CN201330573Y - Bottom-hole pressure precision control system of under balance drilling - Google Patents

Abstract

The utility model relates to an underbalanced drilling bottomhole pressure precise control system for petroleum drilling, which comprises an underbalanced drilling data acquisition system (5), a choke manifold (6), a CAN_BUS bus system (4), and a casing pressure sensor (8). , the actuator (7) installed on the choke manifold (6), the pulse pressure sensor (3) from the mud line to the inlet end of the standpipe (2), and the bottom hole pressure acquisition unit installed on the drill string near the drill bit (1) Composition, the actuator (7) and the pulse pressure sensor (3) are respectively connected with the CAN_BUS bus system (4) with data lines, and the CAN_BUS bus system (4) is connected with the underbalanced drilling data acquisition system (5) with data lines , using real-time transmission of bottomhole pressure data to the ground, real-time control of equipment can ensure the underbalanced state of the bottomhole, and effectively avoid the error and lag of the model calculation and the actual bottomhole pressure data from affecting the control accuracy of the underpressure value.

Description

Precise Bottomhole Pressure Control System for Underbalanced Drilling

technical field

The utility model relates to an oil and gas field drilling operation tool, in particular to an accurate control system for underbalanced drilling well bottom pressure.

Background technique

In recent years, with the increase of oil and gas reservoir exploration and development workload in low-pressure, low-permeability formations, deep formations and complex areas, due to large investment and long drilling cycle, how to increase oil and gas production and recover drilling costs as soon as possible is the key to the economic exploration of the above-mentioned complex oilfields. The key issues to be considered in development, and the technical advantages of underbalanced drilling, which is beneficial to reservoir protection and can increase drilling speed, have gradually attracted the attention of decision makers in major oilfield companies at home and abroad, benefiting from the above-mentioned market demand and underbalanced drilling. With the continuous development and improvement of the drilling technology itself, there has been an upsurge in the application of underbalanced drilling in China.

In liquid phase underbalanced drilling, the underpressure difference is very important for controlling the bottomhole underbalanced state. The underpressure value refers to the difference between the bottomhole pressure and the bottomhole formation pore pressure. If the underpressure value is too large, the ground equipment It is difficult to control and deal with, and may lead to formation collapse, sand production, and damage to the connectivity of the formation seepage network, resulting in a serious decrease in formation permeability. Therefore, how to accurately control the bottom hole pressure during the underbalanced drilling process to keep the bottom hole pressure within the design range to ensure the safety and reliability of the underbalanced drilling operation is the first problem that the underbalanced technical service personnel should consider.

At present, in the field operation of underbalanced drilling, the combination of theoretical model and field measured wellhead vertical pressure and casing pressure is mostly used, and the bottom hole pressure is calculated by software, and then the ground equipment is controlled (automatically or manually controlled) to adjust the wellhead casing pressure. In this way, the underpressure value at the bottom of the well is controlled within the design range. These methods can control the underpressure value to a certain extent, but due to the influence of multiphase flow pattern diversity, the theoretical calculation is inaccurate, and small changes in some parameters often cause the underbalanced drilling state to disappear, resulting in the actual It has not reached the underbalanced state, which affects the quality and safety of underbalanced drilling operations.

Contents of the invention

The underbalanced drilling bottomhole pressure precise control system provided by the utility model can collect the bottomhole pressure, transmit the bottomhole pressure data to the ground in real time, and use the real-time bottomhole pressure data to compare with the pre-designed pressure value to accurately control the bottomhole pressure. Balance the underpressure value at the bottom of the drilling well to ensure the underbalanced state at the bottom of the well.

In order to achieve the above object, the utility model adopts the following technical solutions: mainly by the underbalanced drilling data acquisition system, choke manifold, CAN_BUS bus (abbreviation of ControllerAreaNetwork-BUS, i.e. controller local area network bus technology) system, casing pressure sensor, executive The bottom hole pressure acquisition unit is installed on the drill string near the drill bit, and the pressure and temperature data collected by it are converted into pulse signals and uploaded to the mud pipeline to the inlet end of the standpipe. The pulse pressure sensor, the pulse pressure sensor transmits the received pulse signal to the CAN_BUS bus system through the data line, the underbalanced drilling data acquisition system has a data line connected to the CAN_BUS bus system, and decodes, analyzes and judges the pulse data, and the control computer sends The actuator installed on the choke manifold issues instructions to control the opening and closing of the hydraulic choke valve. The casing pressure sensor collects the casing pressure value and transmits it to the CAN_BUS bus system through the data line, and then sends it to the underbalanced drilling data acquisition system for analysis. , and then precisely controlled.

The bottom hole pressure acquisition unit involved in the utility model has been disclosed in the patent (utility model name: a bottom hole data acquisition and transmission device, application number: 2008200063778) applied by Karamay Drilling Technology Research Institute of Western Drilling, which belongs to the prior art .

Beneficial effects of the utility model: due to the adoption of real-time transmission of the bottom-hole pressure data to the ground, the surface equipment is controlled in real time to ensure the unbalanced pressure state at the bottom of the well, and the error between the calculation of the multiphase flow model and the actual bottom-hole pressure data is effectively avoided and hysteresis will affect the control accuracy of the undervoltage value.

Description of drawings

Fig. 1 is a structural schematic diagram of the utility model.

specific implementation plan

Below in conjunction with accompanying drawing, the utility model is further described.

The utility model is mainly composed of an underbalanced drilling data acquisition system 5, a choke manifold 6, a CAN_BUS bus system 4, a casing pressure sensor 8, an actuator 7, a pulse pressure sensor 3 and a bottom hole pressure acquisition unit 1. 1 Connected to the drill string near the drill bit, the pressure and temperature data collected by it are transmitted to the ground in a pulsed manner to the pulse pressure sensor 3 installed at the position from the mud pipeline to the inlet end of the standpipe, and the pulse pressure sensor 3 will receive the data through the data line The pulse signal is transmitted to the CAN_BUS bus system 4, and the underbalanced drilling data acquisition system 5 is connected to the CAN_BUS bus system 4 with a data line, and decodes, analyzes and judges the pulse data, and the hydraulic throttle valve installed in the throttle manifold 6 The throttle valve opening sensor in the upper actuator 7 has a data line connected to the CAN_BUS bus system 4, and the control computer sends instructions to the actuator 7 to control the opening and closing of the hydraulic throttle valve, which is installed on the casing pressure gauge The upper casing pressure sensor 8 collects the casing pressure value and transmits it to the CAN_BUS bus system 4 through the data line, and then to the underbalanced drilling data acquisition system 5 for analysis and precise control.

Its working principle is: the bottom hole pressure acquisition unit 1 collects bottom hole pressure and temperature data, and transmits them to the ground in a pulsed manner. The ground pressure sensor 3 receives the pulse signal and transmits it to the underbalanced drilling data acquisition computer 8 through the CAN_BUS bus system 4 for filtering. , identify, decode and restore the pressure data, through the calculation and analysis of the bottomhole pressure processing module in the underbalanced drilling data acquisition system 5, the deviation between the measured bottomhole pressure value and the pre-designed pressure value is obtained, and whether the deviation exceeds the range . If it exceeds the range, the control module of the underbalanced drilling data acquisition system 5 sends a control command to the actuator 7, and the stepping motor in the actuator 7 drives the hydraulic throttle valve to control its opening and closing degree; The opening sensor of device 7 feeds back to the control module whether the opening is in place; the opening and closing degree of the hydraulic throttle valve directly affects the change of wellhead casing pressure, and acts on the bottom of the well to make the bottom well pressure change.

Claims (1)

1. underbalanced drilling well bottom pressure accuracy-control system, mainly by under balance pressure drilling data collecting system (5), choke manifold (6), CAN_BUS bus system (4), cover pressure sensor (8), actuator (7), pulse sensor (3) and the bottom pressure collecting unit (1) that is installed on the drill string are formed, it is characterized in that: shaft bottom collecting unit (1) is installed on the drill string of nearly bit location, the pressure and temp transformation of data of its collection becomes pulse signal to be uploaded to be installed in the pulse sensor (3) of mud line to standpipe arrival end position, pulse sensor (3) transfers to CAN_BUS bus system (4) by data wire with the received pulse signal, under balance pressure drilling data collecting system (5) has data wire to be connected with CAN_BUS bus system (4), the throttle valve opening sensor that is installed in the actuator (7) on the choke manifold (6) has data wire to be connected to CAN_BUS bus system (4), send instruction by the control computer to actuator (7), the choke valve that surges of control choke manifold (6) is opened, close, cover pressure sensor (8) collection casing pressure value transfers to CAN_BUS bus system (4) through data wire and sends under balance pressure drilling data collecting system (5) again to.