Formation sampling while drilling (FSWD) technology has become a research hotspot in oilfield development at home and abroad. The technology is characterized by a comparatively short operation time. Since the operation time is short, the obtained formation data are closer to the real situation in the reservoir. After the formation fluid enters the sample chamber from the sampling module, sealed, and returns from the downhole to the surface, the change in ambient temperature and pressure causes the sample volume to shrink and the sample pressure to decrease correspondingly. The change in temperature and pressure leads to irreversible phenomena such as phase transformation or degassing, which can affect the quality analysis of the sample. To avoid the phenomenon, the pressure in the sample chamber is maintained above the bubble point pressure by pre-charging nitrogen on the ground and boosting adjustment in the downhole, so that the formation sample fluid is consistent with the phase state in the original formation when it is retrieved from the ground. The described method is used to provide results close to the real parameters in the reservoir. As the pre-charged nitrogen and the final sample occupy different cavities of the same vessel, and the volume of the vessel is constant, the change in the parameters, including the sampling volume, temperature difference, and pressure difference between the ground and the well bottom, will cause a change in the pressure of the pre-charged nitrogen. Therefore, the problem of ensuring sample fidelity has become the key to sampling technology. To solve the problem, the method of combining ground pre-charged nitrogen pressure with downhole sample chamber pressurization has been introduced.

随钻地层采样（FSWD）技术已成为国内外油田开发的研究热点。该技术的特点是操作时间相对较短。由于作业时间短，获得的地层数据更接近油藏实际情况。地层流体从采样模块进入采样室，密封，从井下返回地面后，环境温度和压力的变化导致采样体积缩小，采样压力相应降低。温度和压力的变化会导致相变或脱气等不可逆现象，从而影响样品的质量分析。为了避免这种现象，通过在地面预充氮气并在井下进行增压调节，使样品室中的压力保持在泡点压力以上，使地层样品流体从地层中取回时与原始地层中的相态一致​​。地面。所描述的方法用于提供接近储层中真实参数的结果。由于预充氮气和最终样品占据同一容器的不同腔室，且容器体积不变，因此采样体积、温度差、地井压差等参数发生变化底部，会引起预充氮气的压力变化。因此，保证样本保真度的问题成为采样技术的关键。为了解决问题，