Siemens PLC equipment in oil drilling applications
Introduction
The project using the SIMATIC control systems used in ZJ30DB, ZJ50DB variable frequency electric drill rig. Our company consisting of the grounds of four joint venture companies. Science and technology as the leading company mainly producing oil drilling equipment and auxiliary equipment, electrical control systems, engineering, environmental protection projects. Selected Siemens SIMATIC 300 series CPU as the control variable frequency electric drill core, PLC and inverter communication using Profibus bus. Due to the high reliability, and field operations on the complexity of the maintenance requirements to bring the system with redundant backup and remote monitoring capabilities. Equipment package appearance shown in Figure 1.
2, the system introduced
The drilling equipment layout is divided into five regions: drilling platform areas, pumping stations, area, power and electric transmission areas, solid control area, tank farm. Drill Taiwan area furnished with winches, rotary table, top drive, driller room, driller concubine and so on, as a dangerous operation area, the entire region require explosion-proof electrical. Mud pump area furnished with group electrical infusion systems and fluid manifold; power and electric transmission zones arranged a diesel generator room, gas purification device housing the source, auxiliary generator room and electric control room; solid arrangement with mud circulation-controlled areas tank, mud tank cleaning equipment and sets; tank areas, including tanks, pumps, pipelines. As the rig floor area as a dangerous explosion-proof areas, in accordance with international and national standards, other regions of the distance of the length of the borehole at least 50 meters. Complete PLC control systems are arranged in electrical control room and driller room, in which electric control room, including two mutually redundant CPU and a set of ET200M, driller room contains a set of ET200M. Electric control room furnished with: PLC control cabinet, power cabinets, rectifier cabinet, VFD cabinets and MCC cabinets. Mechanical and electrical drilling rig driller room sets, gas, hydraulic control in one, apart from the control cabinet that contains a set of ET200M also included the main console and auxiliary console, with drilling operations and drilling parameters of real-time display, electrical system operation control and display, sound and light alarm, fault indication. Control system can be completed more than five sets 600kW motor (which includes three sets Pump Motor, 1 winch machine and a turntable motor units) between the control and interlocking control; also includes a power cabinets, rectifier cabinet and drill Taiwan sensor data acquisition, control and alarm, fault display. In the drilling process, to hoist and turntable high reliability requirements, if the winch or wheel failure can not be repaired in a short time, there may result a large wall collapse incidents, which system has a redundant backup function.
3, the control system structure
Controller with a redundant backup feature, consists of two SIMATIC CPU 315-2DP module composition; use ET200M will be on-site input and output points connected to the controller via Profibus bus, and through Profibus bus with five sets ABB Inverter communication; Manager's Office with SIMATIC WINCC software via S7 protocol and controller communications; and an external controller through the MPI I SIMATIC TC35T in order to achieve remote maintenance.
4, system functions
Whole rig drilling process summarized as follows: <BR> winch device is mainly used for lifting, decentralization derrick, base, big hooks and drill pipe; turntable device for drill pipe in the buckle, the next button and rotate the drill pipe driven rock drill bit cutting ; mud pump device will inject high-pressure drill mud through the manifold, not only from lubrication, cooling the role of drill will be mixed with rock debris of the mud back to the mud cleaning system in order to re-use.
The main function of the entire rig the system include:
(1) through Profibus bus, to achieve S7-300 CPU and the communication between ABB frequency converter in order to complete the corresponding motor control. According to pass parameters to determine the number of PPO type, write the appropriate communication process. Critical drilling process to achieve safety interlock, if the failure to speak out in the console panel and light alarm, and the MP370 is given on the display panel prompts warning or failure.
(2) Pump control: operator to operate the drill room of the panel by the Secretary ET200M the Profibus-DP signals passed to the controller S7-300 CPU module, control the three fan mud pump, spray pump, mud pump main motor of the start, stop, speed, and the associated interlocking given protection. As the electrical power and requires the forced air-cooled. Mud fan starts, when the air pressure switch is closed to establish air pressure when the main motor may start the mud pump.
(3) winch control: the use of pulse encoder module by FM350 calculating hook height, the highest, lowest to limit and prevent "the next smash hit"; with "automatic control" function, can handle the speed for a given location in determining an automatic region (handle the whole trip 0 to 20%, 80% ~ 100%), in the region can be automatically run speed automatic hook and stop position; optional high-speed, low-speed, low-speed three speed options scope to adapt to different working conditions; in lifting, decentralization derrick, when the base load due to the weight of relatively large, use the "ultra-low speed" speed select mode (0 ~ 60rpm), but also in lifting, the lower levels, the system has the power braking functions, making operation smooth and reliable.
(4) wheel control: using Profibus-DP protocol communications, can control the speed dial for a given value of transducer, torque limit value, and gives inverter over-current, over voltage alarm.
(5) Software Redundancy: When due to power supply modules, backplane bus, the main station, hardware or software failures caused by CPU, redundant backup of the bus cable, redundant communications from the station interface, interruption or failure of redundant interfaces from the station When, through the SIMATIC Software Redundancy software - a simple software system can make a failure of the main CPU from the CPU take over redundancy, this standby system switching time of less demanding, while the use of redundant backup systems, or other special high-reliability of the system is not absolutely necessary (from the cost considerations) systems are more appropriate. Using this software, redundant backup methods can effectively improve the reliability of the system;
(6) Remote Control: The GSM wireless communication network enables remote monitoring and control. Application of oil drilling equipment, on-site specificity (high-reliability requirements, production and more remote site of a bad environment), on-site service can not be expeditious, cost of maintenance correspondingly larger. In the remote terminal via SIMATIC TELESERVICE software, available on-line real-time analysis cause of the malfunction and remote software upgrades. This can be more efficient use of resources, to provide fast service, much less maintenance costs and maintenance time and enhance the economics of the equipment;
(7) man-machine interface: two man-machine interface panels were set in the electric control room and driller room. By PROTOOL software configuration, the display device operating status, as well as the operation of the logic state of each motor to monitor the operation of field devices equipped with failure page is displayed for easy fault location and maintenance,
(8) Historical archiving and printing: Manager's Office by the set of the PC. Using SIMATIC WINCC software development, using Microsoft's SQL SERVER as the database management tool, VISUAL C to realize the historical archive data query, dynamic screen configuration can be realized reports, trends, alarm printing, analysis of data for managers to provide帮助.
Conclusion
The entire system implements a distributed centralized control of drilling equipment. Set in electrical control room of the S7-300 CPU, through on-site distributed I / O module acquisition device status and control the operation of field devices, with complex process control and routine interlock and protection functions, and realization of the scene through the two display panels equipment operating status of visualization, the system also has the historical archive and report print function, so that the whole system has a strong technological advantage and competitiveness.
Since the program is the first to use Siemens PLC control system, the entire system of communication using Profibus electrical network, the system driller room remote from the electronic control room (60m), the system set the communication rate of the initial 1.5Mbps, but in the scene found during debugging set driller room Distributed I / O from the station there are often a breakdown in communications phenomenon, and in accordance with design requirements of repeaters in the bus terminal and bus terminal connector resistors are placed in "ON" position. This allows on-site commissioning, troubleshooting and elimination spent a long time. But according to the manual search, communication speed should be up to 12Mbps, the system set the communication speed of 1.5Mbps communications should be reliable, but will the baud rate down to 500kbps, the system safe and reliable long-running and there is no communication failure phenomenon. This implies that the quality of communication problems. The analysis, from the electric control room in the driller room communication lines by the interference of large power lines.
How to network topology according to the structure of the hardware connections determine the bus system is reliable and safe operation of the communication rate and how to optimize these difficulties before us. Currently, Siemens has launched a Profibus system used to detect the quality of a dedicated communication equipment, according to the monitoring results to improve the structure and hardware topology wiring, easy installation, commissioning, fault location and maintenance; In addition, from cost considerations, use of optical fiber communication is also a feasible option. From the field device commissioning and operation of the circumstances, SIMATIC PLC control system reliability and flexibility for all to see, I believe we will have more equipment to use the SIMATIC control system.
(Editor：admin) |