|
|
All the current standards and regulations dealing with the position and arrangement of lines for new installations are based on the single installation of the lines, and these are the subject of the following discussion. However, in place of single installation (Abschnitt 2.1.1) of lines there is the possibility in public areas and especially at crossings of traffic roads and waterways of multiple installation in the same line and gradient (directly … |
||||
|
|
Fine trees were once a sign of wealth and vitality of a town. After this had long been forgotten and trees became the victim, for instance, of the improvement of street traffic, there has been an increasing tendency for some years in the towns and communities of the Federal Republic of Germany to plan and undertake measures for the introduction of greenery - even in connection with easing traffic flow. Trees are an important component of the city … |
||||
|
|
In order to maintain the functional capacity of human social structure and to ensure further urban development, supply and disposal lines (product lines) for transport and … |
||||
|
|
In the following, direct installation will be understood to be the immediate installation of the product line in an underground cavity created using trenchless methods. In this form, the product line must be able to withstand the loads in construction and operation state (Abschnitt 14). |
||||
|
|
Telecommunication cables (Abschnitt 1.1.5.1) are usually supplied on drums and should be installed as the longest possible string without interruptions taking the manufacturer's bending radii into account. Installation of telecommunication cables in cable casing pipes is carried out by:
Copper cables are generally pulled in with a cable pulling winch using a special pulling grip (Bild 2.1.2.1) or, for cable diameters > 30 … |
||||
|
|
Casing pipes for power cables must be placed accurately in such a way that the bending radius of the casing pipe does not fall below the minimum permissible bending radius of the cable to be installed - in order not to endanger the operational safety of the cable. For this reason, when using low and medium voltage cables, the radii mentioned in Tabelle 2.1.2.2 for cable casing pipes, should be adhered to but in place of the external cable diameter … |
||||
|
|
(Image: Pulling in a DHC with skids in a casing pipe [FI-Brugg]) Flexible district heating pipelines (Abschnitt 1.1.3), especially so-called district heating cables (DHC), are usually placed in a casing pipe (Abschnitt 2.2). Besides the aspects mentioned in Abschnitt 2.1.2, the following must also be considered [FI-Brugg] :
|
||||
|
|
The installation of drains and sewers in a casing pipe is especially recommended when the potential danger of exfiltrating sewage to the environment is very high. This is applicable especially for drainage systems in water catchment areas (Abschnitt 1.1.4.1). In this case, of the combination may be termed a double-walled piping system that, according to ATV-DVWK-A 142 [ATVA142d] is made up of two separately produced un-linked pipes. In double-walled … |
||||
|
|
Whether a gas or water pipeline is placed in a casing pipe when crossing traffic lanes is determined mostly by the materials used and the joints of the product pipes. In general, importance is placed first on the safety aspects of the respective case; for instance, a casing pipe for a water pipe is meant to prevent the washing away of the traffic lanes due to leaking water in the case of a pipe fracture. According to the DVGW working sheet W 305 [… |
||||
|
|
(Image: Installing a water pipeline in a casing pipe (annular space grouted) with reference to [DVGWAGW307] [Image: S&P GmbH]) In this case, the casing pipe provides the multiple functions of accepting the product pipe or cable, protecting them from external loads and, in case of failure, to act as a protective covering for the product pipe or cable. In addition, in connection with trenchless method, it serves as a means to create and/or support the … |
||||
|
|
A pulling head is placed at the end of the first pipe in the starting shaft, the winch cable is fastened and the pipe is pulled into the casing pipe until only the pipe connection region remains in the starting shaft. The next pipe is connected to it in a tensile restrained manner, e.g. by welding for steel pipes or for plastic pipes, by using screwed joints, special plug joints (Abschnitt 13), or tensile restrained steel slide rollers with tension … |
||||
|
|
For this method, the winch cable is pulled from the target shaft through the product pipe and the pulling force is applied to the last pipe still in the starting shaft by means of a pressure plate or cross piece situated at the rear end of the already jointed continuous pipe. In this way, the pipes are only … |
||||
|
|
In this insertion method, the pipes are pulled into the casing pipe individually and connected to each other at site. The fixing of the pipe string in position is carried out by fastening the first pipe in the target shaft. (Video: Discrete pipe process - Pulling-in of single pipes into the section) For pulling in pipes, use can be made, for instance of inflatable packers or a special pulling-in body onto which the pipe is pushed and whose end is provided … |
||||
|
|
|||||
|
|
In the pushing-in process, the individual pipes or pipe section are connected in the starting shaft and the lengthened pipe string is pushed in by the length of the added pipe(s). (Video: Pushing-in of discrete pipes by means of a hydraulic cylinder wired inside the neighbouring sewer - Principle sketch) The simplest method is by pushing in the pipe by hand using simple aids. This process, however, can only be used to a limited extent for:
|
||||
|
|
In contrast to the pulling-in and pushing-in processes, in which the required forces are applied directly to the pipe, in the drive process the forces are applied to special conveying devices onto which the pipes are placed or from which they are suspended. The driving-in process is almost exclusively utilized in manaccessible cross sections using the following special equipment:
|
||||
|
|
When undertaking the later insertion of product pipes into casing pipes previously installed using a trenchless method (Abschnitt 2.1.2), the type of installation varies depending on the loading of the individual pipes or pipeline caused by the installation as follows [Stein83c] :
|
||||
|
|
Grouting the annular space between the directly installed casing pipe or host pipe and a later installed product pipe can be beneficial depending on the local situation and application (e.g. crossing of steel gas and water pipes and pipes of ductile cast iron under traffic installations such as rail lines, roads and waterways [DVGWAGW307]). Grouting the annular space can achieve the following for the product pipe:
|
||||
|
|
In the following, single installations will be understood to be the separate installation of individual lines in a prepared line and gradient (e.g. in the road cross section to DIN 1998 [DIN1998] (Abschnitt 1.2)). Such installations can be carried out by means of (Bild 2)
|
||||
|
|
In connection with the following discussion of multiple installation, the term direct installation will be understood to mean the direct combined pulling-in of several product pipes and/or cables in the underground installed and temporarily stable cavity with the aid of a trenchless installation method (Abschnitt 5) (Abschnitt 6) (Abschnitt 7.1) (Abschnitt 8.1) (Abschnitt 9.1). The lines must be able to withstand the loads during the construction … |
||||
|
|
In loose installation of lines, usually cables, they are either pulled in or blown in (Abschnitt 2.1.2) separately one after the other or together (not bundled (Abschnitt 2.2.1)) in a single operation. In this case, adherence to spacing and arrangement is consciously dispensed with in order to have the possibility of removing individual lines for replacement by pulling them out at a later time (Bild 2.2.2.1) (Bild 2.2.2.1).
|
||||
|
|
In bundled installation, the pipes are tied together at specified spacings by means of plastic adhesive strips, cable binders or skids (Bild 2.2.2.2) (Bild 2.2.2.2) (Bild 2.2.2.2) (Bild 2.2.2.2). This ensures controlled guidance and, to a large extent, the maintenance of a prescribed bundle diameter. It is no longer possible to exchange individual lines by pulling them out.
|
||||
|
|
In group installation, the individual product and casing pipes are arranged and fixed in a controlled manner by means of multiple clamps or spacers and are inserted into the host pipe with the aid of rollers or skids (Bild 2.2.2.3) (Bild 2.2.2.3) (Bild 2.2.2.3) (Bild 2.2.2.3) (Abschnitt 2.1.3).
|
||||
|
|
(Image: Variations of the trenchless installation of lines) Host pipes are underground non-man-accessible or man-accessible pipes for the later insertion of several product lines or casing pipes of the same or different type. For trenchless installation and depending on the method, for the creation and/or support of the cavity that has been installed, host pipes must also be able to withstand the loads in the construction state (Abschnitt 14). If the … |
||||
|
|
Utility ducts are underground systems for the orderly installation of supply and/or disposal lines utilizing a structural shell for line fastening or support using dowels (Bild 2.2.3) (Bild 2.2.3), clip rings (Bild 2.2.3) (Bild 2.2.3) (Bild 2.2.3), multiclamps (Bild 2.2.2.3) or line supports (Bild 2.2.3) (Bild 2.2.3) (Bild 2.2.3). The spacings between the lines are not filled in order to maintain the possibility of later access.
|
11094 search results:
