The present invention relates to a method that forms part of operations that are carried out for the purpose of unclogging and repairing a drilled-through drainpipe or sewage pipe.

Such a method is generally known. In the known method, the clogged drainpipe or sewage pipe is exposed by digging a hole in the ground, after which the pipe is opened by knocking a hole therein or sawing or drilling it through, after which the hole that has been dug, and in some cases also the area around the hole, is flooded with drainage or sewage water and the substances present

therein. Said substances not only contain bacteria and other germs, but in some cases also chemically very

aggressive substances used at an earlier stage by the occupants in an attempt to remove the blockage themselves. Subsequently, the blockage must be traced and removed while standing in the aforesaid hole flooded with contaminated and environmentally polluting drainage water, and in many cases one or more drainpipe sections or manifolds need to be replaced and be glued together. Before this is done, the contaminated drainage water is pumped out in order to be discharged elsewhere.

In the meantime there is a chance that the hole will gradually become filled with new drainage water again. If unclogging and repairing takes longer, temporary facilities must be provided or the occupants must be asked not to drain anything or as little as possible during that time, which is in some cases very problematic.

Add to the above drawbacks of the known method the contamination of the soil, the risk of infection with diseases or allergies and the odour nuisance, which may remain for a long time even after the hole has been filled up again. The object of the present invention is to provide a cleaner, safer and quicker method which does not exhibit the aforesaid drawbacks, or at least to a much lesser extent, and which reduces the dangers to which the

personnel involved is exposed and the nuisance to the surrounding area.

In order to accomplish that object, the method according to the invention is characterised in that a clogged drainpipe is provided with a watertight bottom section to be placed under the drainpipe, upstream of the clogged part thereof, on which bottom section at least one top section provided with a drill guide is placed, after which a hole is drilled in the drainpipe above the bottom section .

The advantage of the method according to the

invention is that the watertight bottom section functions as a collecting container after the clogged drainpipe has been drilled through, into which the contaminated drainage water running from the drainpipe can flow without

contaminating the surrounding area or the soil. The soil remains dry, it is not contaminated and the environment is burdened less, whilst in addition it obviates the need for a clean-up operation, which is sometimes necessary so as not to commit an offence against the environment. The method thus provides a possibility to comply with the latest environmental and safety regulations for personnel. In other words, the rules regarding personal protective equipment could be slackened somewhat without any adverse effects for the personnel involved.

The personnel moreover has a possibility to stand in the other part of the hole, without coming into contact with the drainage water, and remove the blockage in a more acceptable manner, usually by means of a high-pressure unblocking hose, via a hole that has been drilled in the drainpipe .

After this, or even at an earlier stage, at least the bottom section of the collecting container can be pumped out in practice, and the drainpipe, which has been

unclogged in the meantime, can be replaced or repaired.

The above-described method according to the invention can advantageously be used inter alia for houses, apartment buildings or office buildings.

One embodiment of the method according to the

invention is characterised in that the drainage water that is present in the bottom section is pumped out, which may or may not take place in response to a command from one or more level sensors.

Advantageous is the fact that the drainage water can be removed before or while the unclogging and repair method is carried out. If the method takes up a longer period of time, said pumping out can take place by means of a working pump, using a pumping line functioning as a temporary provision, which opens into the top section and/or the bottom section, until the job can be completed, usually the next day. The pump only needs to be activated occasionally if it is controlled by means of one or more level sensors which monitor the level of the drainage water in the collecting container and signal the control means to activate the pump when the level is too high. Another embodiment of the method according to the invention is characterised in that the bottom section and the top section are joined together in a watertight manner.

The advantage of this is that the top section can function as a temporary storage space for the drainage water that may have collected therein as well. The pump only needs to be activated for a shorter period of time in that case, so that the noise produced by the pump or by a generator that may be used will be less objectionable to the direct vicinity. In addition, virtually no stench will in that case emanate from the contaminated substance being contained in the hermetically sealed collecting container.

Further detailed possible embodiments defined in the other claims and their concomitant advantages are set forth in the description below.

The method and the collecting system according to the present invention will now be explained in more detail with reference to the figure below. The figure is a schematic view (not to scale) of possible embodiments of the

collecting system according to the invention, on the basis of which also the corresponding method will be explained.

The figure shows a collecting system 1 which is made up of a watertight collecting section 2 which can be stably placed in a hole in the ground, possibly using special means, in this case feet 3 (one of which is shown) , and which can be buried in the ground, if desired. As shown, the collecting section 2 comprises a passage or inlet 4, in which a clogged sewage or drainage pipe 6, for example from a house 5, can be received. The clogged part is located to the left of the collecting section 2, seen in the figure. The inlet 4 may be provided with a flexible sleeve and/or with clamping means 7 for clamping the drainpipe 6 down in the inlet 4 of the collecting section 2. In principle the collecting section 2 may at least in part be built up of several individual sections or partitions to be assembled into a stable unit, as is schematically shown.

The system 1 further comprises a top section 8 to be placed on top of the bottom section 2, which top section may consist of more than one part. Usually flexible sealing sections 2 are provided between the sections 2 and 8 that are to be clamped together so as to realise a sufficiently- watertight seal therebetween. In a possible variant (not shown) the inlet 4 is located in the boundary surface between the two sections 2 and 8. The drainpipe 6 can be simply laid on top of the collecting section 2 in that case, whilst the collecting section 2 is placed under the drainpipe 6. The collecting section 2 need not be built up of individual sections on site in that case.

The illustrated upper part of the top section 8 is provided with a drill guide 10 for guiding a drill or drill rod 11 to be inserted therein, by means of which a hole can be drilled in the drainpipe 6. The contaminated rainwater that has collected in the drainpipe 6 will initially gush into the collecting section 2 after a hole has been drilled in the drainpipe and collect therein, and possibly also in the top section 8. The illustrated upper part of the top section 8 is provided with a connection 12 for a suction pump, which pumps out the container consisting of the sections 2 and 8, which are joined together in a watertight manner, and which carries the substance to be discharged to a storage tank 14. The storage tank 14 may be a mobile storage tank which is placed on a vehicle.

To facilitate placing and moving the top section 8, the top section 8 is provided with handles 15. When used with larger systems 1, said section might also be provided with a crane hook.

The interior of the collecting section 2 and/or the top section 8 may be provided with water level sensors to be connected to a pump control unit, which sensors function to detect the water level and deliver a command to the pump 13 to suction water out of the container when said level is too high. The system may be provided with communication means (not shown) which, when connected to the sensors or to failure-detecting sensors, transmit status information via GSM or e-mail.