EP3020485A1 - Pigging system - Google Patents

Abstract

A pigging system (1) for transporting liquid or pasty substances, in particular paints, comprises in a known manner two pig stations (3, 4) each having a pig channel which can receive a pig (13) in a parked position in which it abuts against a stop. The two pig channels are connected by a pig pipe (2). A pig changing device (8) is arranged within the movement path of the pig (13) between the two stops and comprises a movable element (31) having at least two receptacles (12) for a pig (13), which is optionally in the path of movement of the pig (13) between the two stops or in a path of movement of the pig (13) can be brought over which the pig (13) from the pig system (1) is removable.

Description

1. a) einer ersten Molchstation, die einen Molchkanal besitzt, der einen Molch in einer Parkposition aufnehmen kann, in der er an einem ersten Anschlag anliegt;
2. b) einer zweiten Molchstation, die ebenfalls einen Molchkanal besitzt, der einen Molch in einer Parkposition aufnehmen kann, in der er an einem zweiten Anschlag anliegt;
3. c) einer Molchleitung, die den Molchkanal der ersten Molchstation mit dem Molchkanal der zweiten Molchstation verbindet;
4. d) einer Molchwechseleinrichtung, mit welcher ein in dem Molchsystem befindlicher Molch gegen einen anderen Molch ausgetauscht werden kann.

The invention relates to a pigging system for transporting liquid or pasty substances, in particular paints, with

1. a) a first pig station having a pig channel, which can receive a pig in a parked position in which it rests against a first stop;
2. b) a second pig station, which also has a pig channel, which can receive a pig in a parked position in which it rests against a second stop;
3. c) a pig pipe which connects the pig channel of the first pig station with the pig channel of the second pig station;
4. d) a pig changing device with which a pig located in the pigging system can be exchanged for another pig.

Pigging systems for transporting liquid or pasty substances are widely used in industry, but especially in painting technology, where they are primarily used in supply units for application devices. There they are used, inter alia, for the transport of paint between paint-carrying ring lines of the spray booth and the application device.

Newts are subject to natural wear, causing them to leak after a period of operation and leak along them. They must then be replaced. This should be possible in the shortest possible time and possibly also automatically, so that expensive downtimes of the system are avoided as far as possible. In the pigging system used in the DE 10 2004 037 247 B4 is described and corresponds to the type mentioned, a pig exchange station is provided, which is located outside the path of movement of the pig between the two stops in the two pig stations and contains a variety of positions in which newts, new or defective, can be stored. This external pig change station is connected via a line or a hose to the pig station. Normally, the pig channel in this pig station is closed by a plug on which the pig moving in the pig system finds a stop. This plug is thus one of the two stops of the pigging system. To replace this pig, this plug is removed by a corresponding mechanism and leading to the pig change station hose is brought into communication with the pig channel, so that now the broken pig can be moved out and transported to a position of the pig change station. A new, functioning pig is then introduced in the opposite direction in the pig channel of the pig station and the pig channel is closed again by the stopper. In this way, a lot of pigs can be introduced into the pigging system, which ensures very long service lives. However, this mechanism is quite complicated and the times required for pigging are not insignificant.

Object of the present invention is to provide a pigging system of the type mentioned, with a worn or otherwise broken pig can be replaced in a very short time and with little equipment expense by another pig.

• e) die Molchwechselstation
  • ea) innerhalb des Bewegungsweges des Molches zwischen den beiden Anschlägen angeordnet ist;
  • eb) ein bewegliches Element aufweist, das mindestens zwei Aufnahmen für einen Molch aufweist, die wahlweise in den Bewegungsweg des Molches zwischen den beiden Anschlägen oder in einem Bewegungsweg des Molches gebracht werden können, über den der Molch aus dem Molchsystem entfernbar ist.

This object is achieved in that

• e) the pig exchange station
  • ea) is disposed within the path of movement of the pig between the two stops;
  • eb) has a movable member having at least two receptacles for a pig, which can be placed either in the path of movement of the pig between the two stops or in a path of movement of the pig over which the pig is removable from the pigging system.

According to the invention, therefore, the pig changing device is not provided outside the "normal" movement path of the pig between the two stops, as in the above-mentioned DE 10 2004 037 247 B4 the case is and where to replace the pig first a sealing plug must be removed and then replaced. Instead, the replacement of the pig within the path of movement between the two stops, so that a removal of a stop is not required. Due to the design of the movable element of the pig exchange device with two pig scans, it is possible to a pig from the between remove the two attacks lying, the transport of the liquid or pasty substance serving movement path and instead introduce into another path of movement, over which the pig can be removed. In this movement, so two pig shots exchange their place. It is possible to introduce a new pig into the "normal" path of movement simultaneously with the removal of a defective pig. These processes can be handled very quickly and automatically. The expenditure on equipment is comparatively low.

In one embodiment of the invention, the pig exchange device is arranged within the pig pipe and has at least one sensor that signals the presence of a pig, such that the pig can be stopped in the pig changing device. The function of this embodiment is thus such that the central control of the pigging system stops the supply of the pushing medium, which carries the pig through the pig pipe, and stops the pig in the pig station when the corresponding sensor emits a signal. Then the movable element of the pig station can come into operation. This embodiment of the invention is particularly suitable for retrofitting existing pigging systems.

Alternatively, the pig changer may also be housed in a pig station. This facilitates the pig-changing operation, because in the pig station the pig comes to a halt anyway at the end of its movement. This stop can then be used if necessary to change the pig by activating the pig changer. The inclusion of the pig changing device, which lies in the "normal" path of movement of the pig, thereby forming part of the pig channel of questionable pig station.

It is expedient if the stop of the pig connected to the pig station in question is arranged at the end of the reception of the pig changing device. Thus, at this end of its path of movement, the pig no longer emerges from receiving the pig changing device.

The movable element of the pig changer can be linearly displaceable.

In many cases, however, it is better if the movable element of the pig changer is formed similar to the drum of a drum turret and rotatable about an axis which is parallel to the axis of the receptacle. In this way, a larger number of receptacles for pigs can be accommodated in the pig changer without the space required increases too much. In addition, rotational movements are easier to achieve than linear movements.

Figur 1

schematisch ein erstes Ausführungsbeispiel eines Molchsystemes mit einer Molchwechseleinrichtung;

Figur 2

ebenso schematisch im Schnitt einen Ausschnitt aus einem zweiten Ausführungsbeispiel eines Molchsystemes mit Molchwechseleinrichtung;

Figur 3

die Seitenansicht eines eines trommelähnlichen beweglichen Elementes, wie es in der Molchwechseleinrichtung der Figur 2 verwendet werden kann;

Figur 4

eine Seitenansicht, ähnlich der Figur 3, eines alternativen Ausführungsbeispieles eines beweglichen Elementes für die Molchwechseleinrichtung der Figur 2.

Embodiments of the invention will be explained in more detail with reference to the drawing; show it

FIG. 1

schematically a first embodiment of a pigging system with a pig changing device;

FIG. 2

also schematically in section a section of a second embodiment of a pigging system with pig changing device;

FIG. 3

the side view of a drum-like movable element, as in the pig changing device of the FIG. 2 can be used;

FIG. 4

a side view similar to the one FIG. 3 , an alternative embodiment of a movable element for the pigging device of FIG. 2 ,

First, it will open FIG. 1 Reference is made, in which - in part schematically - an entire pigging system is shown, as it can be used to supply the paint of a high-rotation atomizer. The pigging system is designated overall by the reference numeral 1. It comprises, in a manner known per se, a first pig station 3, a second pig station 4, and a pig pipe 2 connecting the two pig stations 3, 4, which is subdivided into two sections 2a and 2b for reasons which will become clearer below.

The in FIG. 1 left pig station 3 is preceded by a color changer 5, the different media, in particular different colors of ring lines that can be supplied to the spray booth 3. From there, the selected medium can then with the help of a pig 13 via the pig pipe 2 to in FIG. 1 right pig station 4 are transported. From the pig station 4, the conveyed medium passes first into a metering device 6 and from there to a high-speed sprayer 7 delivering the paint to a workpiece. The two pig stations 3 and 4, the color changer 5, the metering device 6 and the high-rotation atomizer 7 can be of any known construction have. This also applies to the pig pipe 2, except that it is divided into two sections 2a and 2b.

The reason for the subdivision of the pig pipe 2 in said sections 2a, 2b is that between the sections 2a and 2b, a pig changing device, indicated generally by the reference numeral 8 is inserted, which will be described in more detail below.

The pig changing device 8 is similar in construction to the drum of a revolving drum. It comprises a movable element 31 with a hub part 9, which is rotatable about a dash-dotted line indicated axis 10 by motor. The hub part 9 is connected via radially extending connecting pieces 11 with short, parallel to each other and to the axis 10 extending pipe sections 12 in connection whose inner diameter corresponds to the inner diameter of the pig pipe 2 and which can each serve as a receptacle for a pig 13. At least two such pipe sections 12 are provided.

In normal operation of the pigging system 1, the ends of the sections 2 a, 2 b of the pig pipe 2 are at the opposite ends of one of the pipe sections 12, as in FIG. 1 is shown. In this figure, a pig 13 is shown, which is about to pass a pipe section 12 on the way between the two pig stations 3, 4, for example, from left to right. In the "normal operation" already mentioned, this pig 13 thus traverses, on the way from left to right in FIG. 1, the section 2a of the pig pipe 2, the pipe section 12 and then the section 2b of the pig pipe 2, first the section 2b of the pig pipe 2 on the return path , the pipe section 12 and the section 2a of the pig pipe 2. The function of in FIG. 1 Thus, pig system 1 shown so far differs in any way from that of known pigging systems.

The lower tube section 12 of the pig changer 8 can be from one side, in FIG. 1 From the left, pressurize via a nozzle 32 with a sliding medium, so that a pig 13 located in this pipe section 12 from the pipe section 12 to the other end, in the example to the right, can be expelled.

The pig 13 has a known construction. He is waisted in the middle, so that in both end regions respectively on the inner circumferential surface of the pig pipe 2 and the pipe section 12 adjacent sealing lips arise. On a front side of the pig 13 is provided with a projection 13a, whose function is initially irrelevant here.

In the region of the pig changing device 8, namely in the vicinity of the upper tube section 12, there are two sensors 30 which are able to signal the presence of a pig 13 in the upper tube section 12.

• Sind die Dichtlippen des Molches 13 nach einiger Zeit des "Normalbetriebes" verschlissen, so dass entlang des Molches 13 Leckagen auftreten, wird dieser gegen einen neuen Molch 13 ausgetauscht. Hierzu wird zunächst der neue Molch 13 über eine Molchleitung 33 in den unteren Rohrabschnitt 12 eingefahren. Der auszutauschende Molch 13 wird in den oberen Rohrabschnitt 12 gebracht. Sobald seine Anwesenheit dort von einem der Sensoren 30 festgestellt wird, wird die Zufuhr von Schiebemedium eingestellt, sodass der Molch 13 in dem oberen Rohrabschnitt 12 anhält.

The pig changer 8 described operates as follows:

• If the sealing lips of the pig 13 are worn after some time of "normal operation", so that leaks occur along the pig 13, it is exchanged for a new pig 13. For this purpose, the new pig 13 is first retracted via a pig pipe 33 into the lower pipe section 12. The pig 13 to be exchanged is brought into the upper pipe section 12. As soon as its presence is detected there by one of the sensors 30, the supply of pushing medium is stopped, so that the pig 13 stops in the upper pipe section 12.

Now, the movable member 31 of the pig exchanger 8 is rotated about the axis 10 by such an angle that the pipe provided with the new pig 13 12 inserted between the two pig pipe sections 2a and 2b and the worn pig 13 containing pipe section 12 between the nozzle 32nd and the end of the pig pipe 33 comes to rest. If only two pipe sections 12 are used, which are diametrically opposed, this angle is 180 °. The "normal operation" of the pig system 1 can again be resumed. For this purpose, the new pig 13 is driven from the pig changing device 8 in the pig station 3, where it can then be used again to transport the respective desired medium.

By contrast, the worn pig 13 located in the lower pipe section 12 is "shot out" into the pig pipe 33 and disposed of there or placed in a magazine.

The pig change described is not limited to cases in which the pig 13 is worn and must be replaced by a new one. A pig change is also conceivable when a color change has taken place. Then, a pig can be provided for each color in a connected pig magazine, which is introduced if necessary by means of pig exchange device 8 in the pig line 2.

FIG. 2 shows a section of an alternative pigging system. Parts corresponding to those of the embodiment of FIG. 1 are denoted by the same reference numeral plus 100.

In FIG. 2 the color changer 105, the pig station 103, the left end of the pig line 102 and a pig changer 108 can be seen. While in the embodiment of FIG. 1 the pig changing device 8 was arranged at an arbitrary position in the pig pipe 2, the pig changer 108 is in the embodiment of the FIG. 2 within a corresponding cavity in the housing 103a of the pig station 103. The movable element 131 of the pig exchange station 108 is designed as a disc which is rotatable about an axis 110 by motor. The axis 110 is again shown only schematically by a dash-dotted line.

The pig changer 108 is thereby formed similar to a drum of a revolver drum that it has a plurality of circular cylindrical bores 112 parallel to each other and to the rotation axis 110, which function in the interiors of the pipe sections 12 in the embodiment of FIG. 1 similar, so can serve as recordings for newts 113. The rotational position of the disk-shaped movable element 131 is such that in "normal operation" one of the bores 112 is coaxial with the end of the pig pipe 102 inserted into the housing 103a of the pig station 103 and communicates with this end via a cavity 125 in the housing 103a of the pig station 103 , In this way, a pig 113, which enters via the pig 102 into the pig station 103, get into the interior of the bore 112, as in FIG. 2 is shown. The cavity 125 serves in this way together with the upper bore 112 as a pig channel of the pig station 103rd

The holes 112 are not through holes. Rather, they have at the end of which the pig 102nd facing away, a radially inwardly projecting stop 112a, as in particular the FIG. 3 can be seen. This stop 112a ensures that the movement of the pig 113 in FIG. 2 to the left, so away from the pig 102, by abutting the projection 113 a of the pig 113 at this stop 112 a finds its end.

The stop 112a, as well as the FIG. 3 can be seen, a small through hole 112 b, which is coaxial with the bore 112.

A relatively narrow nozzle 120 is brought close to the through hole 112b of the stopper 112a. A through-bore 122 with a slightly larger cross section than that of the bore of the nozzle 120 passes through the body of the nozzle 120 parallel to the axis of the media channel 121 and thus the bore of the nozzle Nozzle 120.

In the FIG. 2 underlying hole 112 of the pig exchanger 108 communicates at its in FIG. 2 right side with a channel 123 in the housing 103a of the pig station 103, to which a further, leading to a pig change magazine or the like pig pipe can be connected.

Another, to in FIG. 2 lower bore 112 and channel 123 coaxial, narrow channel 124 in the housing 103 a is used to supply a push medium, as will become more apparent below.

Finally, in the FIG. 2 upper area of the pig station 103 a controllable connection 124 can be seen, via which a medium can be entered if necessary in the cavity 125 within the housing 103 a of the pig station 103. This cavity 125 bridges, like the FIG. 2 can be seen, in the upper region, the movable member 131 of the pig exchanger 108th

• Im Normalbetrieb, in dem Farbe aus dem Farbwechsler 105 zu der nicht dargesstellten, der Applikationseinrichtung benachbarten Molchstation befördert werden soll, befindet sich der Molch 113 zunächst, wie dies in Figur 2 gezeigt ist, in der oberen Bohrung 112 der Molchwechseleinrichtung 108 in Anlage an dem Anschlag 112a. Diese Position stellt ein Ende des Bewegungsweges des Molches 113 dar.

The function of in FIG. 2 Pigging system 101 shown is as follows, which is assumed by way of example that the pig 113 is pushed by the color, so the color itself serves as a pushing medium and no separate shift medium is used:

• In normal operation, in which color from the color changer 105 is to be conveyed to the unrepresented, the application device adjacent pig station, the pig 113 is initially, as shown in FIG. 2 is shown in the upper bore 112 of the pig exchanger 108 in abutment against the stop 112a. This position represents an end of the movement path of the pig 113.

Now, the pig 113 can be set in motion, that on the media channel 121 of the color changer 105, the nozzle channel of the nozzle 120 and the through hole 122 color under pressure on the in FIG. 2 left end face of the pig 113 is given. Appropriate coordination of the cross sections of the nozzle channel of the nozzle 120 and the through hole 120 is achieved that the pig 113 is first pushed out of the bore 112 of the pig exchanger 108 out into the pig 102, before then the color also follows through the through hole 122. The paint now pushes the pig 113 through the pig pipe to the not shown further pig station at the other end of the pig 102nd

The second pig station is designed in a conventional manner. The removal of the paint thus takes place there, as is known from the prior art. The same applies to the return of the pig 113 from the second pig station in the opposite direction through the pig pipe 102 until the pig 113 is again in the in FIG. 2 shown position within the upper bore 112 of the pig changer 108 has arrived.

• Wie der Figur 2 zu entnehmen ist, befindet sich in der unteren Bohrung 112 bereits ein neuer, funktionstüchtiger Molch 113, der dieser Bohrung 112 über die an den Kanal 123 angeschlossene Molchleitung zugeführt wurde. Nunmehr wird das bewegliche Element 131 der Molchwechseleinrichtung 108 um die Achse 110 verdreht. Nimmt man an, dass die Molchwechseleinrichtung 108 in der Seitenansicht so aussieht, wie dies in Figur 3 dargestellt ist, die Molchwechseleinrichtung 108 also nur zwei diametral gegenüberliegende Bohrungen 112 besitzt, so findet eine Drehung der Molchwechseleinrichtung 108 um 180° statt. Bei dieser Drehung gelangt der zunächst untere, neue Molch 113 in Fluchtung mit der Molchleitung 102, während der verbrauchte, auszutauschende Molch 113 in Fluchtung mit dem Molchkanal 123 kommt. Nunmehr kann bereits der "Normalbetrieb" unter Verwendung des ausgetauschten Molches 113 erfolgen.

If the pig 113 has worn out after a certain period of operation and has therefore become leaky, it is replaced in the following way:

• Again FIG. 2 can be seen, is located in the lower bore 112 already a new, working pig 113, which was supplied to this bore 112 via the connected to the channel 123 pig pipe. Now, the movable member 131 of the pig exchanger 108 is rotated about the axis 110. Assuming that the pig changer 108 in the side view looks like this FIG. 3 is shown, the pig exchange device 108 thus has only two diametrically opposite holes 112, so there is a rotation of the pig changer 108 by 180 °. During this rotation, the initially lower, new pig 113 comes into alignment with the pig pipe 102, while the used pig 113 to be exchanged comes into alignment with the pig channel 123. Now, the "normal operation" can already be done using the exchanged pig 113.

The broken newt in the in FIG. 2 Lower bore 112 is via sliding medium, which is the channel 124 in the housing 103 a of the pig station 103, in the channel 123 and then ejected via the connected pig pipe in the pig magazine, not shown.

Similarly, the pig 113 can be replaced if a color change is to be made without the pig 113 therefore being worn.

The number of receptacles for pigs in the respective movable element 31 or 131 of the pig change station 8 and 108 may of course be greater than two. In FIG. 4 an example is shown in side view, in which four receptacles 212 are provided for pigs.

In one embodiment, not shown, can be dispensed with the separate stop 112a in the movable member 131. The end face of the nozzle 120 acts in this case as a stop for the pig 113, the projection 113a is advantageously provided with a flat end face.

With the pig change does not necessarily wait until a pig defect is detected. A pig change can also be made as a precaution after a certain number of pig movement cycles.

Finally, if necessary via the pig changing device instead of a pig and a Inspektionsintrument be introduced into the pigging system, which certain detection devices, eg. B. a camera, leads to the examination of the line system with it.

Claims (6)

Pigging system for transporting liquid or pasty substances, in particular paints, with a) a first pig station (3; 103) having a pig channel (112, 125) capable of receiving a pig (13; 113) in a parked position abutting against a first stop (112a); b) a second pig station (4), which also has a pig channel, which can receive a pig (13; 113) in a parking position in which it rests against a second stop; c) a pig pipe (2, 102) which connects the pig channel (112, 125) of the first pig station (3, 103) with the pig channel of the second pig station (4); d) a pig changing device (8; 108) with which a pig (13; 113) located in the pigging system (1; 101) can be exchanged for another pig (13; 113); characterized in that e) the pig changing device (8; 108) ea) is disposed within the path of movement of the pig (13; 113) between the two stops (112a); eb) has a movable element (31; 131) which has at least two receptacles (12; 112) for a pig (13; 113) which can be inserted in the path of movement of the pig (13; 113) between the two stops (112a) or can be brought into a path of movement of the pig (13, 113), over which the pig (13, 113) from the pig system (1, 101) is removable. Pigging system according to claim 1, characterized
in that the pig changing device (8) is arranged inside the pig pipe (2) and has at least one sensor (30) which signals the presence of a pig (13), such that the pig (13) can be stopped in the pig changing device (8). Pigging system according to claim 1, characterized
that the pig change means (108) is housed in a pig station (103). Pigging system according to claim 3, characterized
in that a stop (112a) for the pig (113) is arranged at the end of the receptacle (112) of the pig changer (108). Pigging system according to one of the preceding claims,
characterized in that the movable element of the pig changer is linearly displaceable. Pigging system according to one of claims 1 to 4, characterized in that the movable element (31; 131) of the pig changing device (8; 108) similar The drum of a drum turret is formed and about an axis (10; 110) is rotatable, which is parallel to the axes of the receptacles (12; 112).

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