MONITORING AND DIAGNOSTICS SYSTEM

of the pipelines stress-strain behavior (static deformations and temperature)

Need for the pipelines state monitoring and diagnostics

The main pipelines are intended for transportation of various substances (solids in the form of a slurry, liquids, and gases).

The transportation is driven by the pressure drop in the pipe cross-sections. During the transportation, the substances may heat up, thus heating the pipeline itself. The pressure and temperature may exceed the permissible values creating conditions when pipeline deformation or even failure may occur.

There is probably no need to explain the danger of main pipelines failure and its consequences. Thus, the need for introduction of a pipeline stress-strain behavior measuring and monitoring system to prevent hazardous conditions becomes obvious.

Application scope of the system 

The system is intended for measurement and control of pipelines stress-strain behavior. The system can be used in different branches of industry, including those controlled by Rostekhnadzor, as a standalone system or as a part of other system. The use of the system ensures efficient and safe pipeline operation through the prevention of emergency situations and repair and maintenance works optimization.

System structure (composition)

—   Resistive strain sensors (deformation measurement);
—   ZET 7110 Tensometer-CAN smart units;
—   Thermocouples (temperature measurement);
—   ZET 7120 smart units;
—   ZET 7176 (Ethernet – CAN) or ZET 7174 (USB – CAN) interface converter;
—   Power supply unit for ZET 7176 or ZET 7174 unit;
—   ZETLAB SENSOR basic software package supplied with ZET 7176 or ZET 7174;
—   ZETLAB Registration recording and reproduction program;
—   ZETVIEW SCADA software. Dedicated specialized software may be developed for a specific project.

Operating principles of the system 

Resistive strain sensors are attached to the pipeline section to be controlled; they serve as deformation measuring instruments; a smart unit (strain sensor) ZET 7110 Tensometr-CAN is connected to each resistive strain sensor. Then, ZET 7110 units are connected with a cable and are connected to the ZET 7176 (Ethernet – CAN) or ZET 7174 (USB – CAN) interface converter, then to a PC with specialized software installed.

The smart strain sensor consists of a resistive strain sensor (strain gauge bridge) and a measuring module. The ZET 7110 Tensometer-CAN strain sensor performs measurement of the relative deformation using the resistive strain sensors, the sensor measuring module converts the signal from the sensor to the values of force, strain, or pressure. The obtained values are transmitted to a PC screen via CAN 2.0 interface, which makes it possible to use the sensors without any additional setup of the measuring channels.

Using the SCADA specialized software, the user may create flexible and scalable applications for measuring, controlling, and testing with minimum time costs. ZETView SCADA system is used as a system for data retrieval and processing from the devices connected to the PC, strain sensors in this case.

The whole parameter measuring process is displayed on a PC screen in real time, and is logged for subsequent analysis and storage.

Temperature is measured in a similar way. First, the temperature of thermocouples which are installed on the controlled pipeline section (glued or welded) is measured directly, then the ZET 7120 smart units are connected to the thermocouples and, through an interface converter, to a PC for data display on the screen.

Also, the ZET 7121 can be used instead of the ZET 7120 smart units, depending on the tasks set.

The ZET 7110, ZET 7120, and ZET 7121 units are registered in the Registry of measuring equipment under No 52802-13.

The whole equipment complex has a full package of the permissive and operation documents required according to the applicable standards.