Perfect fastening of special hardness components for large facilities

The steel and ladle in this project weigh Sa Z000kN, generating a significant overturning moment on the 4.5-meter-long cantilever structure commonly used in China. This massive force is transferred to the base bolts and the foundation, which are arranged in limited diameters or only a few around the circumference. Ensuring the strength and proper tightening of these anchor bolts is crucial for the safe and stable operation of the equipment. As a self-weight static load, the device maintains symmetrical balance and does not produce an overturning moment under normal conditions. However, when the fully filled steel is placed on the cantilever support during production, a transient maximum torque is generated, acting at the center of rotation (Gc). Considering the overload factor and the long-term dynamic load factor, the system must be carefully designed to handle such stresses. One of the most distinctive characteristics of this type of heavy machinery is the large tilting moment caused by the working load. After loading, both tension and compression zones develop within the frame structure. The force plane formed by the anchor bolts and the base can be considered as a column subjected to eccentric loading. The bolt units experience tensile forces, while the base experiences compressive stress. The principle of balancing external torque aligns with the internal force distribution pattern found in beam and column sections. Bolts and foundations designed for a service life exceeding 25 years under normal loads meet the required fatigue strength criteria. Due to space constraints, the application of constraint conditions will be discussed separately. In this paper, we focus on the circumferentially arranged bolt group, derive the combined anti-moment modulus, and calculate the target condition for optimizing the tightening force of the bolts. To avoid excessive tightening that may lead to bolt failure, or insufficient tightening that reduces joint rigidity and causes slack, a practical calculation method for this critical parameter is described separately. For bolts subjected only to tensile loads, we analyze the tensile deformation of the bolt under load and the frame's slack deformation. Using the CLZ method, we calculate the maximum and minimum stresses in the bolt, laying the groundwork for further analysis of fatigue strength and the characteristics of the installation process. The key parameters of the elastic curve in the bolt and frame connection play a vital role in tightening force optimization and ensuring fatigue resistance. This approach is widely applicable to similar equipment that bears large overturning moments. To prevent tipping accidents and ensure long-term reliable operation, in-depth study and discussion on this subject are essential.

Ceiling spotlight

Ceiling Recessed Light,Led Spot Lights Ceiling,Recessed Spot Lights,Spotlight Ceiling Lights

FOSHAN CITY KURUI LIGHTING CO.,LTD , https://www.kuruilighting.com