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Maintenance and diagnostics

Maintenance and diagnostics

NET4GAS has been providing safe and reliable natural gas transmission throughout the territory of the Czech Republic for more than forty-five years. This is due in particular to the high demands placed on the quality of construction, operation and maintenance, as well as long-term technical and technological development.

All gas infrastructure is subject to thorough regular inspections, not only during construction, but also during subsequent operation. Each piece of equipment is subject to highly demanding tests prior to its commissioning, and it can only be put into operation if it passes all these tests with positive results. A supervision and maintenance program is carefully observed throughout the infrastructure in its entirety immediately following commissioning.

NET4GAS is aware of its environmental responsibility, and it therefore uses state-of-the-art equipment and technologies that minimize the environmental impact of maintenance activities.

Transmission system maintenance

NET4GAS has specialized technologies and a team of employees with long-term know-how to ensure the operability of the transmission system. They ensure the following activities for the transmission systém:

  • Repairs and installation of all gas infrastructure
  • Operation and maintenance of existing corrosion protection technology and equipment in accordance with valid technical rules and standards
  • Operation and maintenance of telemetry equipment, verification of parameters, and supervision over technical condition of telemetry equipment within transmission system
  • Technical diagnostics and special measurements

Transmission system diagnostics

A variety of diagnostic methods is available for the assurance of safe and reliable gas transmission. Stringent quality requirements are already set at the time of construction of gas pipelines and other gas infrastructure. Adherence to these requirements is strictly controlled. Important information on the operation, maintenance, and technical condition of the monitored equipment is subsequently collected during operation.

The basic manner of pipeline diagnostics is internal inspections with an inspection/cleaning tool, a so-called “intelligent pig”, which passes through the pipeline without transmission interruption. A comprehensive approach also includes controlling the quality of pipeline insulation, accurate localization of all objects using the Geographic Information System (GIS), and careful maintenance of a database of pipeline status data from its construction up to the present. Optimum use of all information is ensured by the pipeline integrity management system (PIMS).

The established diagnostic system also supports the safe and reliable operation of the compressor stations, as it contributes to accident prevention and adapts the maintenance and repairs to the actual technical condition of the main technological equipment. Diagnostics of turbines and compressors is based on vibration diagnostics, which determines the mechanical condition of the machines and the nature of possible defects based on the measurement and evaluation of vibrations. Other methods comprise the measurement of turbine and compressor performance parameters, tribodiagnostics, which determines the condition of machines with respect to lubrication oil contamination, boroscopy, allowing for the internal inspection of machines without their disassembly, as well as thermovision, which identifies an imminent defect according to the abnormal heating of a given part of the machine.

The current trend is to link the monitoring and diagnostic systems with control and information systems, to focus on operational and maintenance efficiency, and to conduct maintenance while taking into account the results of systematic monitoring of the reliability of individual technological parts and the assessment of operational risks.

NET4GAS also offers selected specialized services to external entities - see the Supplementary services section.