高压球形封头强度设计

Design of high-pressure spherical head

高压球形封头在内压力作用下处于三向应力状态 ,在弹性失效准则下按不同的强度理论可得到相应的强度计算公式。通过对 4种强度理论及中径公式的分析比较和实例验证 ,表明按中径公式设计的高压球形封头在进行水压试验时其内壁的应力有时会超过材料的屈服极限 ,使球壳出现屈服现象。提出了按中径公式设计高压球形封头不出现屈服现象的条件为 :对高合金钢pc≤0 2 6 2 [σ]tφ ,对碳钢和低合金钢pc≤ 0 347[σ]tφ。

A triaxial stress state exists in the high pressure spherical head under internal pressure The thickness calculation formulas are derived according to different elastic failure criterion By comparing the stress theories with middle radius formula and practical,it shows that the stresses in the internal wall of high pressure spherical head according middle radius formula will exceed the yield stress when it is tested hydraulically Therefore,the conditions for the high pressure spherical head designed according to middle radius formulas without yielding phenomena are p c≤0 262[ σ] tφ for high alloyed steel and p c≤0 347[ σ] tφ for the carbon steel and low alloyed steel