论文部分内容阅读
在高温高压环境下的钻井与完井 ,既困难 ,危险性又大。文中阐述了地温梯度、入口钻井液温度、钻井液类型等因素对当量静态钻井液密度的影响 ;建立了高温高压井中当量静态钻井液密度的计算模型 ;分析了钻井液密度变化对井底静压、动压、当量钻井液循环密度和动态波动压力的影响。结果表明 ,利用地面测量的钻井液密度计算井下压力 ,只适用于浅井和中深井 ;对于安全密度窗口很窄的高温高压井 ,必须考虑井筒温度和压力变化对钻井液密度及井内压力系统的影响 ,才能确保高温高压井的施工安全。
Drilling and completion under high temperature and high pressure are both difficult and dangerous. The effects of geothermal gradient, temperature of inlet drilling fluid and type of drilling fluid on equivalent static drilling fluid density are discussed. The calculation model of equivalent static drilling fluid density in high temperature and high pressure well is established. The influence of drilling fluid density on bottom hole static pressure , Dynamic pressure, equivalent drilling fluid circulation density and dynamic fluctuating pressure. The results show that the downhole pressure calculated by measured drilling fluid density is only applicable to shallow wells and medium-deep wells. For high-temperature and high-pressure wells with very tight density windows, the influence of wellbore temperature and pressure on drilling fluid density and well pressure system must be considered , In order to ensure the construction of high temperature and pressure wells safety.