AU5753898A

AU5753898A - Process for emptying hoses filled with viscous masses

Info

Publication number: AU5753898A
Application number: AU57538/98A
Authority: AU
Inventors: Klemens Mathauer; Bernd Meyer-Roscher
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 1996-12-10
Filing date: 1997-12-04
Publication date: 1998-07-03
Also published as: EP0944527A1; JP2001505854A; WO1998025827A1; ID21854A; CN1245466A; CA2274542A1; DE19651267A1; TW380111B

Description

as originally filed 5 Method for emptying flexible tubes filled with pasty compositions 10 The invention relates to a method for emptying flexible tubes filled with pasty compositions and to an apparatus for carrying out this method. Pasty compositions such as for example sealing compositions, are often transported to wherever they are to be used in containers, such as for example drums. However, 15 these drums have the great disadvantage that they usually cannot be emptied in such a way that no remains of the compositions originally contained therein remain behind, which results in undesired residual soiling. This effect occurs in particular if the pasty compositions are very viscous materials. Of course, it is possible to fill the container again with the same material. However, it is found in practice that, for example in the 20 case of contact adhesives, the same container can be filled only two or three times. After that, the contaminants of the drum have an adverse effect on the properties of the product. The consequence is that the containers used either have to be cleaned with great effort or else disposed of. This results in a considerable volume of refuse and in high costs. 25 An alternative for the transportation of pasty compositions is represented by tubular casings. This form of transportation and selling is most well-known from the sector of sausage casings. DE-U 29 518 071 discloses a device for the apportioned filling of pasty product, in particular for filling tubular casings with sausage meat, which 30 device has as a conveying member for advancing the product to be filled, i.e. the sausage meat, a rotary slide driven in a housing.

2 DE-A 43 35 577 discloses a method and a device for producing, filling and closing bags made of an endless plastics film web. DE-A 44 12 697 describes a method and a device for checking the filling operation 5 when filling packaging casings, the filling apparatus being switched off in the absence of the packaging casing by a pulse generator in contact with the packaging casing. As uncomplicated as the transporting and handling of flexible tubes filled in this way 10 is, all the more difficult it is to empty them. The problem is evident in an analogous way from a toothpaste tube. This tube can admittedly be completely emptied by pressure exerted from the rear, closed end of the tube in the direction of the opening. However, the longer such a tube is, the less possible it is to bring about a discharge of product at one end by building up pressure at the other end. In particular in the case 15 of endless flexible tubes, the pressure to be exerted would have to be so great that it would cause any plastic film to burst. It is therefore an object of the present invention to provide a method for emptying flexible tubes filled with pasty compositions and an apparatus for carrying out this 20 method which are capable of making it possible to empty the flexible tubes continuously and largely completely. This object is achieved by a method for emptying flexible tubes filled with pasty compositions, comprising the steps of a flexible tube with a pasty composition being 25 clamped into an apparatus, comprising a tubular device, the flexible tube being passed through the tubular device, thereby opening the tubular casing along its length, and the opened tubular casing being separated from the pasty composition, and also the pasty composition leaving the apparatus via a discharge opening. 30 To achieve this object, there is also provided an apparatus for carrying out this method, comprising a tubular device having at least three openings, to be specific having at least one receiving opening for receiving filled flexible tubes, at least one 3 discharge opening and at least one further opening, one or more slitting-open devices being fitted between the at least one receiving opening and the at least one further opening. The further opening of the tubular device is in this case to be understood as meaning an opening which is off-set outwardly or laterally in its position in relation 5 to the - not necessarily straight - joining line between the center points of the two other openings. Thus, this opening does not necessarily face toward the side, but may also face upward or downward, taking the tubular device as a basis, thus in any spatial directions, as is explained in more detail below (cf. figure); nevertheless, hereafter this further opening is also referred to as a "lateral opening". 10 In the case of the method according to the invention, used for receiving the flexible tubes is a tubular device of which the diameter is dimensioned such that it is at least as large as that of the filled flexible tube to be received. The diameter of the tubular device - hereafter also referred to as a "tube", even though this does not necessarily 15 mean that it is a straight tube of uniformly round cross-section - is at least that much larger than that of the filled flexible tube to be received that the flexible tube can be made to pass through the tubular device by an exertion of force which lies below the limit value which causes the flexible tube to burst when it is passed through the tubular device. On the other hand, the ratio of diameter to length of the tubular device 20 is to be dimensioned such that the pressure building up during emptying of the flexible tube is able to dissipate over the length of the tubular device. In particular, the diameter and length of the tubular device are to be dimensioned such that back pressure of composition in the flexible tube is prevented. It is impossible to specify the exact numerical values for this in absolute dimensional units, since it also 25 depends on the type of pasty composition which is in the flexible tubes. In addition, these values also depend in a specific case on the structural design of the device used for the method according to the invention. For example, in the case of a tube arranged vertically for receiving the flexible tubes filled with pasty compositions, the value for the minimum or maximum diameter is different than if the tube or tubular device is 30 arranged in an oblique position or even horizontally, to make it easier to fill. The respective values for the desired diameters can, however, easily be determined by a person skilled in the art - under certain circumstances by means of just a few trial 4 tests. In the case of the method according to the invention, the flexible tube is opened by means of a slitting-open device, in particular a device similar to a blade, spike or 5 cutting roller, which is fitted between the receiving opening and the further or lateral opening of the tube. There may also be, however, two slitting-open devices, which are fitted opposite each other. In this case, the tubular casing is divided into two halves when opened. These halves can then be removed as planar films or sheets also via two opposite further openings of the device. Such an embodiment is preferred to 10 the extent that the emptying of the flexible tubes then proceeds in a way less susceptible to difficulties in problematical cases. The tubular casing itself is separated from the pasty composition in the tubular device, at the at least one further opening. For this purpose, in the further opening 15 there may be a pushing-out means and/or at least one stripping off device. The pushing-out means assists the separating of the pasty composition from the tubular casing opened along its length. Owing to the consistency of the pasty composition, it is preferred to use additionally a stripping-off device, which is located at the further opening. The stripping-off device may be a possibly adjustable separate device, such 20 as a stripping blade. The stripping-off device may, however, also be the correspondingly structurally modified edge of the further opening. Where possible because of the consistency of the pasty composition, in a preferred case the further opening may be a slit. The slit makes it easier for the opened tubular casing to be able to leave the tubular device already as a planar film. Thus, if during separation of the 25 pasty composition the tubular casing is passed via the pushing-out means and through the further opening, for instance through a slit, a planar film is obtained, which subsequently can be wound up for easier disposal. The wound-up roll subsequently contains the flexible tube in compressed form, which can be disposed of easily on account of the reduced volume. 30 In the case of the apparatus for carrying out the method according to the invention, part of the tubular device in the region between the slitting-open device and the 5 stripping-off device may also comprise a jacket-heated tube or housing. This makes it possible to control the temperature of the pasty composition and consequently, for example, also to influence its consistency, such as for instance the viscosity. Consequently, in this way as well, controlling the method is possible to a certain 5 extent. In addition, for this purpose, the blade itself may also be heated. The method according to the invention and the apparatus according to the invention are explained in more detail with reference to an example by the attached drawing: 10 The filled flexible tube [drawn here as a wound-up spiral (E)] is first of all passed through a tube (A). Shortly before the discharge opening or emptying point (B), which in this example is designed in the form of a downwardly open housing or tube, a spike or a knife is let into the guiding tube (A) from below. With the aid of this spike, the flexible tube, which is drawn over it, is slit open along its length. 15 Furthermore, the tube (A) has the task of preventing back pressure of product in the direction of the flexible-tube spiral (E). This is accomplished by the tube (A) being dimensioned such that it runs relatively closely around the flexible tube, but still leaves enough free space for the flexible tube to be able to be drawn through without 20 excessive resistance. Furthermore, the length of the tube (A) must be dimensioned such that the pressure made to build up by the emptying cannot be relieved at the tube end, which would entail an expansion or bursting of the flexible tube. Rather, the pressure must be dissipated over the length of the tubular device. 25 Once the flexible tube has been slit open by the spike, the tubular film is passed around a deflecting roller (C) in such a way that it can be wound up on a second roller (D). At the same time, the part of the filled product which does not flow of its own accord in the direction of the emptying opening (discharge opening), on account of the viscosity and gravity, is stripped off with the aid of a stripping-off blade, the 30 distance of which from the deflecting roller is variable. In the drawing the following means: 6 (A) tube (B) emplying point (C) deflecting roller 5 (D) second roller (E) flexible-tube spiral (F) blade or spike (G) stripping blade (H) tubular casing

Claims

1. A method of emptying flexible tubes filled with pasty compositions, 5 comprising the steps of - a flexible tube with a pasty composition being clamped into an apparatus, comprising a tubular device, - the flexible tube being passed through the tubular device, thereby 10 opening the tubular casing along its length, and - the opened tubular casing being separated from the pasty composition, and also - the pasty composition leaving the apparatus via a discharge opening. 15

2. The method as claimed in claim 1, the tubular casing separated from the pasty composition being wound up.

3. The method as claimed in one of claims 1 or 2, the tubular device having a diameter which is dimensioned such that it is at least as large as that of the 20 filled flexible tube to be received, with the proviso that it is at least that much larger than that of the filled flexible tube to be received that the flexible tube can be made to pass through the tubular device by an exertion of force which is below the limit value which causes the flexible tube to burst when it is passed through the tubular device. 25

4. The method as claimed in one of claims 1 to 3, the ratio of diameter to length of the tubular device being dimensioned such that the pressure building up during emptying of the flexible tube is able to dissipate over the length of the tubular device. 30

5. The method as claimed in one of claims 1 to 4, the flexible tube being opened by means of a slitting-open device, in particular a device similar to a blade or 8 spike.

6. The method as claimed in one of claims 1 to 5, the tubular casing being separated from the pasty composition in the tubular device. 5

7. The method as claimed in claim 6, in place of the separation there being at least one pushing-out means and at least one stripping-off device.

8. The method as claimed in claim 6 or 7, the emptied tubular casing being 10 passed via the at least one pushing-out means in such a way that it can subsequently be wound up as a film.

9. Apparatus for carrying out the method as claimed in one of claims 1 to 8, comprising a tubular device (A) having at least three openings, to be specific 15 having at least one receiving opening for receiving filled flexible tubes (E), at least one discharge opening and at least one further opening, one or more slitting-open devices (F) being fitted between the at least one receiving opening and the at least one further opening. 20

10. Apparatus as claimed in claim 9, at the at least one further opening there being at least one pushing-out means and at least one stripping-off device (G).

11. Apparatus as claimed in claim 9 or 10, the tubular device (A) being 25 dimensioned such that its diameter is at least as large as that of the filled flexible tube (E) to be received, with the proviso that it is that much larger than that of the filled flexible tube (E) to be received that the flexible tube (E) can be made to pass through the tubular device (A) by an exertion of force which is below the limit value which causes the flexible tube (E) to burst 30 when it is passed through the tubular device (A).

12. Apparatus as claimed in claims 9 to 11, the ratio of diameter to length of the 9 tubular device being dimensioned such that the pressure building up during emptying of the flexible tube (E) is able to dissipate over the length of the tubular device. (A) 5

13. Apparatus as claimed in claims 9 to 12, the part of the tubular device (A) between the slitting-open device (F) and the stripping-off device being a jacket-heated tube or housing.