Axle lugs

We usually calculate by hand. If the tower wall is very thick and the whole tower is heavy, we can perform stress analysis and calculation through Ansys software.

Be sure to check. Our company once exported a tower to New Zealand. The welds were not done well and there were some cracks. Fortunately, they did not fall down, otherwise we would have suffered heavy losses. I’ve also seen photos of the tower crane falling halfway when the lifting lugs were not welded securely. I don’t know if it’s dead or not, but the equipment must have been redone. The check is divided into two parts, one is the shaft lug itself, and the other is the local stress. The shaft lug itself can be calculated according to the method provided by the lifting lug standard. For heavy equipment, the tubes of the shaft lugs should not be too thin. Add some ribs inside to increase the moment of inertia. Local stress needs to be checked with emphasis, as there are often problems. To check the stress in all directions from horizontal to vertical during the lifting process, we calculate a value every 5 degrees. You can also use compress to calculate, or compile your own calculation software. The local stress can be improved by adding reinforcement rings and uniformly distributed ribs. There is a picture of a certain comrade in the forum like this. In addition, when calculating, pay attention to the percentage of the total weight supported by the shaft lugs. Some installation plans have the entire equipment suspended in the air. At this time, attention should be paid to the force distribution of the axis and tail cranes. I have always had doubts about this. What I learned is that in some installation plans, the tail crane only pulls, and is basically unforced. In some installation plans, when the tail crane is suspended in the air, the force on the tail crane is very large. I wonder if anyone familiar with it can explain it.