Stresses in Power Screws: Analysis of Torsion, Compression, and Thread Stresses скачать в хорошем качестве

Stresses in Power Screws: Analysis of Torsion, Compression, and Thread Stresses

Stresses in Power Screws Stresses in the body of power screw A1. Shear Stress due to torsion A2. Compression stress due to the load Stresses in Threads B1. Bending stress at the root of thread B2. Shear stress in the middle of thread cross section B3. Bearing stress in threads Power screw thread is in compression, causing elastic shortening of screw thread pitch. Engaging nut is in tension, causing elastic lengthening of the nut thread pitch. Consequently, the engaged threads cannot share the load equally. Experiments indicate the first thread carries 38% of the load, the second thread 25%, and the third thread 18%. The seventh thread is free of load. To find the largest stress in the first thread of a screw-nut combination, use 0.38 F in place of F, and set nt = 1.