Ko'r perchin jumper nimani anglatadi?

Ko'r perchinning sakrash boshi: perchin tirnoq boshini o'ramaganligi sababli, perchinning sakrash boshiga sabab bo'ladi.

https://www.yukerivet.com/news/the-core-of-the-blind-rivet-is-not-completely-pulled-out-what-is-the-reason-for-the-fracture/