Operation and maintenance of commercial and industrial natural gas systems
Numerous industrial and commercial companies are supplied with natural gas from the public network. In contrast to private households, they operate their own extensive pipeline networks or natural gas systems on their premises. The operators or users of these underground or exposed gas pipes are legally obliged to have their pipes regularly checked by a professional. With the regulations G 614-1 and G 614-2 of the DVGW, a new classification and evaluation scheme for leaks and defects comes into force.
In contrast to private gas house connections, natural gas systems and pipelines on factory or company premises, provided they are supplied via the public gas network, are treated as energy systems under the Energy Industry Act (Section 3, No. 15 EnWG). For some years now, they have been subject to the same technical rules and safety requirements as the networks of energy supply companies and network operators. The technical regulations of the DVGW as generally recognized rules of technology are to be observed by the operators (§ 49, paragraph 2 EnWG).
This classification results in special tasks and duties for industrial and commercial companies. However, numerous industrial and commercial customers are not aware that the regulations and requirements of energy law apply to the natural gas pipeline systems laid on their factory premises. This is especially true when gas supply or gas distribution is not part of the company´s core business.
A typical case are, for example, management companies / holdings of commercial real estate / industrial and business parks, but also small and medium-sized enterprises, with an insignificant number of companies not having records of the age, location and maintenance status of the existing gas network despite the corresponding provision in the DVGW set of rules .
At the same time, operational gas supply facilities in particular harbor considerable legal monitoring and maintenance risks for the operator. This primarily applies to their service life and the higher wear and tear due to stress and hazards in production buildings.
With the amendment of the regulations G 614-1 / 2, the above-mentioned due diligence standards of the plant operators with regard to their documentation obligations with regard to the course and location of gas pipes and gas plants are tightened.
The owners obligation to take technical precautionary measures from DVGW worksheet G 1010 is linked to corresponding monitoring obligations in G 614-2. This includes regular checks of the lines for leaks (preventive leak test) and the safe functioning of the individual components. The next section explains which parts of the system are affected by the obligation to have the system operator regularly inspected.
Legal and safety-related special position of operational gas distribution networks
The legal framework, according to which operators of industrially / commercially used gas supply systems have to comply, has been gradually expanded since the publication of the basic DVGW Gas Information No. 105. The DVGW reacted to the special legal and safety-related position of the industrial and company gas distribution networks in 2005. According to the standard, which has since been updated several times, the internal gas network consists of:
- the connection line to the network of the gas supplier
- the gas pressure control and measuring systems in the transfer station and, if necessary, other stations on the company premises
- the underground or exposed gas lines with their installations and connection lines in the operating facilities as well as the house installation lines for heating, hot water preparation and cooking in office and social buildings and the thermal process systems or gas devices
The legal and safety-related responsibility of the system operator of an industrially / commercially used natural gas system begins according to the DVGW rules behind the main shut-off device (HAE) and ends in front of the respective gas consumption device. In addition to the gas pipes, it includes all fittings and the associated equipment technology.
Monitoring and inspection obligations for operational gas network connections
The amendment or expansion of the DVGW set of rules to include the technical rules G 614-1 / 2 now obliges the operators of operational gas networks to regularly check the safety of their systems.
This effort is also justified for economic reasons. The ongoing upkeep of the pipeline network reduces the costs for maintenance and servicing, since leaks that occur can be detected and rectified promptly, thus preventing malfunctions.
The owners exercise of the inspection and maintenance obligations begins with ongoing careful documentation. To do this, the entire operational gas network must be recorded and mapped. All open and underground lines including fittings and connections are recorded. Subsequently, intersections and boundaries are defined (demarcation of the network to the supplier and consumer).
An annual visual inspection must be carried out with the aid of the documentation. As part of this visual inspection, the overall condition of the system is carried out in combination with the leak test of the lines and all connections. The entire system remains in operation. This control must be documented.
For commercial gas networks, the following regular inspection periods apply in accordance with the technical rules G 614-1 / 2 of the DVGW.
|Leakpoint Frequency per km||≥ 0,1||≥ 0,5||≥ 1|
|Operating pressure (bar)||Inspection period in years|
|>1 up to ≤ 5||4||2||1|
|> 5 up to ≤ 16||2||1||0,5|
After the leakage points have been located, they are evaluated and documented using the following leakage classes. If necessary, immediate measures are to be initiated or repair measures to plan.
Monitoring and testing by certified service providers
The operator obligations for owners of commercial or industrial gas networks are extensive. As described above, this begins with the professional documentation and inventory of your own gas network.
If, in the event of damage, the owner or operator cannot prove that the system was operated in accordance with the legal requirements, he will be fully liable for the damage incurred. A proper and professional examination by a DVGW-certified company is not only recommended for legal reasons. Regular inspections of the gas networks and installations reduce the maintenance and servicing costs of the operator in the long term.
Service for our industrial and commercial customers
As a DVGW-certified specialist company, Schütz GmbH Messtechnik has been active as a service provider in pipe network control for more than 50 years. In the past 20 years alone, the company´s gas detectors have circled the world more than ten times. The 25 employees walked and checked 400,000 kilometers of the gas pipe network. Many years of experience and the high qualification of our employees guarantee our
Competence and security in service. The company has also been working with a quality management system here for many years.
In addition to energy supply companies, the customers of the Services division also include industrial and commercial customers of all sizes. The following services are offered as part of the pipe network inspection according to the DVGW rules G 614 1/2 described above:
- Analysis of the existing gas network according to DVGW worksheet G 1010
- Advice on optimization
- Creation of factory plans (also digital) or the continuation / addition of existing plans. Comparison of the existing documentation with the current state
- Review of freely laid gas pipes in buildings outside area including verification and inventory
- Control of the underground gas pipelines including localization, measurement, classification and sketching of damaged areas according to the DVGW guidelines described above. Also with digital plans on request
- Creation of test, maintenance and inspection plans
- Training and qualification of your company´s employees in the areas of DVGW rules,
practice of pipe network control and device technology
- Creation of explosion protection plans and documents
- Measurement of proper odorization
As an additional service, Schütz Messtechnik offers industrial and commercial customers the inspection of pipelines for flammable and non-flammable technical gases. These include leak tests for hydrogen, acetylene, forming gas, nitrogen, argon, propane or compressed air.