Interpretation of mud invasion terms

The terms of mud low invasion are defined as follows:

1. Low mud invasion is a petroleum engineering term, which refers to the phenomenon that solid particles in drilling fluid enter the formation during drilling, resulting in poor drilling fluid performance and reduced formation permeability. This phenomenon will lead to problems such as lower drilling efficiency, lower oil and gas production and higher production cost.

2. The formation of low mud invasion is related to the solid content of drilling fluid, drilling fluid density, formation pore pressure gradient and other factors. When the pore pressure gradient of formation is quite different from the density of drilling fluid, the solid particles in drilling fluid will enter the formation under the action of pressure difference, which will lead to the decrease of formation permeability. In addition, factors such as viscosity and shear force of drilling fluid will also affect the low invasion degree of mud.

3. In order to reduce the influence of low mud invasion, petroleum engineers have taken a series of measures, such as controlling the solid content of drilling fluid, adjusting the density of drilling fluid and optimizing the rheology of drilling fluid. In addition, low-invasion drilling techniques, such as underbalanced drilling and foam drilling, can be used to reduce the damage of drilling fluid to the formation.

4. Low mud invasion not only affects the efficiency and quality of drilling engineering, but also has a negative impact on the development of oil and gas resources. Therefore, petroleum engineers need to fully understand the formation mechanism and influencing factors of low mud invasion, and take effective measures to reduce its impact to ensure the smooth development and production of oil and gas resources.

The benefits of keeping mud low invasion are as follows:

1. Reduce formation damage: Low mud invasion refers to the phenomenon that solid particles in drilling fluid enter the formation, resulting in the decrease of formation permeability. By keeping mud low invasion, the erosion and erosion of drilling fluid to the formation can be reduced, thus reducing formation damage and protecting oil and gas resources.

2. Improve drilling efficiency: keeping mud low invasion can reduce resistance and friction during drilling, improve cutting efficiency and drilling efficiency of drill bit, shorten drilling cycle and reduce drilling cost.

3. Reduce the risk of lost circulation: lost circulation is a common problem in drilling engineering, and improper handling will lead to drilling failure. Keeping the mud low invasion can reduce the risk of lost circulation, because the solid particles in the mud can form a dense filter cake on the formation surface to prevent liquid leakage.

4. Improve oil and gas recovery: keeping mud low invasion can reduce the pollution and damage to the formation and maintain the original permeability and conductivity of the formation, thus improving oil and gas recovery and increasing oil and gas production and economic benefits.