JP5968059B2 - Asphalt injection pipe for asphalt plant - Google Patents

Description

  The present invention relates to an asphalt injection pipe installed in an asphalt plant for producing an asphalt mixture that is a road pavement material.

  Asphalt plant mixers, for example, asphalt that injects and supplies a predetermined amount of asphalt into the mixer as described in Patent Document 1 (Patent No. 4117213) and Patent Document 2 (Patent No. 41733084). A supply device is installed. As shown in FIGS. 5 to 7, for example, the asphalt supply apparatus includes an asphalt metering tank 103 in the vicinity of the mixing tank 102 of the mixer 101, and an asphalt injection having a plurality of injection nozzles 104 above the mixing tank 102. The pipe 105 is disposed horizontally, the asphalt measured in the asphalt measuring tank 103 is sent to the injection pipe 105 by the supply pump 106, and the asphalt is injected and supplied from the respective injection nozzles 104 into the mixing tank 102. Like to do.

  Further, the injection nozzle 104 provided in the asphalt injection pipe 105 has a substantially U-shaped elbow structure, and its base end is attached to the upper side of the injection pipe 105, and the injection nozzle at the tip of the nozzle generated after the asphalt injection The rear sag from 107 is suppressed. Although the rear sag can be suppressed to some extent by configuring the injection pipe 105 as described above, some asphalt inevitably remains in the bottom of the injection pipe 105 and the injection nozzle 104 as shown in FIG. Therefore, a heater 108 is provided inside and outside the injection pipe 105 so that the residual asphalt remains in the injection pipe 105 so that the residual asphalt does not cool and harden in the injection pipe 105 as it is. The fluidity is maintained by keeping the temperature.

Japanese Patent No. 4117213 Japanese Patent No. 4173804

  However, the configuration of the injection pipe 105 is somewhat complicated and requires the heater 108 and its power supply equipment, which necessitates considerable apparatus costs and running costs. Further, if the shipment interval of the asphalt mixture becomes longer, the asphalt remaining in the injection pipe 105 will be exposed to the heating from the heater 108 for a long time, and in some cases, carbonization / deterioration will occur, and the fluidity will be impaired. The pipe 105 and the injection nozzle 104 may be blocked. In such a case, the injection pipe 105 may be replaced or the like. However, since the operation involves the attachment and detachment of the heater 108 and the wiring, it is complicated and requires an appropriate time. In order to be forced to stop the operation, a device that is as easy to maintain as possible is required.

  In view of the above-described points, an object of the present invention is to provide an asphalt injection pipe for an asphalt plant that does not require a heater for heat insulation and is relatively inexpensive and easy to maintain.

In order to solve the above-described problems, an asphalt injection pipe of an asphalt plant according to claim 1 is provided with an injection pipe having a plurality of injection nozzles disposed above a mixing tank of a mixer for mixing asphalt mixture, and the injection pipe In the asphalt injection pipe of the asphalt plant in which the asphalt supplied via the injection nozzle is injected into the mixing tank, the central portion in the longitudinal direction of the injection pipe is bent into a mountain fold shape. The bottom of the lower injection pipe where the asphalt flows down is provided with a discharge port for discharging the asphalt in the pipe into the lower mixing tank, and the injection pipe. The asphalt remaining inside is caused to flow down and discharged from the discharge port .

Further, the asphalt blowpipe asphalt plant according to claim 2 is characterized in that it has secured the removable flange of the mixing tank to the injection pipe end edge of the front Stories low position side.

According to the asphalt injection pipe of the asphalt plant according to claim 1 of the present invention, the substantially central portion in the longitudinal direction of the injection pipe is bent in a mountain fold shape, and the gradient is directed toward both ends with the pipe central portion as a top portion. As the asphalt discharge outlet in the pipe is provided at the bottom of the lower injection pipe and the asphalt remaining in the injection pipe flows down and is discharged from the discharge outlet.・ It is possible to discharge relatively quickly at the time of supply, and it is possible to suppress stagnation / residue in the pipe. As a result, there is no need for a heater facility for keeping the residual asphalt in the pipe, and it is inexpensive and easy to maintain. It becomes possible. In addition, the asphalt in the pipe can be discharged from the two discharge ports at both ends of the pipe, and the flow path to the discharge is as short as about half of the pipe length at the longest, so that quicker discharge is possible.

Further, according to the asphalt blowpipe asphalt plant according to claim 2, wherein when since the injection pipe end edges a low position side to secure the removable flange of the mixing tank, the clogging of the jetting pipe has occurred However, since the heater equipment is not provided, maintenance work such as replacement can be performed relatively easily and in a short time through the flange for attaching / detaching the pipe edge.

It is explanatory drawing which shows one Example of the asphalt injection pipe of the asphalt plant which concerns on this invention. It is a partially cutaway principal part enlarged view of FIG. It is BB expanded sectional drawing which abbreviate | omitted a part of FIG. It is a figure equivalent to FIG. 3 of another Example. It is a figure equivalent to FIG. 1 explaining the conventional asphalt injection pipe. FIG. 6 is an enlarged view of a main part of the notch in FIG. 5. It is AA expanded sectional drawing which abbreviate | omitted a part of FIG.

  In the asphalt injection pipe of the asphalt plant of the present invention, for example, the injection pipe that is disposed over the mixing tank of the mixer is folded in a mountain fold shape so that the substantially central portion in the longitudinal direction of the pipe is the top. It bends and forms a gradient so that it gradually decreases from the center of the pipe toward both ends. In addition, the bottom of both ends of the injection pipe on the lower side is provided with a discharge port for discharging the asphalt in the pipe into the lower mixing tank, and the pipe edge is for attaching / detaching to the mixing tank. The flange is fixed.

  When asphalt is supplied into the mixing tank of the mixer by the asphalt injection pipe having the above-described configuration, the asphalt is pumped into the injection pipe by a supply pump and mixed from a plurality of injection nozzles provided at predetermined intervals on the pipe. Inject and supply into the tank. On the other hand, asphalt that remains in the injection pipe without being injected is divided and flows down toward both ends of the pipe from the top of the center of the pipe according to the gradient formed in the pipe. It is discharged relatively quickly.

  In this way, the asphalt can be prevented from staying and remaining for a long time in the injection pipe, so there is no need for a heater for maintaining the residual asphalt and auxiliary facilities for power supply, which are required in the past, which is advantageous in terms of cost. In addition, it becomes possible to eliminate clogging of the pipe due to carbonization / deterioration of residual asphalt. In addition, even if there is a problem such as blockage in the injection pipe, it does not have a heater or its associated equipment, so it can be replaced relatively easily and in a short time via the flange for attaching and detaching the pipe edge. This makes it possible to perform work, and is a useful device that is easy to maintain.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows an asphalt supply device mounted on a plant main body of an asphalt plant, and an asphalt metering tank 3 is provided in the vicinity of a mixing tank 2 of a mixing mixer 1 for asphalt mixture. An asphalt injection pipe 5 made of steel pipe provided with an injection nozzle 4 is stretched over.

  The asphalt injection pipe 5 communicates with the asphalt metering tank 3 through a supply pipe 6, and a predetermined amount of asphalt measured in the asphalt metering tank 3 is injected by a supply pump 7 for asphalt pressure feeding interposed in the supply pipe 6. The asphalt is injected and supplied from the injection nozzles 4 into the mixing tank 2 through the pipes 5. In addition, as shown in FIG. 1, for example, in a mountain fold shape of about 3 to 5 degrees so that the substantially central portion in the longitudinal direction of the injection pipe 5 located above the substantially central portion of the mixing tank 2 becomes the top portion. It bends and forms a gradient so as to gradually decrease from the center of the injection pipe 5 toward both ends.

  The injection nozzle 4 employs a very short straight pipe structure as shown in FIG. 3, for example, instead of the conventional elbow structure, and has a base end portion fixed to the bottom of the injection pipe 5 and suspended. In addition, the injection port 8 at the tip of the nozzle faces the lower mixing tank 2 so that the asphalt sent from the injection pipe 5 to the injection nozzle 4 does not stay or remain in the nozzle more quickly than the injection port 8. It is set as the structure injected into.

  Instead of the straight nozzle structure, the spray nozzle 4 may be directly drilled at the bottom of the spray pipe 5 as shown in FIG. 4. In this case, the structure is simpler. This is advantageous in terms of cost and maintenance. Further, the position, number, diameter, and the like of the injection nozzle 4 and the injection port 8 ′ can be appropriately changed within a range in which the smooth injection performance of asphalt can be maintained. For example, as shown in FIG. Two may be provided at positions shifted from the bottom by about 60 degrees to the left and right. In that case, asphalt can be sprayed to the mixing tank 2 in a wider range, and an improvement in dispersibility can be expected.

  In addition, the bottoms of both ends of the injection pipe 5 on the lower side are respectively provided with discharge ports 9 for discharging asphalt flowing down according to the gradient formed in the pipe toward the lower mixing tank 2. In this embodiment, the discharge port 9 is slightly smaller than the diameter of the injection nozzle 4 and has a substantially similar straight pipe structure. When asphalt is supplied into the pipe, the discharge port 9 and the discharge port 9 are also connected. Asphalt is jetted. The discharge port 9 can be opened and closed by a stopper or the like. For example, when the injection pressure from the injection nozzle 4 at the end of the injection pipe 5 is insufficient, the discharge port 9 at the base end side of the pipe is used. May be closed and adjusted. Further, a flange 10 for attaching to and detaching from the mixing tank 2 is fixed to an end edge portion of the injection pipe 5.

  When the asphalt injection pipe 5 having the above-described configuration is used to inject and supply asphalt into the mixing tank 2 of the mixer 1, a predetermined amount of asphalt measured in the asphalt measurement tank 3 is injected by the supply pump 7. 5 is injected and supplied from the injection nozzles 4 (and the discharge ports 9) into the mixing tank 2. At this time, each injection nozzle 4 has a very short straight pipe structure instead of the conventional elbow structure, and is provided with a nozzle base end attached to the bottom side of the injection pipe 5 so as to hang down. Asphalt sprayed more quickly is discharged without remaining in the nozzle.

  In addition, in the injection pipe 5, a slight gradient is formed in the pipe so that the central portion is the top and gradually decreases from the central portion toward both ends, and asphalt discharge is provided at both ends of the lower pipe. Since the asphalt remaining in the pipe without being injected is divided into the front and rear sides at the center of the injection pipe 5 and flows down to both ends of the lower pipe, It is discharged from the outlet 9 and put into the lower mixing tank 2.

  At this time, for example, the injection pipe 5 is formed in a straight pipe structure so as to be inclined so as to gradually become lower toward the distal end side, so that a gradient is formed, and a discharge port 9 for asphalt discharge is provided at the lower end of the pipe. Anyway, the residual asphalt in the pipe can flow down and be discharged from the discharge port 9, but the central portion of the injection pipe 5 located near the center of the mixing tank 2 becomes the top as in this embodiment. By folding in this way, the flow path required for the residual asphalt in the pipe to be discharged from each discharge port 9 is about half of the pipe length at the longest, which enables discharge in a relatively short time. Thus, for example, asphalt in the pipe can be taken out into the mixing tank 2 within one batch of the mixing processing time, and it is possible to effectively suppress post-sagging over two batches or more. .

  As described above, according to the asphalt injection pipe 5 of the present invention, the asphalt staying and remaining in the injection nozzle 4 and the injection pipe 5 can be suppressed. There is no need for power supply equipment, which is not only advantageous in terms of equipment cost and running cost, but also the residual asphalt in the pipe is carbonized and deteriorated due to overheating by the heater, causing a problem such as blockage of the injection pipe 5 This is suitable for maintenance. Even if the injection pipe 5 is clogged, it does not have a heater for retaining residual asphalt or its power supply equipment, so that it is relatively easy to attach and detach via the attachment / detachment flange 10 fixed to the pipe edge. In addition, the replacement work can be performed in a short time, and it becomes a preferable device that is easy to maintain.

DESCRIPTION OF SYMBOLS 1 ... Mixer 2 ... Mixing tank 4 ... Injection nozzle 5 ... Injection pipe 8 ... Injection port 9 ... Discharge port 10 ... Flange for attachment / detachment

Claims (2)

An asphalt in which an injection pipe having a plurality of injection nozzles is disposed above a mixing tank of a mixer for mixing asphalt mixture, and asphalt supplied through the injection pipe is injected from the injection nozzle into the mixing tank. In the asphalt injection pipe of the plant, a substantially central portion in the longitudinal direction of the injection pipe is bent in a mountain fold shape to form gradients toward both ends with the pipe central portion as a top portion, and a low level that is the asphalt flow destination The bottom of the injection pipe on the side is provided with a discharge port for discharging the asphalt in the pipe into the lower mixing tank, and the asphalt remaining in the injection pipe is caused to flow down and discharged from the discharge port. Asphalt injection pipe for asphalt plant. Before SL low position side of the injection claim 1 asphalt blowpipe asphalt plant according to the pipe end edge, characterized in that it has secured the removable flange of the mixing tank.

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