Abstract:  BOP is a safety device that controls the pressure in the well. The installed shear ram needs to cut off the work string in an emergency to ensure safe well shut-in. In order to accurately predict the shearing ability of the shearing ram to the drill pipe, according to the working mechanism and process of the ram shearing drill pipe, considering shear ram structure parameters, drill pipe performance and shear conditions, based on the compressive stress formula a model predicting shear force is established. The shearing test results show that the relative deviation between the theoretic and the actual test data is about 10% , which meets the deviation requirements of engineering practice. This study can effectively compensate for the shortcomings of APISpec16A in terms of prediction and evaluation of shearing force of the ram. It can be a reference for structure design of the shear ram.

Key words:  , ram BOP, shearram, shearing force, compressive stress formula 

摘要：  防喷器是控制井内压力的安全设备，其中安装的剪切闸板在紧急情况下需要及时切断作业管柱才能 确保实现安全封井。为了准确预测剪切闸板对钻杆的剪切能力，根据闸板剪切钻杆的工作机理及过程，以压应力公式作为理论基础，综合考虑闸板结构参数、钻杆性能参数及剪切工况参数，建立了闸板剪切力预测模型，并将预 测方法应用于某型号剪切闸板剪切 S135钻杆实例上以验证预测模型的有效性和可靠性。试验结果表明，利用文 章所建立的预测模型计算出的剪切力数值与剪切试验得到的剪切力数据相对偏差在10％左右，满足工程实践的偏 差要求。研究结果可有效弥补 APISpec16A中对于剪切闸板剪切能力预测评估的不足，并为防喷器剪切闸板的剪 切力预测及结构设计提供了一定的理论依据。

关键词:  闸板防喷器, 剪切闸板, 剪切力, 压应力公式