Sewer inspection
Under sewer inspection in the public sector is generally understood to mean a TV Befahrung the pipe network of sewers . The video inspection of the sewer system is usually commissioned by cities and municipalities to prevent infrastructural damage such as burst water pipes and flooding in inner-city areas. Sewer inspections are also carried out in private households, but other inspection methods are used here. Instead of the sewer inspection trolley, due to the thinner pipe diameter, push camera systems are used to make the inside of the pipe visible with the aid of a satellite camera.
Sewer inspections are also carried out in order to clarify the precise responsibilities in the event of water damage . According to the current legal situation, the owner of an affected supply line is responsible for the removal of any damage to it. A large part of the water pipes are owned by the municipalities, however, according to a decision by the Federal Court of Justice (BGH) on September 11, 2014 , homeowners are themselves responsible for a controllable risk area. In individual cases, a leak test by video inspection is used to determine which area of responsibility a problem falls into and which party is made liable for it.
device
Today the inspection vehicle is essentially equipped with a sewer inspection camera (also called a shaft camera) and around 50–1000 m of cable. The data is sent to a computer or video recorder to record video data, images and alphanumeric inspection data ( Isybau , DWA data).
The camera is designed accordingly and mounted on a trolley, which is inserted into a sewer shaft after a sewer cleaning (sewer flushing ). The camera head is directed forwards during the inspection run. If the driver sees branches on his monitor or damage to the pipe wall, pipe bottom, etc., he pans the camera and creates entries in the recording software .
Action
The majority of public sewers have an inside diameter (mm) of DN 200 to DN 1800. The camera trolley moves through the sewer pipe at a set speed. With the help of special software, the images are generated and reports are created so that the damage can be viewed later at any time based on the recordings.
In the case of smaller nominal widths, i.e. the property, house drainage or house sewer system (DN 150-DN 200), a so-called satellite camera is pushed through the pipe. This can be done manually or with the help of a special camera constellation, which makes it possible to position the camera in the house connection from the main pipe with the help of a special push rod, an extra winch and an operating device. This option is used in particular if there is a connection shaft on the property.
The inspection from the main sewer usually only serves to determine the proper condition of the connection line up to the property boundary. According to the waste water statute, the house owner is usually responsible from the property line.
Newer methods of sewer inspection meanwhile completely scan the sewer pipe system to be inspected. Fully spherical, semi-spherical or cylindrical wide-angle cameras are used for this purpose. When recording the condition with these systems, the source of the error “non-filmed damage patterns” does not occur due to the system, as the entire attitude is generally recorded. Identifying and describing the damage patterns (alphanumeric status recording) is still done manually in the same way as conventional TV traffic, but no longer on site on the street, but in the office. As a result, this method also has a corresponding potential for error, with the damage log being able to be checked at any time on the basis of the available image data, and a new filming can thus be dispensed with. In order to minimize this potential for errors, the integration of image recognition algorithms in these systems is possible and the focus of current research projects.
Web links
- kanalinspekteure.de - Information on sewer inspection
- OZEK - Development and testing of a digital image recognition and image processing method for the objective assessment of the condition of sewer systems . RWTH Aachen
Individual evidence
- ↑ Camera inspection. In: Rohrreinigung Berlin from the specialist Neo Concept. Retrieved October 25, 2019 (German).
- ^ Judgment of the III. Civil Senate of 9/11/2014 - III ZR 490/13 -. Retrieved October 25, 2019 .
- ↑ messen-nord.de ( Memento of the original from January 6, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
