DE3835901C2 - Procedure for replacing a pipe laid in the ground - Google Patents

Description

The invention relates to a method for exchanging a Soil laid old pipeline through a new ver laying pipeline.

Pipes laid in the ground, for example water or gas pipes from cast iron pipes, show over time Signs of aging so that it may become necessary to replace the old pipeline with a new one. Such a Exchange should preferably take place in such a way that the Soil does not have to be dug up as this is done with a involves a lot of work and is therefore costly and since such earthworks, especially in the area of Road network, require an intervention in the flow of traffic. A possible influence on neighboring is also disadvantageous arranged transport or communication lines in the ground.

It is already a process for exchanging pipes confesses, in which the new pipeline simply in the old Pipeline is inserted. However, this procedure has the Disadvantage that the inner diameter of the new pipeline inevitably less than the inside diameter of the old pipe line, which increases the transport capacity for gas or Water diminished.  

Improved methods with which the disadvantages of this known method can be countered are disclosed in GB 21 52 624 B, GB 21 24 325 B and GB 20 92 701 B. A device according to these prior publications is shown in FIG. 7 of the drawing. In FIGS. 8 and 9, the use of this known device is shown.

The aforementioned prior publications disclose a process and a device for exchanging pipelines, wherein the new pipeline to be installed at the rear end of a Expanding body is attached, the cylindrical housing has an outer diameter that corresponds to the outer diameter of the old pipeline laid in the ground. The up wide body will be installed together with the new one Pipeline driven forward, with the head of the Expansion body penetrates into the old pipeline and this progressively breaks open, creating an expanded channel to Inclusion of those to be relocated following the expansion body Pipeline is created. This way the old one Pipeline replaced by the new pipeline.

From Fig. 7 it can be seen that a rear end of an expansion body 4 a with a housing diameter larger than the outer diameter of the old pipe 1 a either with a new pipe 9 a for immediate replacement of the old pipe or with a sleeve 14 for receiving and Protection of the new pipeline is provided.

Referring to FIGS. 8 and 9, the expander body 4 a view with a the expander propulsive air cylinder ver, the (a compressor 8) is connected via a compressed air line 7 a to a compressed air source, the compressed air line 7 a by the new pipe 9 a or runs through the sleeve 14 . At the front end of the expansion body, a rope 3 a is attached, which runs through the old pipeline and is connected to a winch 2 a.

The expanding body 4 a is moved forward in batches by breaking open the old pipe by using the thrust impulse directed against the holding force of the cable winch and from the compressed air source. Since the largest outer diameter of the expansion body is larger than the outer diameter of the old pipeline, the fragments of the old pipeline are pressed outwards, creating a channel, the diameter of which exceeds the outer diameter of the subsequent pipeline or sleeve to be newly installed. In this way, the insertion of a new pipe having the diameter of the old pipe is facilitated by the resulting annular gap as a result of the different diameters of the expansion body and the new pipe to be installed.

The known method is a useful and sensible method to set pipes embedded in the ground. However, a detailed assessment of this known method reveals some disadvantages. The disadvantages listed below exist both when a new pipe is pulled into the ground through the expansion body and when a sleeve is inserted:

• 1. If a sleeve is not used (ie a new pipeline to be installed is attached to the rear end of the expansion body for direct replacement):
  • a) Due to the retraction of the compressed air line and the subsequent work process, damage to the paint or coating on the inside of the new pipeline to be drawn in may occur, especially if other components pass through the pipeline in addition to the compressed air line.
  • b) Since the exhaust air is discharged into the interior of the pipeline to be installed, parts of the lubricating oil in the air can deposit on the inner surface of the pipeline to be installed and contaminate it (the lubricating oil must be added to the compressed air to ensure perfect piston movement) . If one uses an additional exhaust air line to avoid this problem, this not only worsens the efficiency, but also limits the operation of the compressed air cylinder due to the reduced outlet cross section. This would require a larger number of compressed air lines, which in turn would increase the risk of damage to the inner surfaces of the pipeline to be newly installed.
• 2. If a sleeve is used (it should be noted that the new pipe to be laid is inserted into the sleeve after it is in the ground instead of the old pipe):
  Since the sleeve attached to the expansion body has an inside diameter that exceeds the outside diameter of the pipe to be newly installed, a larger outside diameter of the expansion body is necessary than in the method described above without using a sleeve. As a result of the larger diameter, however, greater pressure must be exerted on the ground, as a result of which the efficiency deteriorates. In addition, the consequences of this increased pressure on the soil in the form of higher soil pressure and vibration must not be overlooked. In particular, in cases in which there are further pipes in the ground in the immediate vicinity, there is a risk that these pipes will be displaced laterally in an undesirable manner or that pipe connections will loosen as a result of the pressure.

The invention is therefore based on the object to avoid the disadvantages mentioned above and a ver improved procedure for the exchange of pipelines create where the inner surface of the new to be relocated Pipe is not damaged, stained or soiled and where negative influences on neighboring soil layers be avoided.

For the technical solution of this task is pre suggest that an auxiliary pipeline with a roughly that Corresponding diameter of the new pipe to be installed Diameter at the rear end of an expanding body is attached, whose outer diameter is larger than that Diameter of the old pipeline that the expansion body is propelled, its head into the old pipe line penetrates and this expands or breaks open, whereby an expanded channel for receiving the expander following auxiliary pipeline is created and that the new too Laying pipeline at one end of the auxiliary pipeline attached and the auxiliary pipeline under gradual Er put through the new pipe to be laid out of the sewer is moved out.

With the inventive method, damage to the Painting or coating the inner surface of the avoided replacing an old pipe with a new pipe. Even if provide the jacking device with a compressed air cylinder stains and damage to the inner upper area of the new pipe due to the precipitation of dirt particles (lubricating oil particles in the exhaust air) avoided, so that after the exchange, a cleaning of the new pipe is no longer necessary.

In particular, an auxiliary pipeline can be used for replacement a roughly the diameter of the pipe to be installed  line corresponding diameter is used, the outside diameter of the auxiliary pipeline can be chosen smaller than an appropriate sleeve for a new pipe of the same diameter sers, so that the necessary driving energy for the forward movement is correspondingly smaller. This will make the Influence of neighboring soil layers reduced.

In addition, the auxiliary pipeline used can be used to carry out further procedures can be reused, so that the The inventive method is less expensive than that known method, in which the once in the ground drawn sleeve is left there.

In the drawing are execution described below illustrated examples of the method according to the invention, and show:

Fig. 1 is a schematic representation of a method of exchanging an installed in the soil pipe;

FIG. 2 shows the process shown in FIG. 1 at a later process stage;

Fig. 3 is a simplified sectional view through a method according to both Figures 1 and 2 used auxiliary pipe.

Fig. 4 in a partial section the structure and the connection technology of two pipes to be newly installed;

Fig. 5 in a simplified representation of a variant of the inventive method;

Fig. 6 is a simplified representation of a further variant of the inventive method;

Fig. 7 is a view of a known and therefore the old with the prior art associated with the expansion head for expanding or breaking pipelines;

Fig. 8 is a known and therefore ge prior art method for replacing a buried old pipeline;

Fig. 9 is a further illustration of the known method according to Fig. 8.

The method according to the invention is explained in the following with reference to FIGS. 1 and 2, FIG. 1 replacing an old pipeline 1 laid in the ground with an auxiliary pipeline 5 and FIG. 2 replacing this auxiliary pipeline 5 with a new pipeline to be installed 9 shows.

The individual process steps are structured as follows:

• 1. At both ends of the pipe string to be replaced pits are dug out of the ground, one at a time Starting pit K1 and a target pit K2. The pits K1, K2 continuous pipe sections are removed.
• 2. A winch 2 is installed in the target pit K2 or in its vicinity. Starting from the target pit K2, a rope 3 of the winch 2 is pulled through the old pipeline 1 to the starting pit K1.
• 3. An auxiliary pipe 5 , which is composed of individual auxiliary pipes and has approximately the length of the pipe string to be replaced of the old pipe 1 , is attached to the rear end of an expansion body 4 , the expansion body 4 and the individual elements of the auxiliary pipe 5 by a wire 6 are held together, which runs through the auxiliary pipeline 5 . The wire 6 is stretched between the rear end of the expansion body 4 and the rear end of the auxiliary pipeline 5 and attached to these ends. In addition, a compressed air line 7 is passed through the interior of the auxiliary pipe 5 and connected on the one hand to the expansion body 4 and on the other hand to a compressor 8 .
• 4. The cable 3 of the cable winch 2 is fastened to the front end of the expansion body 4 in order to guide the expansion body 4 to the beginning of the pipeline 1 in the starting pit K1.
• 5. As a result of the thrust pulse of a compressed air cylinder arranged in the expansion body 4 , the expansion body 4 is moved against the holding force of the cable winch 2 in the direction of the target pit K2, a head of the expansion body 4 penetrating into the old pipeline 1 and the latter acting through a radially outward direction Pressure expands or breaks open. At the same time, the auxiliary pipeline 5 drawn by the expansion body 4 is gradually drawn into the fragments of the old pipeline 1 , while the expansion body 4 is working on from the starting pit K1 to the target pit K2.
• 6. After reaching the target pit K2, the expansion body 4 is separated from the auxiliary pipeline 5 . Likewise, the compressed air line 7 and other connections are removed from the expansion body 4 and pulled out of the auxiliary pipeline 5 . The method steps described above are shown graphically in FIG. 1.
• 7. A pipe section of the newly to be laid pipe 9 is attached and at the end of the auxiliary pipe 5 in the starting pit K1 provided in the direction of the target pit K2 by means of a abgestotzten in the starting pit K1 pusher 10 inserted, wherein at the same time the whole auxiliary pipe 5 in the direction of Target pit K2 is moved until a first pipe section of the auxiliary pipeline 5 can be removed there.
• 8. New pieces of pipe are placed one after the other in the starting pit K1 on the respective previous and already inserted pieces of pipe and inserted by means of the pusher 10 in the direction of the target pit K2, whereby the auxiliary pipe 5 is replaced piece by piece with pipe elements of the new pipe 9 until the new pipe 9 extends from the starting pit K1 to the target pit K2. If 5 short Rohrele elements are used for the auxiliary pipeline, these can be removed piece by piece in the target pit K2. The method steps described above correspond to the graphic representation of FIG. 2.

The method steps described are independent of the type of drive of the expansion body 4 . This can also be driven in other ways than by means of a compressed air cylinder. The requirement of connection to a drive source, be it via a compressed air line or a cable, is in any case.

Fig. 3 is the structure of the auxiliary pipeline 5 to take ent. The auxiliary pipeline 5 is composed of individual pieces of pipe, each having at one end a sleeve with a smaller diameter and are provided at its other end with a nozzle into which the sleeve can be inserted into the closest pipe section. Since the auxiliary pipeline 5 is moved in the ground, its outer surface should be machined as smoothly as possible. On the other hand, the design and the material used for the individual pipe sections of the auxiliary pipeline 3 only play a role in that a sufficient tensile strength in relation to the tensile force applied by the expansion body 4 and a sufficient compressive strength in relation to the compressive force generated by the Schubvor device 10 when Inserting new pipe pieces must be ensured. The pressure of the surrounding soil must also be able to be safely absorbed.

FIG. 4 is connection screw nuts to remove a between successive pipe sections of the new pipeline 9. The pipe jacket of the pipe sections consists of an extensible cast iron produced by centrifugal casting. The inner lateral surface of the pipe pieces is lined with a water mortar 11 , while a concrete reinforcement 13 is used as the outer lateral surface of the pipe piece, which is reinforced by baskets 12 welded together from steel rods.

In the illustrated in Fig. 5 variant of the process the elements of the new pipe 9 are attached to the rear end of the auxiliary pipe 5 so that pulling upon removal of the auxiliary pipeline 5 by means of a hinged at the rear end of the auxiliary pipe 5 the rope on the winch 2 the individual elements the new pipeline 9 are drawn into the channel formed by the expansion body 4 . In this way, a pushing device in the starting pit K1 is unnecessary. Since in this variant of the method, the auxiliary pipeline 5 and the new pipeline 9 are pulled through the channel widened by the expansion body 4 , no strong drive, in particular no pushing device, is necessary, so that the jacking system for the auxiliary pipeline 5 is sufficient.

In FIG. 6, a further variant of the method is shown for replacement of pipes, in which an individual tube elements of the auxiliary pipe 5 are assembled only in the start pit K1. This method is used in particular when, due to space constraints at the floor level, assembly of the auxiliary pipeline 5 is not possible there.

Reference list

1

old pipeline

2nd

Winch

3rd

rope

4th

Expanders

5

Auxiliary pipeline

6

wire

7

Compressed air line

8th

compressor

9

new pipeline

10th

Pusher

11

Water mortar

12th

basket

13

Concrete reinforcement

K1 starting pit

K2 target pit

Claims (4)

1. A method for replacing an old pipeline laid in the ground by a pipeline to be newly installed, characterized in that an auxiliary pipeline ( 5 ) with an approximately the diameter of the new pipeline ( 9 ) corresponding diameter at the rear end of an expansion body ( 4 ) is attached, the outer diameter of which is larger than the diameter of the old pipeline ( 1 ), that the expansion body ( 4 ) is driven forward, the head of which penetrates into the old pipeline and expands or breaks it open, thereby creating an enlarged channel to accommodate the expansion body ( 4 ) following auxiliary pipe line ( 5 ) is created and that the new pipe ( 9 ) at one end of the auxiliary pipe ( 5 ) be fastened and the auxiliary pipe ( 5 ) with gradual replacement by the new one to be installed Pipeline ( 9 ) is moved out of the channel. 2. The method according to claim 1, characterized in that the expanding body ( 4 ) is driven forward in batches. 3. The method according to claim 1 or 2, characterized in that the new pipe ( 9 ) behind the auxiliary pipe ( 5 ) by means of a pushing device ( 10 ) is pushed into the ground, the pushing device ( 10 ) being anchored in a pit, which is designed to expose one end of the old pipeline ( 1 ). 4. The method according to claim 1 or 2, characterized in that the auxiliary pipeline ( 5 ) with simultaneous entrainment of the new pipeline ( 9 ) by means of a cable winch ( 2 ) is pulled from the ground.