Hi everyone! Have a good day. I have some problem in calculate nut strength endurance. It's very easy to calculate standard nut because there're so many article and handbook analysis this (as below) For example in Nut M6 (metric) with 6 thread, You can see, stress concentrate at first engaged root is 33.7%. However, now I have to calculate for tapped thread hole with non-standard thread length (number of thread is 14), so, how many percent of load at first root? anybody know calculation formula or an other experiment analysis? Please share this! thanks you so much!
How accurate do you need it to be? The chart's always going to give you an approximation anyway. As the thread length increases, the effect is less and less. And once you've passed 6 or so threads, the effect is relatively minimal. As you can see, the drop off at the first thread from 6 to 10 threads (almost double as many) is only 0.6%. The drop off from 10 to 14 will be something less than that. As a point of reference, nuts are typically designed to fail after the fasteners they are used with, and typically only have 4 threads or so.