8.3.1 solid control equipment (Figure 8.12 to Figure 8.14; Table 8.1)
Figure 8.12 F-16HL mud pump
Figure 8.13 Solid control system (vibrating screen, desander and desander) of DERRICK Company of America
Figure 8.14 Centrifuge
Table 8.1FL-16HL mud pump's technical parameters
8.3.2 Solid content control design < The drilling fluid vibrating screen can be transformed into double or triple according to the actual demand. At the same time, the equipment can also be used as an underflow vibrating screen of mud cleaner. The drilling fluid vibrating screen has the advantages of high vibration intensity, large screening area, adjustable screen box angle, compact structure, excellent performance and high cost performance. As shown in figure 8.15.
figure 8.15 drilling fluid shaker
the parameters of this drilling fluid shaker are shown in table 8.2.
table 8.2 technical parameters of drilling fluid vibrating screen
GNZS series linear vibrating screen is widely used in oil drilling, metallurgy, building materials, chemical industry, fire resistance, cement, ceramics, grain, food and other industries, and is used for grading various materials to varying degrees. It can be used in assembly line operation to realize automation.
Compared with other types of vibrating screens, GNZS series linear vibrating screens have the following characteristics:
1) Small size, light weight, simple structure, convenient installation and easy maintenance.
2) Low noise, low energy consumption, high efficiency and low cost.
3) high screening accuracy, no dust pollution, which is beneficial to environmental protection.
4) various vibrating screen screens can be replaced, and the service life is long.
(2) drilling fluid desander
ZQJ series cyclone desander is a second-and third-level solid control equipment for treating drilling fluid, which can be divided into desander and desander according to the different diameters of cyclones. Generally, the cyclone combination below 6 inches is called a desliming device, which is a three-stage solid control equipment in drilling operation. The commonly used cyclones are 5 inches and 4 inches, which are mainly used to separate solid particles with particle size of 15 ~ 47 μ m in drilling fluid. According to the required treatment capacity, several groups of cyclones are selected to form a desilter. The cyclone desliming device controlled by Guanneng is widely used in oil drilling and horizontal directional drilling. As shown in figure 8.16.
the parameters of the cyclone desander are shown in table 8.3.
The drilling fluid desander consists of a liquid inlet pipe, a sand discharging cone bucket and a sand discharging port. In the sand discharging cone bucket, there is a rotating component, and the cylinder wall of the rotating component is provided with a separation window. The upper cylinder wall of the rotating component, a group of conical grooves and the liquid inlet pipe constitute a drilling fluid ascending component. The blades of the desander are arranged at the inner bottom of the rotating component, and the sand discharging regulator controls the sand discharging amount. The drilling fluid enters the rotating component from the liquid inlet pipe and is centrifugally rotated by the blades. When the liquid rises to the separation window, the sand particles are separated from the drilling fluid, and the sand particles are discharged into the sand discharge cone bucket through the separation window. The separated drilling fluid enters the rising component, and the drilling fluid enters the drilling fluid tank from the discharge port of the conical groove. The sand particles in the sand discharging cone bucket are discharged through the sand discharging port controlled by the sand discharging regulator.
fig. 8.16 cyclone desander
table 8.3 technical parameters of cyclone desander
(3) drilling fluid desander
cyclone desander is a second-and third-stage solid control equipment for treating drilling fluid, which can be divided into desander and desander according to the different diameters of cyclones. Generally, the cyclone combination below 6 inches is called a desliming device, which is a three-stage solid control equipment in drilling operation. The commonly used cyclones are 5 inches and 4 inches, which are mainly used to separate solid particles with particle size of 15 ~ 47 μ m in drilling fluid. According to the processing capacity required by customers, several groups of cyclones are selected to form a desilter. The cyclone desliming device controlled by Guanneng is widely used in oil drilling and horizontal directional drilling. As shown in figure 8.17.
the parameter table of the cyclone desilter is shown in 8.4.
drilling fluid desilter, with high separation capacity and wide separation particle size range; The underflow of the cyclone is umbrella-shaped with pressure to discharge sand, so that the particles in the separation zone can be discharged quickly, which reduces the probability of blockage of the underflow. The advanced small two-screen shale shaker has the advantages of large handling capacity, low noise and long screen life; The symmetrical liquid inlet mechanism makes the swirl distribution reasonable and the work stable.
(4) Decanting Centrifuge
LW series drilling fluid horizontal spiral discharging and settling centrifuge (Decanting centrifuge) is a special equipment for solid-liquid separation designed according to the characteristics of petroleum drilling fluid, which can complete various procedures such as feeding, centrifugal settling and discharging at full speed, and is mainly used for recovering barite, removing fine solids, reducing the solid content of drilling fluid, controlling the density and viscosity of drilling fluid, ensuring the performance of drilling fluid, and improving the speed. Horizontal spiral discharge settling centrifuge for drilling fluid uses centrifugal settling principle to separate drilling suspension. The suspension enters the drum from the feed pipe through the liquid outlet hole in the screw pusher. Under the centrifugal force, solid particles are pushed to the inner wall of the drum, pushed to the slag outlet at the small end of the drum through the blades on the screw pusher, and the liquid phase overflows through the overflow hole at the big end of the drum. So as to achieve the purpose of continuous separation. Sedimentation centrifuge belongs to the category of horizontal spiral centrifuge, which is called horizontal spiral sedimentation centrifuge. As shown in figure 8.18.
figure 8.17 cyclone desander
table 8.4 parameters of cyclone desander
decanting centrifuge parameters are shown in table 8.5.
LW series oil field centrifuges are composed of three parts: main engine, liquid supply system and control system. When large-capacity centrifuges are used together with high-speed centrifuges, the three-screen and two-machine solid control system scheme can be realized, thus simplifying the solid control system, reducing power consumption and improving purification efficiency. The horizontal spiral centrifuge has incomparable advantages over other centrifuges:
1) It has great adaptability to materials, and the particle size range of solid phase that can be separated is .5～2mm, and it can be separated as usual when the particle size of solid phase is uneven.
fig. 8.18 decanting centrifuge
table 8.5 decanting centrifuge related parameters
2) It can operate automatically, continuously and for a long time, with convenient maintenance, and can be closed.
3) Single machine has large production capacity, compact structure, small floor space and low operating cost.
4) remote automatic control can be realized.
8.3.3 analysis of volume deformation of drilling cuttings
8.3.3.1 analysis of downhole state
at 1m underground, it is mainly magmatic rocks, and at 5m, it is sedimentary rocks. Deep magmatic rocks mainly include granite, diorite, gabbro and peridotite. Deep sedimentary rocks include sandstone, limestone, dolomite and limestone.
According to Heim hypothesis, the initial vertical stress in the depth of rock mass is directly proportional to the gravity of overlying rock mass, while the horizontal stress is roughly equal to the vertical stress. However, for 5m and 1m belong to the deep part, the calculation of in-situ stress should follow the Heim hypothesis.
without considering the tectonic stress of the stratum, only the gravity stress is considered (the rock density is 2.6g/cm3 (2.5 ~ 2.8g/cm3) and the drilling fluid density is 1.3g/cm3). The rock stress is:
Report on the special achievements of the pre-study of the scientific ultra-deep well drilling technology scheme (middle volume)
The drilling fluid stress is:
Pre-study of the scientific ultra-deep well drilling technology scheme.
Report on the Special Achievements of the Pre-study of Scientific Ultra-deep Drilling Technical Scheme (Volume I)
8.3.3.2 Influence of Temperature and Pressure on Rock Elastic Modulus
(1) Influence of Gravity Stress and High Surrounding Rock Pressure on Rock Elastic Modulus
1) Rock Compressive Strength: Triaxial Isobaric Strength >: Triaxial unequal compressive strength >: Uniaxial compressive strength, so the compressive strength of rocks in deep strata is much larger than that in uniaxial case.
2) Deformation of rock: deformation under triaxial isostatic pressing
Therefore, under the condition of triaxial high stress, the compressive strength is much larger and the deformation is smaller. Therefore, under triaxial high stress, the elastic modulus can be 2-3 times that under uniaxial compression, as shown in Figure 8.19.
figure 8.19 stress and strain of sandstone under different surrounding rocks
(2) influence of temperature on elastic modulus (figure 8.2, figure 8.21)
figure 8.2 influence of temperature on elastic modulus of sandstone and limestone
figure 8.21 influence of temperature on elastic modulus of granite
Therefore, the elastic modulus at 3 can be slightly 8% of that under normal conditions.
8.3.3.3 Calculation of cuttings deformation
(1) Select elastic modulus of rock, as shown in Table 8.6.
table 8.6 elastic modulus of some rocks
therefore, the elastic modulus of rough magmatic rocks can be 8GPa, and that of sedimentary rocks can be 4GPa.
(2) determine the linear elastic coefficient of rock, as shown in table 8.7.
linear expansion coefficient of some rocks in Table 8.7
Therefore, the general linear expansion coefficient of rocks can be 2×1-6/℃.
(3) Calculation of volume deformation
Deformation includes deformation caused by stress change and deformation caused by temperature change. Stress and deformation can be divided into two parts, the first part is the volume deformation after rock drilling, and the second part is the volume deformation caused by stress change in the process of cuttings floating.
The first part:
Report on the special research results of scientific ultra-deep well drilling technology scheme (middle volume)
The second part, whether it is 1m or 5m underground, the pressure changes during the floating process are 13MPa and 65MPa respectively. Therefore, the overall volume deformation in this process is the same as that in the first part, which is the calculation of .3%
temperature deformation. Assuming that the drilling fluid reaches the surface at a temperature of 7, and the volume expansion coefficient caused by the temperature is taken as 3 times, then
Report on the special research results of scientific ultra-deep well drilling technology scheme (Volume I)