EP0022251B1 - Valve with a body connectible to tubes for conveying pressurized dense fluids, for instance concrete, for introducing a cleaning pig - Google Patents

Description

The invention relates to a pipeline fitting with a housing which can be installed in lines which convey pressurized thick materials, preferably concrete, for changing a wiper, preferably a ball, which is pressed through the line with a pressure medium.

The invention is explained below on the basis of its preferred field of application, although it is applicable not only to the cleaning of concrete delivery lines but also to other thick material conveying pipes which e.g. Can convey slurries of pulpy to sludge-like consistency, which solidify in the pipeline when the conveying movement stops for a long time. This is particularly unpleasant for concrete, because hardening concrete causes blockages in metal pipes that are practically no longer removable. Therefore, at the end of the concrete delivery, concrete delivery lines not only have to be emptied, but also wiped clean.

It is known to return the pipeline, which is usually attached to a concrete placing boom, by sucking back the concrete contained in the pipeline into the prefill container at the base of the pipeline, which usually interacts with the mast, with a wiper in the form of a Ball is introduced from an elastomeric material.

However, the method presupposes that the prefilling container has a sufficiently large volume to accommodate the concrete sucked back. On the one hand, because of the larger pipe diameter in modern concrete conveying systems, and on the other hand, because of the limited dimensions of the concrete pumps, which are particularly mounted on truck chassis, the prefilling container dimensions are often not sufficient. This leads to contamination of the components lying outside the prefilling container and their surroundings when the residual concrete is sucked back. In addition, the concrete that has been sucked back must be emptied from the prefill container. As a rule, there is no use for this at the end of concrete delivery; therefore concrete losses occur, which are considerable due to the large pipe diameter. In addition, the construction site is contaminated with the residual concrete because the excess concrete is usually deposited there.

It is also difficult to push the residual concrete through the pipeline in the opposite direction. Among other things, this is due to the pressure under which the concrete filling of the pipeline stands when the mast is erected. Most of the time, the conditions on the construction site do not allow the mast to be moved into a position that would be necessary to relieve the pressure on the delivery line. It is therefore sometimes helpful to install a gate valve and a pipe fitting with the characteristics described in the beginning in the concrete delivery line. This fitting has so far been located behind the gate valve and practically consists of a flange-mounted housing in which the prepared wiper is located. You can install the housing with the slider closed and press the wiper through the line after opening the slider. This method has the considerable advantage that the residual concrete can be conveyed into the formwork on the construction site and is therefore not lost. So far, however, it has had the major disadvantage that the installation and removal of the pipe fitting described requires too much time and too much technical effort (Iv Eckerdstein, pump concrete and concrete pumps, publisher: Friedrich Wilhelm Schwing GmbH, Baumschinenfabriken, D-4690 Herne 2, 5th edition, October 1976).

The invention has for its object to provide a pipeline fitting that can remain in the pipeline, the deportation is spared and can even be cleaned with the wiper.

According to the invention, this object is achieved by a mutually adjustable member which has a through-pipe which can be aligned with the pipeline and a pipe chamber made of a blind pipe which receives the wiper, the bottom of which has a connecting channel to the pressure medium connection arranged on the outside.

Due to the mutual adjustability, it is possible to use the through-pipe for concrete delivery with the fitting permanently installed in the pipeline and to change the wiper with the help of the pipe chamber, at the same time the pipeline is blocked off with the bottom of the blind pipe. In this operating state, only the pressure medium - pressurized water or compressed air - then needs to be cleared the way through the connecting channel. The wiper then pushes the remaining concrete out of the pipeline and wipes the pipes clean.

As soon as the line is empty, the organ can be switched over so that the through-pipe still filled with concrete is also emptied when the wiper is sucked back and the subsequent pipe section is emptied into the pre-filling container. Since the pipeline fitting according to the invention can be installed in the delivery line in the immediate vicinity of the prefilling container, the loss of this residual amount is irrelevant.

Preferably and according to a further feature of the invention, the mutually adjustable member is designed as a slide, in which the through tube and the blind tube are arranged axially parallel. Such a slide can be operated in a known manner by hand, but also with the aid of an adjusting motor.

According to the invention, the pressure medium connection is preferably provided with a T-piece, to which a pressure gauge and a venting or relief member can be connected.

According to the invention, it is possible through the mutual adjustability of the organ with the fitting permanently installed in the pipeline to use the through pipe for the conveying of concrete and to use the pipe chamber to wipe the wiper change, at the same time the pipeline is shut off with the bottom of the dummy pipe. In this operating state, only the pressure medium - pressurized water or compressed air - then needs to be cleared the way through the connecting channel. The wiper then pushes the remaining concrete out of the pipeline and wipes the pipes clean.

If cleaning is to be carried out at the end of the delivery, the slide must be actuated without the medium under pressure in the line being able to escape to the outside. This presupposes that both ends of the through tube in the valve housing are sealed on a plate, the tube ends sliding on the plates assigned to them during the changeover process. These seals require extensive housings and are problematic for technical and economic reasons. As a result, the housing must be installed in the delivery line as a separate structural unit behind a pump, for example a concrete pump. This prevents the delivery line from being easily connected to the pump.

As soon as the line is empty, you have to change the valve body so that the through-pipe still filled with concrete is also emptied when the wiper is sucked back, and the connecting pipe section is emptied into the pump's pre-fill tank. Since the valve cannot be installed directly behind the concrete pump, on the other hand the content of the pre-filling container, which is present in particular on mobile pumps, in particular concrete pumps, is limited, the concrete emerging when the wiper is sucked back must be accommodated in the pre-filling container and removed therefrom later. This leads to considerable difficulties when conveying concrete, because the concrete cannot be placed in the formwork. This concrete must be placed on the construction site or otherwise.

According to a further solution to the problem on which the invention is based, it is provided that a through-tube is designed as a curved swivel body, the outlet end of which is connected to the delivery line with a joint and the inlet end of which is movable on a plate which defines the opening for a tube chamber arranged behind the plate and for a tubular inlet of the delivery line, the tube chamber consisting of a wiper receiving blind tube, the bottom of which has a connecting channel to the pressure medium connection arranged on the outside.

This embodiment of the invention results in a simplified housing and the possibility of reducing the amount of residual concrete that has to be accommodated in the prefilling container.

Since the passage tube is kept in constant, albeit articulated, connection with the delivery line due to its design as a swivel body, no plate seal is required at the conveying end of the passage tube and the housing can therefore be simplified accordingly. Since the through pipe also serves to connect the pipe chamber to the delivery line, it is cleaned together with the delivery line in one operation. As a result, the residual flow rate which is removed from the conveying path when sucking back is reduced accordingly. As a result, the possibility is created of permanently installing the pipe fitting directly behind a pump, in particular a concrete pump, without having to interrupt the delivery line immediately before the pump, as was previously the case. The short distance of the pump pistons from the valve then enables the remaining amount of thick matter to be sucked off into the prefilling container, so that the entire conveying path is cleaned in a simple manner after the completion of the conveying.

According to the invention, a further simplification of the overall structure of a thick matter pump, in particular a concrete pump, on which the valve according to the invention is to be permanently installed, is achieved in that the swivel body connects the two alternately filling and delivering delivery cylinders of a piston pump, which form the tubular inlet, to the delivery line , wherein the plate for each feed cylinder and the tube chamber has recesses and is arranged on one side of the prefill container of the pump.

In this case, the housing of the switching element of the piston pump is used as the housing of the valve, whereby only a tube chamber is provided on the existing housing and the swivel body, which is already present in such a housing, is used as a through-tube because it cleans the housing during cleaning Pumping stops anyway.

For this reason, the through-tube of the fitting according to the invention can be given the designs customary in the case of such change-over members of piston pumps, in particular concrete pumps. It can therefore be bent in an S-shape, but can also be achieved with a simple pipe bend.

• Fig. 1 schematisch, d.h. unter Fortlassung aller für das Verständnis der Erfindung nicht erforderlichen Einzelheiten, im Längsschnitt eine Betonförderleitung mit eingebauter erfindungsgemässer Rohrleitungsarmatur, deren Organ sich in einer ersten Betriebsstellung befindet,
• Fig. 2 in der Fig. 1 entsprechender Darstellung eine weitere Betriebsstellung,
• Fig. 3 in den Fig. 1 und 2 entsprechender Darstellung das Reinigen der Rohrleitung mit Hilfe des Druckmittels,
• Fig. 4 die Betriebsstellung nach Fig. 1 am Ende der Reinigung,
• Fig. 5 den Vorbereitungsschritt zur Reinigung des wechselseitig verstellbaren Organs und des Reststückes der Förderleitung,
• Fig. 6 in den Fig. 1 bis 5 entsprechender Darstellung die Reinigung des Reststückes der Förderleitung,
• Fig. 7 in schematischer, perspektivischer Ansicht eine Betonpumpe mit integrierter Rohrleitungsarmatur gemäss der Erfindung,
• Fig. 8 in der Fig. 7 entsprechender Darstellung die Stellung der Teile beim Reinigen der Förderleitung,
• Fig. 9 im Schnitt und unter Fortlassung aller für das Verständnis der Erfindung nicht erforderlichen Einzelheiten eine andere Ausführungsform einer in die Teile einer Betonförderpumpe integrierten Rohrleitungsarmatur gemäss der Erfindung,
• Fig. 10 eine Draufsicht auf den Gegenstand der Fig. 9,
• Fig. 11 eine andere Ausführungsform der erfindungsgemässen Rohrleitungsarmatur, die an beliebiger Stelle in eine Förderleitung eingebaut werden kann, teilweise im Schnitt,
• Fig. 12 den Gegenstand der Fig. 11 in der anderen Betriebsstellung des Schwenkkörpers und
• Fig. 13 in den Fig. 11 und 12 entsprechender Darstellung die Reinigung des an die Rohrleitungsarmatur anschliessenden und bis zu der nicht dargestellten Pumpe reichenden Leitungsabschnittes.

For a better understanding, the invention is explained in more detail below with reference to several embodiments, which reflect the details of the invention, its further features and other advantages; show it:

• 1 schematically, ie omitting all details not necessary for understanding the invention, in longitudinal section a concrete delivery line with built-in pipe fitting according to the invention, the organ of which is in a first operating position,
• 2 corresponding representation of a further operating position,
• 3 in FIGS. 1 and 2 corresponding representation, the cleaning of the pipe using the pressure medium,
• 4 shows the operating position according to FIG. 1 at the end of cleaning,
• 5 shows the preparation step for cleaning the mutually adjustable organ and the remnant of the delivery line,
• 6 in FIGS. 1 to 5 corresponding representation, the cleaning of the remnant of the delivery line,
• 7 is a schematic, perspective view of a concrete pump with an integrated pipe fitting according to the invention,
• 8 corresponding representation of the position of the parts when cleaning the delivery line,
• 9 in section and omitting all details not necessary for understanding the invention, another embodiment of a pipeline fitting integrated into the parts of a concrete delivery pump according to the invention,
• 10 is a plan view of the subject of FIG. 9,
• 11 shows another embodiment of the pipeline fitting according to the invention, which can be installed anywhere in a delivery line, partly in section,
• Fig. 12 shows the subject of Fig. 11 in the other operating position of the swivel body and
• Fig. 13 in FIGS. 11 and 12 corresponding representation, the cleaning of the pipe section connecting to the pipe section and extending to the pump, not shown.

In the figures, 1 denotes a concrete delivery line which is carried, for example, by a concrete placing boom, not shown. At 2 and 3, a housing 4 is flanged, which belongs to the pipeline fitting generally designated 5. The housing 4 is installed in the line 1 in this way. The installation point is located just behind a prefill container, not shown, to which the pipe 6 leads.

The line has a mutually adjustable organ, which is generally designated 7. According to the illustrated embodiment, the organ consists of a structural unit that combines a through tube 8 and a tube chamber 9. For its part, as can be seen in particular in FIG. 3, the tube chamber consists of a blind tube 9 ', the bottom 10 of which is provided with a connecting channel (FIG. 2) which bears the reference number 11. The connecting channel has a section 12 which is arranged axially to the blind pipe 9 and a section 13 which is angled in relation thereto and which runs transversely to the axis of the delivery line 1 and accordingly leads outwards. On the outer end of the connecting channel 11 there is a T-piece 14 to which a connection 15 for a pressure medium, e.g. Pressurized water or compressed air is attached, and a manometer 16, which indicates the pressure generated by the pressure medium in the pipeline. A tap 17 enables the delivery line 1 to be emptied in the open state.

According to the exemplary embodiment shown, the organ 7 described is designed as a slide which can be adjusted in two operating positions in a plane orthogonal to the line axis. In the position shown in FIG. 1, the blind pipe 9 lies outside the housing 4. For this reason, the wiper, generally designated (19) at 19, can be inserted in the form of a ball into the tube chamber, which is formed by the blind pipe 9 '. In the same position, however, the through pipe 8 is aligned with the delivery line 1 and the connecting pipe 6. As a result, concrete 20 can be pressed from the prefilling container into line 1 and conveyed using the pump, not shown.

As soon as the funding has ended, the entire pipeline, including the mutually adjustable member, must be cleared of the concrete, which would otherwise harden and block the delivery routes. For this purpose, the organ is moved into the other operating position, which is shown in Fig. 2. In this position, the pipe chamber is aligned with the delivery line 1, but the through pipe 8 filled with concrete is located within the housing 4 and is therefore not yet freed from the concrete.

First, the delivery line 1 is emptied and wiped clean. For this purpose, with the aid of a pump 21, pressurized water is pressed into the pipe chamber via the connection channel 11 via the connection 15 according to the exemplary embodiment. As a result, the wiper 19 is moved in the direction indicated by the arrows 22 and presses the residual concrete in front of it, which emerges at the end of the conveying line 1 and can be introduced into the formwork which has previously been filled with the conveying concrete.

At the end of this emptying and cleaning process, the wiper 19 emerges from the pipeline.

Then you move the organ 7 back to its initial position shown in FIG. 1, which is shown in Fig. 4. So that the through pipe 8 with the concrete contained in it is aligned again with the delivery line 1 and the connecting pipe 6, but the pipe chamber 7 comes back into a position in which the wiper 19 can be inserted into the blind pipe.

After pressure water has been released again with the pump 21 into the blind pipe 9 via the connection 15, which is shown in FIG. 5, the wiper 19 moves again in the direction of the arrows 22. However, the wiper 19 is only required as far into the To press pipe 1 or in the housing 4 that the movement of the adjustable member 7 is released again.

After this has been done, the organ 7 is moved back into its second position, which is shown in FIG. 6. In this position, the concrete pump (not shown) is sucked through the pipe 6 into the wiper body 19, which then pushes the residual concrete still contained in the through pipe 8 and in the line 6 in the direction of the arrows 24 and finally conveys it into the prefilling container.

Deviating from the illustrated embodiment, compressed air can also be used instead of pressurized water. Then you have to watch the manometer 16 closely, however, because air is compressible in contrast to pressurized water and therefore the residual concrete can suddenly emerge from the delivery line 1.

For a better understanding, the invention is first explained on the basis of the design according to FIGS. 11-13. A delivery line 101 for concrete 102 is separated at 103, so that there is a line section, not shown, which leads to a concrete pump. A housing 104 of a pipeline fitting is installed at the separation point. The housing be is limited to those parts that are required to transmit the separation forces and to connect the two line sections of the concrete delivery line 101.

The housing then has a tubular inlet 105 for the incoming concrete, with which the housing can be flange-mounted, for example, on the concrete pump. The inlet pipe 105 sits on an end plate 106 of the housing 104, on which a pipe chamber 107 is also attached. The tube chamber is empty during the concrete delivery shown in FIG. 11 with the exception of a wiper 108, which has the shape of a ball in the exemplary embodiment shown. The tube chamber 107 has the shape of a blind tube and accordingly has a chamber base 109 which has a connection channel (not shown) to an external pressure medium connection, the function of which is explained below.

Between the parts 105 and 107 there is a pivot axis 110 for a through pipe 111, the end of which is facing the plate 106 and is sealed thereon with the aid of a seal shown schematically at 112 in such a way that concrete escapes in every operating position and in every intermediate position 102 to the outside is prevented. The pipe end 114 opposite the sealed pipe end 113 is seated in a pipe joint 115 and is also, as schematically indicated at 117, sealed to the outside. The pipe joint 117 is connected to the plate 106 of the housing with a tie rod 118. The tie rod also serves to support a preferably hydraulic actuating cylinder 120 mounted at 119, which can actuate the through tube via a lever 121 so that it pivots about the axis 110, its seal 112 moving on the plate 106. During this movement, the through tube 111 is rotated in the tubular joint 115 due to its design as an S-shaped curved swivel body, so that it remains in constant connection with the delivery line 101.

In operation, concrete 102 is continuously pressed through the tubular inlet 105, the S-shaped through tube 111 and the delivery line 101 with the aid of the concrete pump (not shown). At the end of the conveying, the concrete located in the delivery line 101 and the parts of the fitting adjoining it must be removed in order to avoid the blocking of the delivery routes due to the hardening of the concrete. For this purpose, by actuating the thrust piston transmission, which is realized with the hydraulic cylinder 120, the through-tube 111 can be moved into the position according to FIG. 12 after the cleaning ball 108 described has previously been inserted into the tube chamber 107. If the pressure medium connection, not shown, of the tube chamber 107 is opened, a hydraulic or pneumatic cleaning medium, as indicated by the arrows 122 in FIG. 12, presses the wiper 108 first through the through-pipe 111 and then through the delivery line 101. The wiper pushes here the concrete 102 in front of it, which therefore exits at the free end of the delivery line, where it can be housed in a formwork.

As a result of the open design of the housing 104, the same or a further wiper 128 can also be introduced into the tubular inlet of the fitting and, by switching the pump in the direction of the arrows 129, can be pressed into the prefilling container usually provided in such pumps. The entire conveying path is then free of concrete.

In the embodiment according to FIGS. 7 and 8, the valve described is integrated in the changeover element 130 of a concrete pump, generally designated 131. The concrete pump has two delivery cylinders 132, 133, each of which contains a piston which is actuated by working cylinders 134, 135. The conveying cylinders 132 and 133 work alternately in such a way that their pistons suck concrete when they return from a prefilling container 136, which is pressed into the conveying line 101 at the inlet. The changeover required for this takes place with the changeover element which is built into the prefilling container 136.

The changeover member 130 has a movable swivel body 137 in the form of an S-shaped tube. The end 138 of the pivot body sits in a tubular joint at 139, while the opposite, i.e. the cylinder-side tube end 140 slides on a plate 141 and is sealed thereon. With the help of a two-armed lever 142, the pipe end 140 can be pivoted via the piston rod 143 of a hydraulic cylinder 144 into three positions, which are designated 1-111 in FIG. 7. Items I and 11 apply to concrete delivery.

In the position of the parts shown in FIG. 7, the delivery cylinder 133 sucks concrete out of the prefilling container 136, while at the same time the delivery cylinder 132 presses the previously sucked-in concrete through the swivel body 137 into the delivery line 101. In position I, the feed cylinders 132, 133 are reversed.

In position 111, which is shown in FIG. 8, the thrust piston gear 143, 144 and the tube end 140 are aligned with the tube chamber shown at 146, which has a removable tube plate 149. The detachability of the tube plate makes it possible to insert the cleaning body 150 into the tube chamber 146 from the outside, so that the prefilling container 136 does not need to be emptied before the wiper 150 is inserted. Otherwise, the swivel body 137 and the subsequent delivery line 101 can be cleaned in the manner of operation described in connection with FIGS. 11-13 by supplying pressure medium according to the arrows 151 into the tube chamber 146.

The embodiment according to FIGS. 9 and 10 differs from the embodiment according to FIGS. 11-13 essentially by the design of the through tube. In the exemplary embodiment according to FIGS. 9 and 10, the through-pipe is designated 160 and is mounted with its end 161 in a pipe joint 162 which is sealed off at 163 and connects the end 161 to the delivery line 101. The housing is labeled 164 and again openly trained. It consists essentially of the angularly shaped anchors 165 and 166, and a curved plate 167, which carries the inlet 105 and the tube chamber 107. According to the configuration of the plate 167, the other end 168 of the through tube 160 is provided with a correspondingly curved flange 169 which is movable on the inside 170 of the plate 167. The housing also has connections 171, 172 for fastening to the substructure of a mobile concrete pump.

FIG. 9 shows the position of the parts during the conveying of concrete, in which the through pipe 160 is connected to the pipe inlet 105. 10 shows the parts in the position necessary for cleaning. Here, the through pipe 160 is aligned with the pipe chamber 107, pressure medium being supplied in accordance with the arrows 122, so that the wiper 108 can press the concrete in front of it, while the wiper 128 is sucked back into the prefilling container in accordance with the arrows 129.

Claims (7)

1. Pipe fitting with a housing (4, 104) which can be built into pipelines (1, 101) carrying thick substances under pressure, especially concrete, for changing a wiper (19, 108, 150), especially a ball, which is forced through the pipeline (1, 101) using a pressure medium; the above characterised by a reciprocally displaceable part (7) which has a through pipe (8) which can be aligned with the supply pipe (1) and a pipe chamber consisting of a dummy pipe (9) containing the wiper (19), the bottom (10) of the dummy pipe having a linking channel to the pressure medium connector (15) which is located outside.

2. Pipe fitting according to claim 1, characterised by the fact that the reciprocally displaceable part (7) is designed as a slide, in which the through pipe (8) and the dummy pipe are laid out axially parallel and together form one component.

3. Pipe fitting according to one of claims 1 and 2, characterised by the fact that the pressure medium connector (15) is on a T-piece (14) fitted with a manometer (16) and a device (17) for air-venting or pressure release.

4. Pipe fitting according to the specification of claim 1, characterised by the fact that a through pipe (111, 137, 160) is designed as a curved pivoting yoke whose outlet end (114,138,161) is connected to the feed pipe (101) by means of a pivot joint (115, 139, 162) and whose inlet end is movable on a plate (106, 141, 167) having an opening each for a pipe chamber (107, 146) situated behind the plate and a pipe-shaped inlet (105; 132, 133) from the feed pipe (101), whereby the pipe chamber (107, 146) consists of a dummy pipe containing the wiper (108, 150), the bottom (109, 149) of the dummy pipe having a linking channel to the pressure medium connector which is located outside.

5. Pipe fitting according to claim 4, characterised by the fact that the pivoting yoke connects both the feed cylinders (132, 133) of a piston pump (131), which alternately fill up and feed and which form the pipe-shaped inlet, with the feed pipe (101), whereby the plate (141) has recesses for each feed cylinder (132, 133) and the pipe chamber (130) and is situated on one side of a preliminary feed container for the pump.

6. Pipe fitting according to one of claims 4 or 5, characterised by the fact that the casing (104) has an open construction and that a cleaning body (128) can be introduced into the pipe-shaped inlet (105), the through pipe (111, 160) being aligned with the pipe chamber (107).

7. Pipe fitting according to one of claims 4 to 6, characterised by the fact that the pipe chamber (107) is a closed-bottom tube fitted with a detachable cover (149).

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