the allowable stress, 10 to 30% of permanent deformation can still occur. I thought it was due to insufficient tempering, but it (SUS304WPB) was tempered at 300℃ for 15 minutes. The temperature in the furnace was fine. In general, in the case of a compression spring such as SUS304WPB φ1.2 and 7N, how much is it allowed to sag even if the calculation guarantees a service life of 10 million times?
Thank you for your inquiry!
In general when estimating the service life of a compression coil spring, the service life when it is at its solid height can not be estimated. With regard to permanent deformation, if the material is stainless steel, it will be difficult to estimate due to the large variation in service life.
If you have a detailed dimensional specification diagram, we will be able to examine it, so if you have any questions, please contact us at the following link! http://www.tokaibane.com/consulting/index.html
Thanks again for your qustion!
* SUS304（EQ to S30400 by ASTM, X5CrNi1810 by DIN, L-No6X5CrNi 18-9 by ISO ）
Thank you for your quick reply, I appreciate it very much.
Specifications are: Material diameter: φ1.2, Coil mean diameter: φ26, Number of active coils: 6.5, Total number of coils: 8.5, Free height: 69mm, Load 1: 2.8N-51mm, Load 2: 7.4N-20mm, Closed-end, SUS304WPB, tempering
In theory, what happens when this spring is stored at its solid height for 3 months? .. I would appreciate it if you could tell me the yield point from calculation. Thank you for your time. (Is there any spring which doesn’t get permanently deformed when stored at its solid height?)
Hello!
Since the current spring has a low stress of 354 N/mm2 when it is at its solid height, it is unlikely to be easily permanently deformed due to stress.
However, at solid height, more stress than required will be generated, so it is highly possible that permanent deformation will occur. (It is not preferable to store at solid height.)
