EP2663435B1 - Admixture piece and housing element for a mixing device - Google Patents

Description

Technical area

The invention relates to a tubular Beigabestück for inclusion in a mixing device for the controlled metered addition of an additive in a pumpable mixture, in particular in a pumpable hydraulically setting mixture, in particular in a shotcrete composition, wherein the Beigabestück over a Beigabestück extending through the mixing section for guiding the pumpable Mixture has and in a wall of Beigabestücks at least one opening into the mixing section opening for introducing the additive is introduced into the mixing section and wherein the Beigabestück at least one sealing element for producing an at least partially fluid-tight connection between the Beigabestück and the mixing device is present.

Another aspect of the invention includes a set of equipment including a loading piece and a housing member. In addition, the invention relates to the use of a Beigabestücks for the controlled metered addition of an additive in a pumpable mixture.

State of the art

The metering in of small amounts of a substance, e.g. An additive in a pumpable mixture is essential in many applications. However, good mixing is often difficult to achieve, especially in heterogeneous mixtures with solids. A particular problem is the addition of additives in hydraulically setting mixtures, which usually have a relatively high solids content of abrasive sand, gravel and cement.

Particularly demanding is the admixing of additives in the processing of shotcrete. Before spraying, the shotcrete flows at high speed through a delivery line with attached spray nozzle. Necessary recipe ingredients, such as Water (in the case of dry sprayed concrete), compressed air and additives (for example solidification accelerator) are usually metered in just before the spray nozzle or at a maximum of about 2.5 m in advance. The now ready-to-use shotcrete mixture then shoots under pressure onto the contact point and compresses so strongly that essentially a ready-compacted concrete structure is created immediately. Accordingly, particularly efficient and robust mixing devices are needed for the shotcrete processing.

Known mixing devices for shotcrete processing usually consist of a tubular Beigabestück, which is designed as a wear part and is kept interchangeable in a special housing. Lateral inlets on Beigabestück allow the addition of an additive into the conveyed through the tubular Beigabestück mixture. Depending on the application different Beigabestücke be used, which differ, for example, in terms of number, size and geometry of the side inlets and / or in view of the cross-sectional geometry of the delivery line.

The EP 1 570 908 A1 (Sika Technology AG) discloses in this regard, for example, a shotcrete nozzle for applying wet shotcrete or dry sprayed concrete with an integrated addition piece for adding an admixture. The Beigabestück has a variety of side channels for introducing additives into the shotcrete. The integrated add-on piece of the shotcrete nozzle is intended to be received in a housing with a connection for the supply of additive. In order for the introduction of the additive controlled and evenly through the side channels of Beigabestückes is sealed in front of and behind the lateral channels in the housing. For this purpose, in the injection concrete nozzle of EP 1 570 908 provided circumferential annular grooves, which are designed to accommodate O-rings. If the area of the loading piece is pushed into a housing with a matching cylindrical opening, the area lying between the O-rings is sealed to form a radial seal. In other commercially available mixing devices, the O-rings used for the sealing are arranged in correspondingly formed grooves in the housing of the mixing device.

However, known mixing devices can only be handled satisfactorily to a degree if the components (housing and insert) are produced from a precision material, such as steel. The Beigabestück example, made of plastic, which is particularly advantageous for weight reasons, resulting in large tolerances. To ensure the tightness of the O-rings in any case, the grooves for the O-rings are usually designed with oversize. However, this results in the insertion of Beigabestücks in the housing, however, a radial interference fit. Due to this interference fit a high effort or special tools are necessary when inserting and removing the Beigabestück what makes handling much more difficult. The publication JP 60 024 359 U discloses a tubular Beigabestück for inclusion in a mixing device for the controlled metered addition of an additive in a pumpable mixture, according to the preamble of claim 1.

Presentation of the invention

The object of the present invention is therefore to provide a Beigabestück associated with the aforementioned technical field, which is easier to handle during installation and removal in or out of a housing and still allows a reliable seal. Another task is to provide a corresponding housing element of a mixing device.

The object with regard to the Beigabestück is achieved by the features of claim 1 according to the invention. Accordingly, the at least one sealing element with respect to a longitudinal axis of the tubular Beigabestücks designed as an axial seal.

Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of the dependent claims.

Specifically, the term "tubular filler" means a tubular member having an inlet and an outlet connected by a fluid conducting channel or conduit. The fluid-conducting channel or the delivery line corresponds to the mixing section of the tubular Beigabestücks. In the mixing section, mixing of the pumpable mixture with the additive takes place. The terms delivery line and mixing section are used synonymously in the present context.

A cross-sectional area of the fluid-conducting channel can be designed to be constant or changing along the delivery line. A shape of the cross-sectional area can be arbitrarily selected according to the intended application, for example, circular, oval and / or polygonal. For fluid dynamic reasons, a circular cross-sectional area is preferred. In particular is the tubular Beigabestück a cylindrical pipe section, in particular with a substantially circular cylindrical conveying line. The term cylindrical pipe piece in the present context includes in particular pipe pieces which have in the region of the lateral surface over protruding sealing elements, flanges and / or tapered pipe sections.

An inner diameter, in particular a minimum inner diameter, of the delivery line is preferably at least 25 mm. A maximum value of the inner diameter of the delivery line measures in particular at most about 100 mm. Particularly preferably, the inner diameter of the conveying line is 32 mm, 38 mm, 50 mm, 60 mm, 65 mm or 85 mm. Thus, the Beigabestück can best combine with standardized components, such as delivery lines, delivery hoses and / or shotcrete nozzles. Furthermore, in such dimensions in particular optimal delivery of different flow rates (in cubic per min) guaranteed by shotcrete compositions. An overall length of the loading piece, measured in the axial direction, is advantageously 30-300 mm, more preferably 50-150 mm.

The "longitudinal axis of the tubular Beigabests" corresponds in particular to the direction predetermined by the fluid-conducting channel or the conveying line, which corresponds in particular to a conveying direction of the pump to be conveyed in the delivery line pumpable mixture. The expression "axial direction" or in the "axial direction" in the present context stands in particular for the direction defined by the fluid-conducting channel or the delivery line.

In the case of a cylindrical pipe section, the longitudinal axis essentially corresponds to the longitudinal central axis and / or the axis of symmetry of the conveying line and / or the tubular Beigabestücks.

The term "sealing element" in the present context, in particular for a molded plastic element. The sealing element is designed so that by a touching contact pressure on a Sealing surface on a part to be sealed results in a fluid-tight connection.

Further, in the present context, the term "radial seal" refers in particular to a seal in which the sealing element, e.g. an O-ring extending substantially radially from a first sealing surface on a first body to a second sealing surface on a second body and sealing a radial clearance. A radial seal is therefore pre-pressed substantially during assembly by a force acting in the radial direction in order to achieve the desired sealing effect.

In contrast, the term "axial seal" particularly designates a sealing element which extends along a longitudinal axis and seals a gap between two axially spaced sealing surfaces. In order to achieve the desired sealing effect, an axial seal during assembly is in particular pre-pressed by a force acting in the axial direction.

In the case of a radial seal, the direction of flow of a leak therefore extends in particular in the axial direction, while in the case of an axial seal, depending on the angle of the spaced sealing surfaces relative to the axis, the flow direction has at least one radial component.

As has been shown in practice, the inventive Beigabestücke can be used in a simple manner in appropriately trained mixing devices or housing elements and also remove it again.

This is particularly because it is possible due to the axial seal according to the invention to completely dispense with radial seals on Beigabestück or in the mixing device. Thus, it is not necessary that the Beigabestück coincides with respect to the diameter dimensions exactly to the inner diameter of the receiving opening in the mixing device, as is the case with conventional Beigabestücken. in the Conversely, an outer diameter of the inventive Beigabestücke can be chosen to be much smaller compared to the inner diameter of the receiving opening in the mixing device, so that the Beigabestück with play in the receiving opening insert or remove it. Also, manufacturing tolerances, which are generally much greater in Beigabestücken plastic than Beigabestücken steel, are largely unproblematic due to the inventive solution.

The axial seal according to the invention nevertheless makes it possible to produce a fluid-tight connection between the loading piece and the mixing device or in the receiving opening. For this purpose, it is sufficient, as will be described in more detail below, when the axial seal on Beigabestück pressed by a force acting in the axial direction force against a sealing surface is kept fixed in the mixing device. This represents a simple, yet extremely effective method of sealing.

As has also been shown, the additions according to the invention are particularly advantageous in the metered addition of an additive into a pumpable hydraulically setting mixture, in particular in shotcrete composition. The shotcrete composition may be in particular a wet, dry or dry shotcrete composition.

Thus, it should be noted that the inventive Beigabestück during installation and removal in or out of a housing is easier to handle and still allows a reliable seal.

In principle, it is also possible to additionally provide one or more radial seals on the beige piece in addition to the at least one axial seal according to the invention. This may be appropriate for specific applications. However, in this case, the inventive advantages are at least partially lost. The axial seal is formed as an annular sealing lip, which in particular in a section, preferably continuously, has a wedge-shaped tapered cross-section. In particular, a region of a wedge tip of the sealing lip is designed as a sealing edge. With such sealing lips mechanically stable and tight axial seals can be realized in the present context. The area of the wedge tip forms a defined sealing edge with a small contact surface. Under the action of a force acting in the axial direction thus results in a high pressure in the region of the support surface, which results in a good sealing effect. The wider region of the wedge tip located behind the region of the wedge tip at the same time ensures high mechanical stability of the sealing lip or of the sealing element.

In particular, a wedge angle of the sealing lip measures 10 ° -80 °, preferably 20 ° -70 °, most preferably 25 ° -35 °. Under the wedge angle in this context, in particular, the angle between the two coinciding in the wedge tip wedge surfaces of the sealing lip is understood. Such acute wedge angle have been found to be particularly suitable with regard to optimum sealing effect and stability.

In principle, however, wedge angles of less than 10 ° or more than 80 ° are possible.

Furthermore, it has been shown that the sealing lip in the region of the wedge tip particularly preferably has a convexly curved edge surface as a sealing edge. As a result, the contact surface of the sealing edge on a surface can be further reduced, since the contact surface in this case approaches a support line. At the same time, with a convexly curved edge surface, the mechanical stability of the sealing lip is improved compared to a sharp-edged wedge tip, since the risk of edge damage, eg due to tearing of the sealing lip in the thin edge region, is reduced. Convex curved edge surfaces are not mandatory. In principle, the sealing lip in the region of the wedge tip can, for example, also be formed with sharp edges or with a flattened sealing edge. According to the invention, the axial seal is arranged on an end face of a flange present on the beige piece. The flange acts as a carrier element for the axial seal. This allows in a simple manner an arrangement of the axial seal on Beigabestück. Preferably, the flange in the axial direction is flush with the tubular Beigabestück.

In principle, however, it is also conceivable that the axial seal is arranged, for example, on an end face of the wall of the tubular beige piece and / or on an end face of a step-like taper and / or a radially tapering taper of the tubular beige piece. According to the invention arranged on the end face of the flange axial seal is at least partially, preferably completely, spaced from the wall of the Beigabestücks, so that there is a groove between the axial seal and the wall. The groove also has in particular a concave curved boundary surface. Due to the spacing of the axial seal, the sealing lip can be pressed better against the conditions of the sealing support in the mixing device. In particular, it is possible in this case that the area of the wedge tip when pressed against the sealing support in the mixing device to a limited extent remains movable in the radial direction and can be pressed against the sealing support better.

This is advantageous, for example, in combination with conically tapered sealing supports in the mixing device, which at the same time enable automatic centering of the sealing lips.

A concavely curved boundary surface of the groove also has the advantage that there are fewer or no edges in the groove area in which material could get stuck. As a result, a possible accumulation of material and the associated risk of clogging is reduced when using the Beigabestücks in a mixing device. In addition, grooves configured in this way can be cleaned more easily.

In principle, however, the axial seal can also be arranged adjacent to the wall of the beige piece. It is also possible to provide a groove with non-concave curved boundary surface. However, in these cases, the advantages mentioned above are at least partially eliminated.

Apart from the possible reinforcing element, the Beigabestück and / or the axial seal is made of a plastic, particularly preferably a plastic having a hardness of 50 - 120 Shore-A, according to another preferred embodiment. Particularly preferably, the plastic has a hardness of 70-95 Shore-A. For example, plastics made of polyurethane are suitable. Such plastics have a good mechanical stability and have an optimal deformability when applying an axial force, so that a good sealing effect is obtained. This has been demonstrated, in particular, by the use of the admixture under relatively harsh conditions in conjunction with hydraulically setting blends, particularly wet, dry or dry shotcrete compositions.

Preferably, the at least one sealing element and / or the axial seal is materially connected to the beige piece. This ensures optimal positioning and sealing effect. In addition, there is no danger that the sealing element could be lost when installing or removing the Beigabestücks.

In particular, the at least one sealing element and / or the axial seal is an integral part of the Beigabestücks. This means, in particular, that the addition piece is designed as an axial seal in the region of the at least one sealing element. In this case, the at least one sealing element and / or the axial seal at least in the region of the at least one sealing element consists in particular of the same material as the beige piece. The Beigabestück and the at least one sealing element or the axial seal in this case form a cohesively connected unit. Particularly advantageous is the Beigabestück made at least in the region of at least one sealing element made of a plastic, more preferably a plastic with a Hardness of 50 - 120 Shore-A. Even more advantageous are plastics of hardness 70-95 Shore-A. Most preferably, the Beigabestück, apart from a possible reinforcing element, completely integrally formed. This means in particular that the Beigabestück together with the axial seal and any other elements, such as the at least one flange, a cohesively connected unit forms. According to an advantageous variant, the addition piece consists of a one-piece cast body and optionally an at least partially embedded reinforcing element. The cast body consists in particular of a plastic, more preferably a plastic having a hardness of 50 to 120 Shore A. Even more advantageous are plastics of hardness 70-95 Shore-A. As a result, particularly stable Beigabestücke can be produced in an economical manner. In particular, a Beigabestück of a one-piece cast body can be produced in a single operation without time-consuming post-processing. A possible reinforcing element, in particular an annular reinforcing element is advantageously at least partially, in particular completely embedded in the cast body so that it does not come into contact with the media or the pumpable mixture in the mixing section. Such a reinforcing element can be embedded directly in the casting of the cast body in this.

In principle, the Beigabestück but also consist of several individual and non-positively and / or positively connected parts.

In a further advantageous embodiment, there is additionally a further sealing element on the beige piece, which is spaced apart from the at least one sealing element in the direction of the longitudinal axis of the tubular Beigabestücks. The further sealing element is designed in particular as a further axial seal. Most preferably, the further sealing element is configured as an annular sealing lip, which has a wedge-shaped cross section and is designed as a sealing edge, which in the region of the wedge tip particularly preferably has a convexly curved edge surface as a sealing edge. A wedge angle of the sealing lip the further sealing element advantageously measures specific 10 ° -80 °, preferably 20 ° -70 °, more preferably 25 ° -35 °.

In a particularly preferred embodiment, the further sealing element is arranged on an end face of a step-like taper and / or a radially tapered taper of the tubular Beigabestücks. Preferably, the axial seal arranged on the end face of the rejuvenating taper is arranged at least partially, preferably completely, spaced from the wall of the insert, so that there is a groove between the axial seal and the wall which advantageously has a concavely curved boundary surface.

In principle, however, the second sealing element may be attached to a further projecting flange or on an end face of the wall of the tubular Beigabestücks. In principle, it is also possible, instead of or in addition to the sealing lip to provide a differently configured sealing element, which for example has no wedge-shaped cross section, such as an O-ring or a flat gasket with a rectangular cross-section.

In the case of two spaced-apart sealing elements, the opening opening into the delivery line can be arranged, for example, between the at least one sealing element and the further sealing element. The region of the opening in this case can be completely sealed in a housing by the two sealing elements, in particular in the form of axial seals. This is advantageous in view of a controlled metered addition of an additive into a pumpable mixture, in particular into a pumpable hydraulically setting mixture, in particular into a wet, dry or dry shotcrete composition.

Particularly advantageous is a maximum extent, in particular a maximum outer diameter, of the further sealing element in a direction perpendicular to the longitudinal axis and / or a radial direction of the tubular Beigabestücks less than a maximum extent, in particular a maximum outer diameter of the at least one sealing element. Such a configuration makes it possible tubular Beigabestück essentially without any effort with the further sealing element in advance in the axial direction in a correspondingly shaped opening of a housing of a mixing device to push until both the at least one and the further sealing element come to rest on a designated sealing pad. A removal of the tubular Beigabests can then be done in the reverse direction also without effort. In addition, it is ensured in this embodiment that the beige piece automatically comes to rest in a clearly defined position. An accidental mounting of Beigabestücks in the wrong direction is made impossible.

In principle, however, it is also conceivable to design the two sealing elements substantially with the same dimensions and this e.g. to install on the two end faces of the wall of the tubular Beigabestücks. It is also possible to provide the two sealing elements, for example, with substantially the same maximum expansions and to provide a special housing with an at least partially dismantled for the assembly of Beigabestücks opening. However, this eliminates the aforementioned advantages at least partially.

According to a further embodiment, the tubular beige piece preferably has a structural reinforcing element. The reinforcing element is advantageously made of a material with less elasticity than a material of the fluid-conducting channel or the mixing section. In principle, there may also be a plurality of spaced-apart and / or interconnected reinforcing elements.

The reinforcing element may for example be made of plastic, metal and / or a composite material. By means of the reinforcing element, the mechanical stability in subareas, in particular in the radial direction, of the tubular Beigabestücks can be specifically increased, wherein the necessary axial elasticity is maintained.

Particularly preferably, the reinforcing element is made of a metal, in particular steel. As a result, an optimal reinforcement of the tubular Beigabestücks is achieved.

In a particularly advantageous embodiment, the reinforcing element is designed as an annular and / or hollow cylindrical element, in particular as a metal ring. Thus, the reinforcing element can be arranged, for example, in a simple manner in the region of the fluid-conducting channel and thereby has an optimum supporting effect in the radial direction. In principle, however, differently shaped reinforcing elements can also be provided. These may be fibers, grids or braids of fibers, for example. This can also be achieved a reinforcement of the tubular Beigabestücks in the radial direction without losing the necessary flexibility in the axial direction.

A length of the reinforcing element, in particular of a metal ring, in the axial direction of the loading piece is advantageously 5 to 50%, in particular 10 to 30%, of the total length of the loading piece. A thickness of the reinforcing element, in particular a metal ring, is advantageously smaller than the thickness of the wall of the tubular Beigabestücks in the region of the reinforcing element. This achieves an optimum reinforcing effect with compact dimensions and the necessary elasticity in the axial direction. In addition, the reinforcing element can be completely embedded in the wall of Beigabestücks without protruding.

Particularly preferably, the reinforcing element is at least partially, preferably completely, embedded in a wall of the tubular Beigabestücks or the fluid-conducting channel. As a result, it is achieved, in particular, that the addition piece can not be radially deformed under normal conditions and thus the function of the sealing lips is maintained over a wide range. In addition, it is advantageous if the reinforcing element does not protrude in the interior of the tubular Beigabestücks. Thus, no protrusions are formed by the reinforcing element, which among other things could affect the flow behavior of the pumpable mixture in the fluid-conducting channel.

In particular, the reinforcing element is arranged in the region of the fluid-conducting channel or the mixing section. If the Beigabestück about two Has sealing elements, the reinforcing element is advantageously arranged in a region between the two sealing elements. In principle, however, the reinforcing element can also be present in other areas.

In the following, the housing element of a mixing device for the controlled injection of an additive into a pumpable mixture, in particular a pumpable hydraulically setting mixture, in particular a shotcrete composition, is discussed. The housing element comprises a base body with a passage opening, wherein the passage opening is designed for the at least partial reception of a loading piece as described above. The housing element is characterized in particular by the fact that at least one sealing support arranged on the housing element (200) is provided for a sealing element of the loading element designed as an axial seal, and means are provided for applying a force acting on the loading element in the axial direction and / or longitudinal direction of the passage opening, so that the axial seal of an at least partially received in the passage opening Beigabestücks can be pressed by the means for applying the force against the sealing pad. In particular, the housing element also has a connection for feeding the additive into the passage opening.

The passage opening of the housing element is in particular at least partially substantially complementary to the inventive Beigabestück formed. Furthermore, the loading piece can be accommodated coaxially in the passage opening of the housing element.

The interaction of the sealing pad and the means for applying the force handling during installation and removal of a tubular Beigabestück as described above is substantially simplified and at the same time a reliable seal is ensured. In particular, a jamming of the sealing elements of the tubular Beigabestücks in the housing element, as occurs in conventional systems, effectively avoided.

The means for applying an axial force to the loading piece can in principle be selected according to the requirements. For this purpose, the person skilled in a number of suitable technical devices are known. This can e.g. be arranged on the base body or housing element toggle mechanism. The present in the housing element and partially projecting out of the opening tubular Beigabestück can be embraced in this case, for example, by one or more arranged on the toggle mechanism brackets and pressed in tensioning the toggle mechanism in the axial direction into the opening. Likewise, it is conceivable to provide a spring tensioning mechanism in which one or more springs fastened to the housing element and prestressed press the tubular attachment piece in the axial direction into the opening of the housing element. Also conceivable are bayonet-type connection techniques.

Particularly preferred is as a means for applying a force to the Beigabestück a screwed onto the main body union nut. For this purpose, the main body preferably has a screw thread in the region of an outside, in particular an external thread.

The sealing support in the base body and the Beigabestück are dimensioned so that the Beigabestück protrudes from the passage opening of the body out of concern when applied to the sealing pad, so that in particular the protruding from the through hole end of Beigabestücks can be encompassed by the nut.

In particular, the union nut has a first hollow-cylindrical end with a screw thread extending in the direction of the longitudinal axis, in particular an internal thread. At the other end of the nut is located opposite the first end tapered and circular opening with advantage. A diameter of the tapered opening is advantageously at least as large, preferably larger, than the inner diameter of the conveying line of the tubular Beigabestücks and / or at the same time less than a maximum dimension, in particular an outer diameter, of the tubular Beigabestücks at a front end. This allows the union nut the tubular Beigabestück include frontally and at the same time remains an optimal passage for the mixture to be pumped by the mixing device free.

Such a configuration makes it possible in this case to press the present in the housing element and partially protruding from the opening tubular Beigabestück in a simple and reliable manner by a screw movement of the nut in the opening of the housing member. Thereby, the at least one sealing element or the axial seal of Beigabestücks is pressed against the sealing support in the body.

The use of a union nut as a means for applying an axially acting force on the beige piece also makes it possible in a simple manner to connect the mixing device with other components. For example, the union nut may include a pipe, a hose line and / or a shotcrete nozzle with a fastening flange arranged on the input side and connect in a fluid-tight manner to the mixing device. Due to the screw through the union nut pipes, hoses and / or shotcrete nozzles can be used with different flange thickness, the thickness of the mounting flanges can be compensated in many areas.

Advantageously, the at least one sealing support of the base body is designed as a truncated cone lateral surface and / or a conically tapered surface. The truncated cone lateral surface and / or the conically tapered surface are in particular rotationally symmetrical with respect to the longitudinal axis of the main body. An opening angle of the truncated cone lateral surface and / or the conically tapered surface advantageously measures 70-270 ° or a half opening angle, measured to the longitudinal axis or the axis of the conveying direction, of 35-135 °. A truncated cone lateral surface, which is designed as an outer conical surface, advantageously has an opening angle of 180-220 ° or a half opening angle of 90-110 ° (from the longitudinal axis or the axis of the Conveying direction measured). A truncated cone lateral surface, which is designed as an inner cone surface, has in particular an opening angle of 80-100 ° or a half opening angle of 40-50 ° (measured from the longitudinal axis or the axis of the conveying direction). If both an outer conical surface and an inner conical surface are present, a ratio of the opening angle of the outer conical surface to an opening angle of the inner conical surface is advantageously in the range from 1.8 to 2.75. As has been shown this facilitates the centering of the axial seal of Beigabestücks in the body, which improves the overall tightness.

This is particularly advantageous in combination with an axial seal in the form of a sealing lip with a wedge-shaped cross-section, which preferably also at least partially, particularly preferably completely, is spaced from the wall of Beigabestücks. When pressing the wedge tip region of the sealing lip to the sealing support or the truncated cone surface in the mixing device, the sealing lip can move to a limited extent in the radial direction and be pressed against the sealing support even better. As a result, in particular the tightness can be further improved.

In principle, however, a flat sealing surface can also be provided, which is present in particular in a plane perpendicular to an intended insertion direction of the tubular attachment piece and / or perpendicular to the longitudinal axis of the inserted piece inserted into the base body.

According to a further preferred embodiment, there is a further sealing support arranged in the base body for a further sealing element present on the beige piece and designed as an axial seal.

Corresponding Beigabestück with at least two sealing elements in the form of axial seals can be so easily inserted into the receptacle or removed from it, at the same time a high density is achieved. A present on Beigabestück area of the opening for introducing the additive into the delivery line can be sealed on both sides in the housing element. This is with regard to a controlled metered addition of an additive into a pumpable mixture, in particular in a pumpable hydraulically setting mixture, in particular in a wet, dry or dry shotcrete composition, an advantage.

In addition to or instead of the further sealing pad, e.g. a radial seal integrated in the main body may also be provided, e.g. an O-ring. In this case, however, the handling may be difficult.

Preferably, a minimum diameter of the at least one sealing pad is greater than a minimum diameter of the further sealing pad. This allows the inclusion of a Beigabestücks described above with two different sized axial seals. For differently shaped Beigabestücke the sealing pads but may for example also have approximately the same outer diameter.

In this case, the at least one sealing support is preferably designed as an inner cone surface and / or the further sealing support is designed as an outer conical surface. If the Beigabestück present in the housing element between the two axial seals from the outside pressurized, acts on the axial seals radially outwardly and / or inwardly directed force. Due to the configuration of the two sealing surfaces, an associated deflection of the axial seals in the radial direction is effectively reduced or the tightness of the axial seals is additionally increased due to the additional contact forces in the radial direction.

In principle, metals, plastics or composite materials with or without fiber reinforcement come into question as material for the housing element and / or the base body.

As the metal, for example, stainless steel and / or aluminum is suitable. However, the housing element is particularly advantageous from a plastic, in particular polyoxymethylene copolymer, hereinafter called POM-C. Under POM-C is in particular a commercially available at various suppliers polymer based on a structural unit having the formula - [(CH ₂ -O) _n - (CH ₂ -CH ₂ -O-) _m ] to understand. Thereby, the weight of the housing member can be kept low and at the same time is a high ensures mechanical and chemical stability, which is particularly advantageous in connection with pumpable hydraulically setting mixtures, in particular with wet, moist or dry shotcrete compositions. Housing elements made of plastic can be compared to metals or composites also relatively inexpensive to produce, for example by casting.

In a housing element having a base body and a cap nut as a means for applying a force acting in the axial direction of the beige Beigabestücks are according to a particularly preferred embodiment, both the base body and the nut each in one piece of a plastic, in particular POM-C made.

The above-described tubular Beigabestück is advantageously provided together with the housing element also described above as a set of equipment. A distance between the two sealing elements on Beigabestück in the axial direction corresponds in particular substantially a distance of the two sealing pads on the housing element. The passage opening in the housing element is in this case designed in particular such that the loading element can be accommodated at least partially in the passage opening.

From the following detailed description and the totality of the claims, further advantageous embodiments and feature combinations of the invention result.

Brief description of the drawings

Fig. 1

Eine hohlzylindrisches Beigabestück mit zwei als Axialdichtungen ausgelegten Dichtlippen in perspektivischer Ansicht;

Fig. 2

Ein Längsschnitt entlang der Linie A - B durch das Beigabestück aus Fig. 1;

Fig. 3

Ein Gehäuseelement mit zwei Kegelstumpfflächen als Dichtauflagen und einer Überwurfmutter als Mittel zum Aufbringen einer in Axialrichtung und/oder Längsrichtung des Beigabestücks wirkenden Kraft;

Fig. 4

Das mit dem Beigabestück aus den Fig. 1 - 2 bestückte Gehäuseelement aus Fig. 3, welches zusätzlich mit einem Förderschlauch und einer Spritzbetondüse verbunden ist;

Fig. 5

Eine Variante des hohlzylindrischen Beigabestücks aus Fig. 1 mit einem eingegossenen ringförmigen Verstärkungselement im Bereich zwischen den beiden Dichtlippen in einem Längsschnitt.

The drawings used to explain the embodiments show:

Fig. 1

A hollow cylindrical Beigabestück with two designed as axial seals sealing lips in a perspective view;

Fig. 2

A longitudinal section along the line A - B through the Beigabestück Fig. 1 ;

Fig. 3

A housing element with two frustoconical surfaces as a sealing pads and a cap nut as a means for applying a force acting in the axial direction and / or longitudinal direction of the Beigabestücks force;

Fig. 4

The with the Beigabestück from the Fig. 1 - 2 fitted housing element Fig. 3 which is additionally connected to a delivery hose and a shotcrete nozzle;

Fig. 5

A variant of the hollow cylindrical Beigabestücks Fig. 1 with a cast-in annular reinforcing element in the region between the two sealing lips in a longitudinal section.

Basically, the same parts are provided with the same reference numerals in the figures.

Ways to carry out the invention adding pieces

In the Fig. 1 and 2 is a tubular Beigabestück 100 shown. Beigabestück 100 has a hollow cylindrical body 102 with a along the longitudinal axis 101.2 extending circular cylindrical passage 101, which extends completely through the body 102 and serves as a mixing section or conveying line for a pumpable mixture.

At one end, a circumferential flange 105 is disposed on the base body 102. At the other end of the body 102 facing front surface of the flange 105 is an annular circumferential and rotationally symmetrical to the longitudinal axis 101.2 formed first sealing lip 110 is arranged as a sealing element. The first sealing lip 110 is designed as an axial seal and has a wedge-shaped tapering cross section in a direction away from the end face of the flange 105. A wedge angle 111.1 of the first sealing lip 110 is for example about 30 °. In the region of an outer peripheral surface, the sealing lip merges seamlessly into the outer lateral surface of the flange 105.

A region of the free end 111 of the first sealing lip 110 or a region of the wedge tip is convexly curved and forms a sealing edge of the sealing lip 110. The sealing lip 110 is also spaced from the wall of the base body 102 in the radial direction, so that between the wall of the base body 102 and the sealing lip 110 is a first circumferential groove 112 having a concave curved boundary surface.

In the region of the other end, the tubular Beigabestück 100 has a step-like taper or a radially tapering taper, on which a further sealing element in the form of another circumferential sealing lip 120 is arranged. Like the first sealing lip 110, the second sealing lip 120 is designed as an axial seal, has a wedge-shaped tapered cross section and is rotationally symmetrical to the longitudinal axis 101.2. Apart from the reduced diameter in the radial direction, the further sealing lip 120 is substantially the same design and oriented as the first sealing lip 110. Accordingly, the second sealing lip 120 has a wedge angle 121.1 of e.g. about 30 ° and a portion of the free end 121 of the further sealing lip 120 forms a convexly curved sealing edge. The further sealing lip 120 is further spaced apart in the radial direction from the wall of the base body 102, so that between the wall of the base body 102 and the further sealing lip 120 there is a further circumferential groove 121 with a concavely curved boundary surface. The further sealing lip 120 merges seamlessly into the wall of the hollow cylindrical main body 102.

In the middle between the two ends of the tubular Beigabestücks 100 and between the two sealing lips 110, 120 are also six evenly spaced and opening in the radial direction in the circular cylindrical passage 101 openings 103 introduced into the wall of the hollow cylindrical body 102. These serve to introduce an additive into the circular cylindrical passage 101 provided as a mixing section. It is also possible, for example, to provide 4 or 8 openings, which may also have an angle to the longitudinal axis.

A total length of the dunnage piece 100, measured along the longitudinal axis 101.2, measures e.g. about 125 mm. An outer diameter 110.1 of the first sealing lip 110, measured in a direction perpendicular to the longitudinal axis 101.2 of the tubular attachment piece 100, measures e.g. about 100 mm, while an outer diameter 120.1 of the further sealing lip 120, for example, about 87 mm. Thus, the outer diameter 120.1 of the further sealing element is about 13% smaller than the outer diameter of the first sealing element. An inner diameter 101. 1 of the loading piece 100 is, for example, approximately 60 mm.

The tubular Beigabestück 100 is in particular made completely in one piece from a plastic. For example, polyurethane with a hardness of about 50-120 Shore A, for example 75 Shore A or 90 Shore A, is suitable as the plastic.

housing element

Fig. 3 shows a longitudinal section through a housing member 200 which comprises a tubular body 225 with a central passage opening 201. The passage opening 201 extends from a first end 230 to a second end 240 along a longitudinal center axis 201.1 completely through the base body 225 therethrough. In this case, the passage opening 201 is subdivided into a plurality of regions with different inner diameters, wherein all regions are configured rotationally symmetrical with respect to the longitudinal center axis 201.1.

From the first end 230 of the base body 225 ago, the passage opening 201 tapers conically. In other words, the portion beginning at the first end 230 of the passage opening 201 is designed as a truncated cone surface or inner cone surface 210. The inner cone surface 210 serves as a sealing support for an axial seal of a beige added in the body 225 Beigabestücks. This is for example a Beigabestück 100 as in the Fig. 1 - 2 shown. An opening angle of the inner cone surface 210 measures, for example, about 90 ° (measured 45 ° from the longitudinal center axis).

The inner cone surface 210 is adjoined by a first hollow cylindrical section 202 with a constant inner diameter, which merges via a conical intermediate region 203 into a second hollow cylindrical section 204 with an enlarged inner diameter.

The second hollow cylindrical section 204 then leads into a third hollow cylindrical section 205. The transition between the second and the third hollow cylindrical section is designed stepwise as a truncated cone lateral surface or outer conical surface 220, which serves as a further sealing support for a further axial seal of a beige added in the main body 225. An opening angle of the outer cone surface 220 measures e.g. about 200 ° (measured 100 ° from the longitudinal axis).

The third hollow-cylindrical section 205 finally merges into a diameter-widened connection region 206. The terminal area 206 is e.g. designed for connecting a delivery pipe or a delivery hose.

In the region of the second hollow cylindrical section 204, two radial bores 213a, 213b also open out of diametrically opposite directions as supply lines for introducing an additive into the passage opening 201. The one bore 213a is closed, for example, by a closure cap 402, while at the other bore 213b is closed by a curved tubing 400 a hose or pipe 401 is connected. Depending on the application, both holes 213a, 213b can also be equipped with a connecting piece 400.

An inner diameter 202. 1 of the first hollow-cylindrical section 202, which corresponds to a minimum diameter of the inner cone surface 210, is larger than an inner diameter 205. 1 of the third hollow-cylindrical section 205, which corresponds to the minimum diameter of the outer conical surface 220. In other words, the minimum diameter of the further sealing support (outer conical surface 220) is thus smaller than the minimum diameter of the first sealing support (inner conical surface 210) in the housing element 200.

In the region of the first end 230, an external thread 250 is furthermore introduced into the base body 225. On the external thread 250 a union nut 300 is screwed.

The union nut 300 has a first hollow-cylindrical end with an internal thread 301 extending in the direction of the longitudinal axis. At the other end of the union nut, there is a circular-cylindrical opening 302 tapered step-like with respect to the first end. As a result, in the interior of the union nut 300 there is a disk-shaped end face 303 adjoining the opening 302, which is provided as a contact surface for a beige piece and / or further tubular elements. A diameter 302. 1 of the opening is smaller than a diameter of the internal thread 301.

By a screwing movement of the union nut 300 on the external thread 250 of the base body 225, the union nut can be displaced in the axial direction or in the direction of the longitudinal axis 201.1 relative to the base body 225. A disposed behind the opening 302 of the union nut 300 and abutting the end face 303 element, for example, a Beigabestück 100 as shown in the Fig. 1 - 2 can thus be pressed against the housing element. As a result, the union nut can be used as a means for applying a force acting in the axial direction or in the direction of the longitudinal axis 201.1.

The main body 225 and the union nut 300 are advantageously each made in one piece from plastic. As a plastic, for example POM-C is suitable.

equipment set

The loading piece 100 and the housing element 200 together form a set of equipment. A distance of the two sealing edges 111, 121 on the Beigabestück 100 corresponds to a distance between the two sealing pads 210, 220 on the housing element 200. An outer diameter of the Beigabestücks 100 between the two sealing lips 110, 120 is also less than the inner diameter in the first two hollow cylindrical sections 202, 204 and the conical intermediate area 203. As a result, the Beigabestück 100 can be received in the radial direction with play in the passage opening 201.

Fig. 4 shows an assembly comprising the housing member 200 from Fig. 3 with the enclosed therewith Beigabestück 100 from the Fig. 1 - 2 in a longitudinal section. This arrangement corresponds to a mixing device for the controlled metered addition of an additive into a pumpable hydraulically setting mixture, in particular into a wet, dry or dry shotcrete composition.

The first sealing lip 110 of the loading piece 100 lies with its free end 111 or the sealing edge on the inner cone surface 210 of the base body 225. Analogously, the further sealing lip 120 of the add-on piece 100 lies with its free end 121 or the sealing edge on the outer conical surface 220 of the base body 225. The region of the flange 105 protrudes in the axial direction beyond the first end 230 of the base body 225 into the inner region of the union nut 300. Between the flange-side end of the adduct 100 and the end surface 303 of the union nut 300, an inlet-side flange 601 of a shotcrete nozzle 600 is additionally arranged , The outer diameter of the inlet-side flange 601 of the Spritzbetondüse 600 is greater than the diameter of the opening 302 of the union nut 300. By tightening the union nut 300 of the inlet-side flange 601 of the Spritzbetondüse 600 is pressed against the flange-side end of the Beigabestücks 100, whereby the two sealing lips 110, 120 in the axial direction against the respective bearing surfaces 210, 220 are pressed. As a result, there are fluid-tight connections between the sealing lips 110, 120 and the associated bearing surfaces 210, 220. A passing over the connecting piece 400 in the first two hollow cylindrical portions 202, 204 and the conical intermediate portion 203 fluid, such as an additive for a shotcrete composition, thus can flow only through the openings 103 in Beigabestück 100, whereby a controlled addition of the fluid in the mixing section 101 of the loading piece 100 or into a pumpable mixture conveyed therein.

In the connection region 206 of the housing element 200, an open end of a delivery tube or delivery tube 500 equipped with a coupling device is also connected in a manner known per se. Via the conveying pipe or the conveying hose 500, a pumpable mixture, for example a shotcrete composition, can be conveyed into the loading piece 100. An inner diameter of the delivery tube or delivery tube 500 substantially corresponds to the inner diameter 101. 1 of the tubular attachment piece 100.

Fig. 5 shows a further inventive tubular Beigabestück 800 in cross section. This is essentially identical to the Beigabestück 100 of the Fig. 1 and 2 However, in a region between the two sealing elements 810, 820 additionally has a reinforcing element 850. The reinforcing element 850 is formed as a steel ring and completely embedded in the wall of the tubular Beigabestücks 800 or poured. For example, a length of the reinforcing member in the axial direction measures about 17% of the total length of the beige body 800 in the axial direction.

Assembly / disassembly process

The assembly of the arrangement Fig. 4 is possible in a simple way. In a first step, the union nut 300 removed from the base body 225 is pushed over the shotcrete nozzle 600 until the inlet-side flange 601 abuts the disk-shaped end face 303 of the union nut. Subsequently or at the same time, the tubular attachment piece 100 is inserted from the first end 230 into the passage opening 201 of the housing element 200 until the two sealing lips 110, 120 rest on the respective sealing supports 210, 220 in the base body 225. Subsequently, the union nut 300 is screwed with the shotcrete nozzle 600 on the external thread 250 of the body 225 and tightened. When screwing the union nut 300, the two sealing lips 110, 120 are automatically pressed against the associated sealing pads 210, 220. The delivery pipe or hose 500 may be connected at any time regardless of the other components.

For the replacement or removal of the Beigabestücks 100, the union nut 300 is completely dissolved and removed from the body 225. Thereafter, the Beigabstück can be taken at the flange end and pulled out without appreciable force from the passage opening.

The assembly and disassembly process works in the same way with the tubular Beigabestück 800 Fig. 5 ,

test trials

In order to test the pressure resistance of the housing according to the invention, the housing element 200 (FIG. Fig. 3 ) from POM-C with an adjunct 100 ( Fig. 1 - 2 ) made of polyurethane with a hardness of approx. 90 Shore-A. The connection region 206 and the opening 302 of the union nut 300 were each sealed fluid-tight with a blind flange. Subsequently, pressurized water was supplied via the connecting piece 400 and the water pressure was increased continuously. In this case, compressive strengths of the arrangement of up to 50 - 60 bar have been found before by expansion of the material of the nut 300, a pressure relief has taken place. Neither the union nut 300 nor the connection area 206 were damaged, so that the experiments were repeatable several times. This is particularly advantageous in terms of occupational safety, since there is no risk that the housing element or the Beigabestück breaks up and is torn apart, which could cause personal injury.

In order to test the compressive strength of the sealing lips 110 and 120, in addition, the bores 103 were sealed and one of the blind flanges was bored to the opening 101. Thus leakage of the sealing system at approx. 10 bar could be detected by the exit of water through the bore in the blind flange. In other words, the sealing system is tight up to a pressure of about 10 bar.

In appropriate experiments with the Beigabestück 800 off Fig. 3 Leaks have only resulted at approx. 30 bar. Thus, this sealing system is even tight up to a pressure of about 30 bar.

The supporting pieces 100 ( Fig. 1 - 2 ) and 800 ( Fig. 5 ) made of polyurethane with a hardness of 75 and 90 Shore A and the housing elements 200 ( Fig. 3 ) of POM-C have also been tested in conventional sprayed concrete applicator arrangements under various conditions. As it has been shown, the devices according to the invention are at least as well suited for the application of shotcrete as conventional systems, but the handling in cleaning and replacing the loading piece is significantly better.

However, the embodiments described above are to be understood merely as illustrative examples, which may be modified as desired within the scope of the invention.

It is likewise possible, in addition to the two sealing lips 110, 120, to attach further sealing elements, in particular further sealing lips. At best, conventional radial seals can also be provided. This makes it possible to further improve the sealing effect and / or to realize a separate metering of different additives at different positions in the axial direction of the loading piece.

It is also possible, in addition to or instead of the openings 103, to provide further or otherwise formed openings, for example slots, in the wall of the beige piece.

When housing member 200 off Fig. 3 For example, it is also conceivable to replace the inner cone surface 210 and / or the outer conical surface 220 by flat annular surfaces in order to simplify in particular the production of the housing.

In addition, instead of or in addition to the radial bores 213a, 213b, the housing element 200 can have additional or differently configured feed openings.

The mixing section 101 of the loading piece 100 and / or the passage opening 201 of the housing element 200 may also have a tapered cross-section. This can be expedient, for example, for realizing a current transformer.

Likewise, it is also possible, the Beigabestück 100, the main body 225 and / or the nut 300 partially or completely made of a material other than plastic, for example made of steel and / or aluminum. Instead of Beigabestücks 100 can in the equipment set, the arrangement of Fig. 4 or in the assembly / disassembly process and the tubular Beigabestück 800 Fig. 5 be used.

Claims (12)

1. Tubular admixture piece (100) for receiving in a mixing device for controlled metering of an additive into a pumpable mixture, particularly into a pumpable hydraulically setting mixture, in particular into a spray concrete composition, wherein the admixture piece (100) has a mixing section (101) extending through the admixture piece (100) for conveying the pumpable mixture, and, in a wall of the admixture piece (100), at least one opening (103) leading into the mixing section is provided, for the purpose of introducing the additive into the mixing section (101), and wherein, on the admixture piece (100), at least one sealing element (110) is present for establishing an at least partially fluid-tight connection between the admixture piece (100) and the mixing device, wherein the at least one sealing element (110) is designed in reference to a longitudinal axis (101.2) of the tubular admixture piece (100) as an axial seal characterized in that the axial seal (110) is arranged on a front side of a flange (105) formed on the admixture piece (100) and is arranged spaced at least partially, preferably completely, away from the wall (102) of the admixture piece (100), so that a groove (112) is present between the axial seal (110) and the wall, wherein the groove (112) comprises in particular a concavely curved delimitation surface.
2. Tubular admixture piece according to Claim 1, characterized in that the sealing lip comprises in at least one section, preferably continuously, a wedgeshaped converging cross section, wherein particularly an area of a wedge tip (111) of the sealing lip is designed as sealing edge.
3. Tubular admixture piece according to Claim 2, characterized in that a wedge angle (111.1) of the sealing lip measures 10° - 80°, preferably 20° - 70°, and particularly preferably 25° - 35°.
4. Tubular admixture piece according to one of the previous claims, characterized in that at least one additional sealing element (120) is present, which is spaced in the direction of the longitudinal axis (101.2) of the tubular admixture piece (110) away from at least one sealing element (110), and wherein particularly the additional sealing element is also designed as an axial seal.
5. Admixture piece according to Claim 4, characterized in that a maximum extent (120.1) of the additional sealing element (120) in a direction perpendicular to the longitudinal axis (101.2) of the tubular admixture piece (100) is smaller than a maximum extent (102.1) of the at least one sealing element (110).
6. Tubular admixture piece according to one of the previous claims, characterized in that the admixture piece (100) consists of a single-piece cast body and optionally a reinforcing element embedded at least partially therein, wherein the cast body consists in particular of a plastic, and particularly preferably a plastic having a Shore A hardness of 50-120.
7. Apparatus set comprising a tubular admixture piece (100) according to one of the preceding claims and a housing element (200) of a mixing device for the controlled injection of an additive into a pumpable mixture, particularly into a pumpable hydraulic setting mixture, in particular a spray concrete composition, wherein the housing element (200) comprises a base body (225) with a through-flow opening (201), and the through-flow opening (201) is designed for receiving at least partially an admixture piece (100) according to one of Claims 1-6, characterized in that at least one sealing support (210) - arranged on the housing element (200) - is present for a sealing element of the admixture piece (100) designed as an axial seal, and means (300) are present for exerting a force acting in the axial direction and/or longitudinal direction of the through-flow opening onto the admixture piece, so that the axial seal of an admixture piece (100) received at least partially in the through-flow opening (201) can be pressed by the means (300) for exerting force against the sealing support.
8. Apparatus set according to Claim 7, characterized in that, as means (300) for exerting a force onto the admixture piece, a union nut that can be screwed to the base body is present.
9. Apparatus set according to one of Claims 7-8, characterized in that additionally an additional sealing support (220) arranged in the base body (225) is present for an additional sealing element present on the admixture piece (100) and designed as an axial seal.
10. Apparatus set according to one of Claims 7-9, characterized in that the at least one sealing support (210) is configured as an inner cone surface and/or the additional sealing support (220) is configured as an outer cone surface.
11. Apparatus set according to Claim 9 or 10, with an admixture piece (100) according to one of Claims 5-6, wherein a spacing of the two sealing elements (110, 120) on the admixture piece (100) corresponds substantially to a spacing of the two sealing supports (210, 220) on the housing element (200).
12. Use of a tubular admixture piece (100) according to one of Claims 1-6 for metering an additive into an pumpable mixture, particularly into a pumpable hydraulic setting mixture, and in particular into a spray concrete composition.

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