升压速率对正拱普通型爆破片爆破压力的影响规律及机理研究

爆破片在设定的爆破压力下迅速动作、及时泄放压力是确保承压设备能够安全运行的关键。影响爆破压力大小的因素很多，其中介质的升压速率直接影响爆破压力的精确度。在0～300 MPa/s范围内测试了升压速率对正拱普通型爆破片爆破压力的影响，发现在较低的升压速率范围内，随着升压速率的提高，爆破压力首先发生一定程度的振荡(有的逐渐降低，有的先升高再降低)，当升压速率继续升高达到某个范围(拐点)时，又逐渐呈上升状态，上升到某个数值后，趋于稳定。基于试验结果，建立爆破片升压速率与应变速率的关系，提出考虑升压速率影响的爆破压力工程估算方法；对不同应变速率的拉伸试样及爆破片进行金相分析和断口形貌分析，揭示不同升压速率下的材料行为对爆破压力的影响机理：低升压速率情况下，升压速率对材料延伸率及应变硬化的影响是爆破压力波动的主要原因；高升压速率下抗拉强度的改变、动载冲击及应力波是爆破压力提高的主要原因。

Study on Effect and Mechanism of Pressure Rise Rate on the Bursting Pressure of Conventional Domed Bursting Disc

As a widely used safety relief device for pressure equipment, it is very important that the bursting disc device can burst accurately under the set pressure. There are many factors affecting the burst pressure, among which the pressure rise rate(PRR) of medium directly affects the accuracy of burst pressure. The manufacturing of conventional simple domed bursting disc with 316L austenitic stainless steel and the bursting test under different PRRs are carried out. The effect of the PRR on the bursting pressure cannot be ignored. When the PRR is low, with the PRR increasing, the bursting pressure will oscillate to some extent(some gradually decreases, and some first increases and then decreases). When the PRR continues to increase and reaches a certain range(inflection point). it gradually rises again to a certain value and tends to be stable. Based on the results, the relationship curve between the PRR and the strain rate is obtained by experimental data. Taking the strain rate as link, the relationship between the PRR and the bursting pressure is established and an engineering estimation formula for the bursting pressure considering PRR is proposed for the first time.Metallographic structure and fracture morphology analysis are carried out for bursting discs with different strain rates, revealing the effect of material behavior on the bursting pressure at different PRRs. From the present study, under low PRRs, the effect of the PRR on the material elongation and strain hardening is dominant factor in fluctuated bursting pressure, while change of tensile strength, dynamic loading impact and stress wave at high PRRs are the dominant factors in increased bursting pressure.