2results about How to "The result error is small" patented technology

The application discloses a kind of welded structure harmonic response structural stress fatigue life prediction method, comprising the following steps: step 1: build the finite element model of welded structure containing weld;Step 2: using unit external load to the finite element model of welded structure harmonic sweep frequency obtains node response displacement;Step 3: according to external load coefficient obtains the unit stiffness matrix and node displacement under external load, as follows: step 4: calculate the simple harmonic response structural stress and equivalent structural stress of structure.The welded structure harmonic response structural stress fatigue life prediction method of the application: (1) compared with traditional quasi-static method, can solve the problem that quasi-static method cannot be carried out vibration fatigue evaluation, (2) compared with frequency domain structural stress method, can solve the problem that frequency domain structural stress method cannot evaluate simple harmonic vibration fatigue, (3) compared with traditional transient structural stress method, the method of the application is more efficient, and the result error is very small.

The utility model discloses an automobile tire pattern depth gauge which comprises a holder and a measuring ruler strip which is vertically and movably inserted in the vertical central axis position of the holder, and ear handles are further arranged on the two sides of the holder. A buckle is horizontally and slidably connected to the position, close to the bottom, of the holder, and a clamping groove corresponding to the buckle in position is formed in the side face of the measuring ruler strip. An annular supporting base is horizontally arranged at the bottom of the holder, and the circle center corresponding to the supporting base is located on the vertical axis of the measuring ruler strip. According to the utility model, the bottom of the holder is coaxially provided with the annular supporting base which is located on the same horizontal plane with the bottom of the holder, so that the depth gauge has a three-dimensional structure, the supporting base can vertically support on the tread of a tire at 360 degrees, and the scale marks on the measuring ruler strip can directly face a worker on the side surface of an automobile; not only can the perpendicularity be easily kept, but also the reading is convenient, the result error caused by reading and operation is greatly reduced, and convenience is brought to use.