EP2576037B1 - Re-mixing device - Google Patents

Description

The invention relates to a post-mixing device for the post-mixing of shotcrete with water with a Wasserzumischteil downstream feeding pipe section, a laxative pipe section and arranged between the feeding and the laxative pipe section post-mixing chamber, which has in the flow direction two mutually under a deflection angle mixing sections with impact surfaces , wherein the flow direction first mixing portion relative to the feeding pipe section with respect to its rectilinear extension at an angle less than 90 ° is arranged.

Such a mixing device is in the EP 1 695 803 B1 reported as known. The post-mixing device or the post-mixing tube has been proven especially when mixing dry mix with water. Namely, a major problem with the dry spray concrete method is to achieve a good mixing of the dry mix with water, achieving a good concrete quality and to produce as little dust as possible at work.

This is effected by the described in the cited document using a Spritzbetondüse with post-mixing chamber. This consists of two mutually arranged at an angle mixing sections and has baffles and reflective surfaces for the supplied mix, which is wetted before entering the post-mixing chamber in a tubular Wasserzumischteil with disposed therein water nozzles with water. The impact surfaces have a conical, V-shaped or concave shape in cross-section, which concentrate the flowing mixture in the cross-sectional direction and substantially contribute to maintaining the flow dynamics.

Another post-mixing device of this kind is in the DE 20 2010 005 526 U1 shown.

With the mentioned Nachmischvorrichtungen or Nachmischrohren good mixing results are achieved. However, there are also applications, in particular depending on the material to be mixed, such. B. in the mix mixed with metal filaments in which the flow conditions and related conditions in the mixing device are impaired.

The present invention has for its object to provide a post-mixing device of the type mentioned, with the optimized flow conditions are achieved in different compositions of the mix, with a good mixing remains guaranteed.

This object is achieved with the features of claim 1. It is provided that the laxative pipe section extends in a straight line extension of the downstream, second mixing section or with respect to the rectilinear one Extension is angled or angled at an angle which is less than the angle between the straight line extension of the second mixing section and the rectilinear extension of the feeding pipe section.

In elaborate, lengthy tests and investigations by the inventor, it has been found that with effective mixing of the mixed material with the water added in the water mixing part, the flow is improved in virtually all relevant mixing conditions, if the transition between the downstream mixing section of the mixing chamber and the subsequent pipe arrangement or the discharge pipe in straight extension of the downstream mixing section or at least at an angle which is less than the angle between the rectilinear extension of the downstream mixing section and the rectilinear extension of the feeding pipe section into the mixing chamber. In this way, a reliable flow of the mixed material is ensured by the mixing chamber, even if the mix z. B. contains relatively large amounts of longer metal fibers, which may have approximately spiral structure. By different orientations within the angle a also different rebound forces can be effected, so that as a side effect the handling can be positively influenced or the supply pressure can be reduced accordingly.

It has been shown that the essential mixing processes in the stated construction of the mixing chamber (see also the above-mentioned publications EP 1 695 803 B1 and the DE 20 2010 005 526 U1 ) already in the transition region between the feeding pipe section and the inflow-side, first mixing section and in particular in the transition region between the first and the second mixing section are effected by the baffles and opposite reflecting surfaces.

With the measures described in the present application, there are also effects on the abrasion in connection with the flow, so that improvements can also be achieved in this respect.

An advantageous embodiment for achieving a reliable mixing under different conditions is that the post-mixing chamber is formed in such a way that the impact surfaces of the first mixing section in its longitudinal direction extending in the flow direction with respect to a rectilinear extension of the feeding pipe section at an angle of 10 ° to 80 ° are arranged and the impact surfaces of the second mixing section are arranged in their longitudinal direction extending in the flow direction with respect to a rectilinear extension of the first mixing section at an angle of 10 ° to 90 °.

The resistance to abrasion is increased by the fact that the impact surfaces of the post-mixing chamber over the entire surface or only part of surface with hard materials such. As ceramics, carbide, steel, Alulegierungen, carbide coatings, enamel, glass or elastic materials such. As rubber or plastic coated.

For the construction and the design or production, there are various advantageous variants in that the entire post-mixing chamber consists of metal, Alulegierungen, ceramic, plastic, rubber or similar material. The thus formed walls of the post-mixing chamber can then with the said resistant Coatings are coated in particular of hard metal or ceramic on the most stressed areas such as impact surfaces and reflective surfaces and input and output areas.

Further advantageous embodiments of the structure are that the Wasserzumischteil is designed as Wasserzumischrohr with water nozzles and is arranged to extract the water nozzles and the post-mixing chamber from a receiving part with water connection pulled out.

The structure, the function and the resistance are further promoted by the fact that the Nachmischkammer is made entirely of plastic or rubber, with certain areas are provided with inserts that improve the resistance to abrasion, the Wasserzumischteil with disposed therein water nozzles and a discharge pipe made of metal, Alulegierungen, ceramic or plastic.

Further advantageous measures, in particular for the production, installation and maintenance consist in that the post-mixing chamber is made in two parts of metal, plastic or rubber and certain areas are provided with inserts, wherein the Wasserzumischteil and the laxative pipe section made as a tubular sleeves with an outer bead in the manner are that when joining the two parts of the post-mixing chamber, the ends of the tube sleeves with the outer bead in corresponding formations of the metal, plastic or rubber parts can be inserted and assembled.

For a reliable function with efficient mixing further contribute to the measures that the impact surfaces of at least the first or the second Have mixing section concave rounded, U-shaped, trapezoidal or V-shaped cross-sectional contour.

An adaptation to different requirements is made possible by the fact that the tube assembly is pivotally connected to the second mixing section by the angle a and fixed at a set angle.

Fig.

1 eine Nachmischvorrichtung mit Nachmischkammer, Wasserzumischteil in Form eines Wasserzumischrohres und einer ausgangsseitigen Rohranordnung mit abführendem Rohrabschnitt und Austragsrohr in perspektivischer Darstellung,

Fig. 2

die Nachmischvorrichtung nach Fig. 1 in anderer perspektivischer Darstellung mit eingetragenen Abschnitten der Nachmischkammer,

Fig. 3

die Nachmischvorrichtung nach Fig. 1 in geöffnetem Zustand der Nachmischkammer in perspektivischer Darstellung,

Fig. 4

die Nachmischvorrichtung nach Fig. 1 in geöffnetem Zustand der Nachmischkammer in einer anderen perspektivischen Darstellung,

Fig. 5

eine seitliche Darstellung der Nachmischvorrichtung mit einem zuführenden Leitungsabschnitt und daran angeschlossener Wasserzuführleitung,

Fig. 6

die Nachmischvorrichtung nach Fig. 5 in perspektivischer Darstellung,

Fig. 7

die Nachmischvorrichtung nach Fig. 5 mit Darstellung eines Winkels α zwischen der Strömungsrichtung der ausgangsseitigen Rohranordnung und der Verlängerung der Richtung des eingangsseitigen Rohrabschnittes und

Fig. 8

die Nachmischkammer nach Fig. 7 in perspektivischer Ansicht mit eingezeichnetem Winkel α.

The invention will be explained in more detail with reference to embodiments. Show it:

FIG.

1 shows a post-mixing device with subsequent mixing chamber, water mixing part in the form of a water mixing tube and an outlet-side tube arrangement with laxative pipe section and discharge pipe in a perspective view,

Fig. 2

the post-mixing device after Fig. 1 in another perspective view with registered sections of the post-mixing chamber,

Fig. 3

the post-mixing device after Fig. 1 in the open state of the post-mixing chamber in a perspective view,

Fig. 4

the post-mixing device after Fig. 1 in the open state of the post-mixing chamber in another perspective view,

Fig. 5

a side view of the post-mixing device with a feeding line section and attached water supply,

Fig. 6

the post-mixing device after Fig. 5 in perspective,

Fig. 7

the post-mixing device after Fig. 5 with representation of an angle α between the flow direction of the output-side pipe assembly and the extension of the direction of the input-side pipe section and

Fig. 8

the postmixing chamber after Fig. 7 in perspective view with drawn angle α.

As Fig. 1 shows, in the present mixing device a Wasserzumischteil in the form of a Wasserzumischrohres 5 with circumferentially arranged water nozzles 5.1 a mixing chamber 1 downstream with a inflow-side, first mixing section 1.2 and a downstream, second mixing section 1.3, at the output side an output-side pipe section 8.1 and a discharge pipe connected thereto 8.2 a pipe assembly 8 (see also Fig. 5 to 8 ) connect. With regard to the construction of the closer Wasserzumischrohres 5 and the mixing chamber 1 is supplementary to the above-mentioned EP 1 695 803 B1 Referenced.

The water mixing tube 5 downstream first mixing section 1.2 is designed so that it is arranged in the flow direction at an angle of 10 ° to 80 ° (with respect to an imaginary extension of the Wasserzumischrohres 5 or a feeding pipe section 1.1), wherein impact surfaces 2 in the first Mixing section 1.2 form a concave rounded (in particular circular or oval), V-shaped or other concave cross-section. As a result, the flowing mixture is concentrated and then flows into the second mixing section 1.3. The second mixing section 1.3 is also provided with impact surfaces 3 which form a concavely rounded, V-shaped or other concave cross-section and is arranged (in the flow direction) opposite (an imaginary extension of the first mixing section 1.2) at an angle of 10 ° to 90 ° , so that between the first mixing section 1.2 and second mixing section 1.3 a blunt or at most right angle is formed. The impact surfaces 2 and 3 of the two mixing sections 1.2, 1.3 are designed wholly or partially straight or curved in the flow direction or longitudinal direction. From the second mixing section 1.3, the mix flows directly or via an intermediate section into the discharge pipe arrangement 8 with the discharging pipe section 8.1 and the discharge pipe 8.2 attached thereto, preferably removably attached.

Due to the inclination of the two mixing sections 1.2, 1.3 with respect to the Wasserzumischrohr 5 results in a steeper hose guide from the bottom to a hose connector part 6.2. This reduces the weight of a feeding hose 7 when holding and guiding the Spritzbetondüse with the post-mixing chamber 1 (see also Fig. 6 ).

Further features of the post-mixing device are shown clearly in the other figures, wherein the Fig. 3 and 4 an interior view of the post-mixing chamber 1 and reflect the impact surfaces 2 and 3 of the first and second mixing section 1.2, 1.3 recognize. These opposite are present in the mixing sections 1.2 and 1.3 reflection surfaces for the mix, so that when flowing through the mixing chamber effective mixing of the mix with the water supplied via the water nozzles results. In Fig. 5 are a receiving part to the water nozzles 5.1, to which a Wasserzuführschlauch is connected, and a hose connector for the dry mix feeding hose 7 and the discharge pipe 8.2 of the pipe assembly 8 shown, wherein the discharge pipe 8.2 is removably attached to the laxative pipe section by means of a clamp.

Like from the Fig. 7 and 8th can be seen, the pipe assembly 8 is connected to the discharging pipe section 8.1 in rectilinear extension of at least the output region of the optionally curved second mixing section, wherein the axis A1 of the discharging pipe section 8.1 and the pipe assembly 8 is shown in the flow direction. Further, an axis A2 in the direction of the extension of the input side of the post-mixing chamber 1 arranged feeding pipe section 1.1 (in this case offset relative to the extension parallel) entered. The pipe assembly 8 with the discharging pipe section 8.1 and the discharge pipe 8.2 or only the discharge pipe 8.2 is arranged in the direction of the axis A1 or at an angle α in the region between the axis A1 and the axis A2, wherein the angle α preferably by a differential angle β of z. B. at least 10 ° or 20 ° (depending on the angle between the two mixing sections 1.2, 1.3 and between the first mixing section 1.2 and the feeding pipe section 1.1) is smaller, ie by the difference angle β is less than the total angle between the two axes A1 and A2. In this case, the tube assembly 8 or only the discharge tube 8.2 can be connected pivotably and fixed at a certain angle by means of an adjustable pivot mechanism or with different manifold sections at the outlet of the second mixing section 1.3 or the discharging pipe section 8.1.

It has been shown that a straight extension of the tube assembly 8 with respect to the second mixing section 1.3 or a small angle α, the flow through the mixing chamber even with mixes with strong flow-inhibiting admixtures such. B. metal threads favored, for example, can have lengths of 3 or 4 cm and crimped or spiral structure. This ensures good mixing effects. Angle α> 0 can be advantageous to reduce recoil forces.

Claims (9)

1. Re-mixing device for the remixing of air-placed concrete with water, with a feeding pipe section (1.1) following a water admixing part, with a discharging pipe section (8.1) and with a re-mixing chamber (1) which is arranged between the feeding pipe section (1.1) and the discharging pipe section (8.1) and which has, in the direction of flow, two mixing sections (1.2, 1.3) standing at a deflection angle to one another and having impact surfaces (2 and 3), the first mixing section (1.2), in the direction of flow, being arranged at an angle smaller than 90° in relation to the feeding pipe section (1.1) with respect to a rectilinear prolongation of the latter,
   characterized in that
   the discharging pipe section (8.1) runs as a rectilinear prolongation of the downstream second mixing section (1.3) or is angled or bent in relation to the rectilinear prolongation at an angle (α) which is smaller than the angle between the rectilinear prolongation of the second mixing section (1.3) and the rectilinear prolongation of the feeding pipe section (1.1).
2. Re-mixing device according to Claim 1,
   characterized in that
   the re-mixing chamber (1) is designed in such a way that the impact surfaces (2) of the first mixing section (1.2) are arranged, in their longitudinal extent running in the direction of flow, at an angle of 10° to 80° in relation to a rectilinear prolongation of the feeding pipe section (1.1), and the impact surfaces (3) of the second mixing section (1.3) are arranged, in their longitudinal extent running in the direction of flow, at an angle of 10° to 90° in relation to a rectilinear prolongation of the first mixing section (1.2).
3. Re-mixing device according to claim 1 or 2,
   characterized in that
   the impact surfaces (2 and 3) of the re-mixing chamber (1) are coated over their entire area or only part of their area with hard materials, such as ceramic, hard metal, steel, aluminium alloys, carbide coatings, enamel or glass, or elastic materials, such as rubber or plastic.
4. Re-mixing device according to one of the preceding claims,
   characterized in that
   the entire re-mixing chamber (1) consists of metal, aluminium alloys, ceramic, plastic, rubber or similar material.
5. Re-mixing device according to one of the preceding claims,
   characterized in that
   the water admixing part is designed as a water admixing pipe (5) with water nozzles (5.1) and is arranged so as to be capable of being withdrawn from a reception part (6.1) with a water connection for the purpose of cleaning the water nozzles and the re-mixing chamber (1).
6. Re-mixing device according to one of the preceding claims,
   characterized in that
   the re-mixing chamber (1) is manufactured entirely from plastic or rubber, specific regions being provided with insert parts which improve resistance to abrasiveness, the water admixing part, with water nozzles formed in it, and the discharge pipe (8.1) consisting of metal, aluminium alloys, ceramic or plastic.
7. Re-mixing device according to one of the preceding claims,
   characterized in that
   the re-mixing chamber (1) is manufactured in two parts from metal, plastic or rubber and specific regions are provided with insert parts, the water admixing part and the discharging pipe section being manufactured as pipe sleeves with an outer bead in such a way that, when the two parts of the re-mixing chamber (1) are joined together, the ends of the pipe sleeves with the outer bead can be inserted into corresponding shaped-out portions of the metal, plastic or rubber parts and can be joined together.
8. Re-mixing device according to one of the preceding claims,
   characterized in that
   the impact surfaces (2, 3) at least of the first or of the second mixing section (1.2, 1.3) possess a concave, U-shaped, trapezoidal or V-shaped cross-sectional contour.
9. Re-mixing device according to one of the preceding claims,
   characterized in that
   the pipe arrangement (8) is connected pivotably at an angle (α) in relation to the second mixing section (1.3) and can be fixed at a set angle.

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