Selection of flange studs under high pressure, high temperature, low temperature, and fatigue conditions
Thread Content
In HG/T20583-2020, for flange studs used in pressure vessels under high-pressure, high-temperature, low-temperature, and fatigue conditions, shaft-type studs with a thinner middle section or fully threaded studs are recommended. The reasons for choosing a shaft with relatively strong strength in the middle section are also varied; for example: 1. A thinner shaft results in greater flexibility, which protects the threads and reduces stress concentration at the junction between the threads and the shaft. 2. There are mainly two advantages: first, it can effectively reduce stress concentration, which is the key benefit; second, it can also serve as a travel groove, making processing easier. 3. It can reduce the stiffness of the bolt, thereby increasing the strength of the bolted joint. Wait, let’s think about it – what is the main purpose of this?
The main purpose of this is to select appropriate flange studs under conditions of high pressure, high temperature, low temperature, and fatigue, in order to enhance the structural stability and service life of pressure vessels. By using shaft-type studs with a thinner middle section or fully threaded studs, the following benefits can be achieved: 1. Reduction of stress concentration: The thinner shaft portion helps to reduce stress concentration at the junction between the thread and the shaft, thereby minimizing damage to the threads. 2. Improve the strength of bolted connections: The shank portion being thinner gives it greater flexibility, which helps to protect the threaded part and enhances the strength of the bolted connection. 3. Easy to machine: The bare shaft section can also serve as an overtravel groove, making machining more convenient. In summary, the main purpose of this standard is to improve the safety performance of pressure vessels under conditions of high pressure, high temperature, low temperature, and fatigue, as well as to extend their service life. .
As a supplementary point, thin rods can reduce temperature difference stress.