| US3546890A | 1970-12-15 | |||
| SE8904213A |
| 1. | A method to steer and to observe the advancement of tubes (5) that have to be driven into the soil, in which method tubes are joined together in succession and the main tubepushing force is transmitted to the rearmost tube (5) from a pushing power unit (11) placed in the tunnel opening, characterized in that to the front of the tube line a soil cutting and essentially knifelike arm (1), (6) is fastened, which extrudes from the ground and advances along with the tube head and by means of which contact is established from the ground to the tube head. |
| 2. | A method according to patent claim 1 characterized in that the tube advancement direction is changed by transmitting over the arm (1), (6) to the tube line head section forces to deviate the tube head (4) from the direction of advancement. |
| 3. | A method according to patent claim 1 or 2 characterized in that, on turning arm (1), (6) around its vertical axle, a change of direction of the arm advancement is produced, which change is transmitted over the arm fixing parts (2,7) to the tube line head to change its direction, too. |
| 4. | A method according to any of the above patent claims 1 3 characterized in that the arm can be detached from tube head (4) and remounted in the tube head again. |
| 5. | A method according to any of the above patent claims 1 4 characterized in that a motordriven working machine (9) or device (8) is used to steer the arm (1,6) or to generate forces and loads which are to be transmitted to the arm. |
| 6. | A method according to any of the above patent claims 1 5 characterized in that through a channel or similar, formed in the arm, pipes or cables are taken to the tubes in the soil. |
| 7. | An apparatus according to any of the above patent claims 1 6 characterized in that it is an oblong, essentially flat arm (1,6) with a cutting edge and fixing parts (3) in its one end, for grabbing of it and transmitting forces to it, and fixing parts (2,10) in its other end for attaching the said arm to the tube line head. |
| 8. | An apparatus according to patent claim 7 characterized in that the arm (1,6,12) is hollow for taking different kinds of pipes and cables through the arm to tube line (5) or to its head (4). |
The invention relates to a steering method of a tube line that has to be driven into the soil, by means of which the tube line is driven into smooth soil of uniform quality and so deep with res¬ pect to the ground that it is possible to force a soil-cutting arm from the tube head up to the ground in order to indicate the tube head location and to be able to transmit from the ground to the tube head forces to change its direction.
Previously known are steering systems, which are utilized by tun¬ nel building, by means of which the travel direction of the tube head is observed at the ready-made tunnel opening with the aim to change the its direction through the tunnel opening upon need. On short driving distances the tube line is given a sufficiently accurate starting direction, whereat the tube line generally sustains its direction with acceptable accuracy.
When the tube line must be driven longer distances horizontally into the soil, for instance_50 meters without intermediate exca¬ vations, and if the ground is soft soil or marshland, the now known methods cannot be applied to longer tube lines. If a stee¬ ring apparatus is placed at the tube line head to turn the head upon need, the weight of the head becomes so heavy that it tends to sink in watery peatsoil in spite of steering. Neither can the steering be accomplished successfully in marshy soil, because the tube line does not get necesary support from the surrounding soil. With an accurate initial alignment it is possible to advance in peatsoil ab. 50 metres if one has succeeded to produce such a tube line weight that buoyancy does not tend to lift up the tube line and its weight does not tend to press it down.
With the method and apparatus according to the invention a de¬ cisive improvment in the above described disadvantages is achieved and the invention is characterized in what is presented in the patent claims.
The most important advantages of this invention can be considered that the location of the tube line head can be observed constantly along with its advancing, head-steering forces can be controllably transmitted the head and an arm, which reaches up to the ground, can be temporarily detached if it hits obstacles. Furthermore, if this arm is hollow, it is possible to transmit through it along pipes to the drilling head different functions and driving energy.
In the following the invention is more closely defined with refe¬ rence to the drawing, where
Fig. 1 is arm-steered driving of a tube line into the soil. Fig. 2 is the use of machines by steering. Fig. 3 is a cross-section of an arm. Fig. 4 is a cross-section of a hollow arm.
Figure 1 shows the driving of tubes 5, joined together in succes¬ sion by welding, into the soil starting from the tunnel opening 14, where a hydraulic cylinder 11 is used as a power unit to push the tube line. The first tube is furnished with a head cone 4, whereat the tube displaces soil aside. The soil must be soft, wet clay or marshy land so that displacement can take place. In front of the head component there is another cone 2, onto which a knife element 2 is fastened, which reaches up to the ground. Since the soil must be soft, the knife element can cut a narrow gap for it¬ self into the soil above the tube line. Practically, the driving depth of the tube can be about 2 meters. In the upper part of the knife element there are fixing parts 3, from which the knife can be lifted, pressed down or turned in order to produce different steering functions. The knife can sometimes also be lifted up and pressed down mechanically later on, whereat the cone parts attach to another. Turning the knife leads to sideways change of the head portion direction, because the flat knife element functions as a rudder while advancing in the soil.
Figure 2 shows steering with a working machine 9 by means of knife arm 6. The arm 6 is fastened to the shovel from part 3, whereby for the arm a vertical motion and a small turning motion is pro-
duced with the working machine. A combustion engine operated vibrator 8 is mounted in the upper end of arm 6, by means of which vibrator the advancement of the head can be improved remarkably. The knife advancement is improved by vertical vibration. Arm 6 is in this case fastened with a chain 7 from the the arm fixing part 10 to head 4. Thus it is possible to facilitate at least the arm advancement with a working-machine by pushing the arm forward.
Figure 3 shows a cross-section of arm 1, whereat its knifelike form becomes visible. The arm must be thin and still endure the forces which are transmitted through it to the head section. Also other profiles with a sharp front edge can come into question. The profile can also be hollow, whereat it is possible to take through it equipment necessary in certain situations, such as electric cables, force-pipes or pressure water to reduce friction if the soil is too dry. With force-pipes it is possible to arrange for instance in front of the head cone 4 a hydraulically rotatable cone worm to crush the soil, which is to be displaced, in order to facilitate the forward travel.
Figure 4 shows a cross-section of a hollow arm 12, in the space 13 of which pipes can be led to and back from the drilling head. By means of pipes it is even possible to convey up soil from the front of the advancing tube line.
The invention is not restricted to the enclosed embodiments but many modifications are possible within the limits of the invent- ional consept presented in the patent claims.