JPH11300732A - Pipeline for feeding cleaning water for agitator vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a feeding branch pipe for feeding cleaning water and a switch valve from being clogged with cured cement and insoluble calcium in a green concrete mill where a rotary tank of an agitator vehicle is cleaned by using the cleaning water contg. cement being rich in calcium content, in particular being unhydrated. SOLUTION: A switch valve 5, pref. a butterfly valve is provided in a feeding branch pipe branched from a main pipe for feeding a cleaning water contg. unhydrated cement and a setting retarder and the switch valve 5 is positioned at the highest position of the feeding branch pipe. The butterfly valve is a valve wherein a disc which can be brought into hermetical contact with the inner periphery of a water passage is provided in the water passage in the valve and switching is performed by rotating the disc by using the diameter of the disc as a rotating shaft.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing water injection pipe for washing a returning agitator wheel in a ready-mixed concrete plant using water containing a large amount of calcium. The present invention relates to a washing water injection pipe for an agitator wheel, which prevents a phenomenon that an insoluble calcium compound or a cement hardened substance adheres to block or narrow a pipe. 2. Description of the Related Art Conventionally, returned water used for washing the inside of a rotary drum of an agitator car includes water used in a factory, water collected from rainwater, and washing wastewater in the factory. Uses water. In cleaning, a plurality of injection branch pipes branched from the main pipe are arranged in a rotary drum of an agitator wheel that has been moved back to a fixed position so that water can be independently injected into a drum of each parallel agitator wheel. However, water used in a ready-mixed concrete factory has a large amount of calcium, and when used for a long period of time, there has been a phenomenon that a calcium-containing hardened material is fixed and a branch pipe is blocked or narrowed. [0003] The cement in the concrete or mortar adhering to the returned agitator wheel is not yet completely hardened and is in an unhydrated state. Patent No. 2651537 discloses that the hardening of cement in sludge water containing unhydrated cement, which is generated in washing and drainage of agitator vehicles and other uncondensed cement produced in a ready-mixed concrete plant, is delayed until the next day or later, and the water is mixed into fresh concrete or mortar kneading water. A technique of blending and reusing is disclosed. When this technology is implemented, it is preferable to use sludge water also for the washing water itself of the agitator vehicle, in which case the washing water contains unhydrated cement,
The phenomenon in which cement hardens and adheres to the pipe wall of the pipe was remarkable. [0004] Since sludge water is constantly flowing in the main pipe, the hardened cement adhered to the pipe wall is negligible. On the other hand, in the branch pipe branched from the main pipe, the sludge water stagnation in the branch pipe occurs because the open / close valve is closed except when the agitator wheel is washed, and the cement in the sludge water stagnated gradually in the branch pipe. Due to sedimentation and hardening, a layer of the cement-hardened material accumulates on the pipe wall to narrow the pipe, and it is necessary to frequently replace the pipe. Therefore, there has been a demand for a technique that can be used without replacing pipes for a long period of time without causing pipe narrowing even when washing water containing unhydrated cement flows. An object of the present invention is to solve the above-mentioned problems, and the structure of the present invention is to provide an open / close valve, preferably a butterfly valve, at an injection branch pipe branched from a main pipe at a ready-mixed concrete plant. Wherein the on-off valve is located at the highest position of the injection branch pipe, and preferably the washing water supplied from the main pipe contains unhydrated cement and a setting retarder. And The butterfly valve is a valve that is provided with a disk that can be in close contact with the inner periphery of the water passage in a water passage inside the valve, and that is opened and closed by rotating the disk around the diameter of the disk as a rotation axis. According to the present invention, a butterfly valve having a simple structure, to which a calcium-containing hardened body such as a cement hardened body is unlikely to adhere, is used as an opening / closing valve, and the butterfly valve is arranged at the highest position of a branch pipe. And, it has an inverted V-shape with the open / close valve at the top. as a result,
From the calcium located at the apex, the washing water in the injection branch pipe flows down naturally or returns to the main pipe. That is, after the valve is closed, the cleaning water remaining at the tip from the valve falls naturally and there is no room for the cured body to adhere. Further, the remaining washing water between the valve and the main pipe flows through the main pipe washing water, so that the pressure between the branches becomes negative and is absorbed by the sludge water in the main pipe. At this time, since the branch pipe is located higher than the main pipe, the washing water of the branch pipe is easily returned to the main pipe according to the inclination of the branch pipe. [0007] The present invention is mainly carried out in a ready-mixed concrete factory. An increasing number of factories use sludge water containing unhydrated cement and a setting retarder as washing water for equipment to which ready-mixed concrete containing unhydrated cement has adhered. The sludge water after separating the aggregate from the sludge water is used as a part of cement and water when manufacturing new concrete and mortar, and the sludge water is also used as washing water for agitator vehicles. It is used again as sludge water. In such a factory, since the washing water itself contains unhydrated cement, that is, cement that has not been hardened yet, the washing water remaining in the pipes and on the opening / closing valve remains stationary. If left for a long time, the cement settles and hardens in the branch pipe and adheres and hardens to the inside of the pipe and the valve itself, closing the pipe and shortening the life of the open / close valve. The invention is particularly preferably used in such factories. FIG. 1 is a side view in which washing water is injected from the tip of the injection branch pipe of the present invention into the agitator wheel after the contents have been discharged for cleaning. FIG. 2 is a main pipe, the injection branch pipe and an opening / closing valve. FIG. 3 is an explanatory diagram of a butterfly valve. In FIG. 1, the agitator wheel 1 that has returned after discharging the contents is placed under a tip 3 of an injection branch pipe that branches off from the main pipe 2 and is washed with washing water of a rotary tank of the agitator wheel. Make entrance 4 come. After stopping the agitator wheel 1 at this position, the opening and closing valve 5 is opened, and the washing water is injected into the rotary tank 6 from the injection branch pipe tip 3 through the opening and closing valve 5. The washing water flows obliquely upward from the main pipe 2 through the injection branch pipe base 7, passes through the opening / closing valve, and flows obliquely downward at the injection branch tip 3. Opening / closing valve 5 is main pipe 2
At a higher position, the injection branch base 7 slopes upward,
The tip 3 of the injection branch is inclined downward. The inclination angle is such that the angle θ between the horizontal line x in FIG. 2 and the injection branch pipe base 7 is 7 ° or more, preferably 10 ° or more.
More preferably, it is 15 ° or more. In addition, the angle θ between the injection branch pipe tip 3 and the vertical line y in FIG.
It is preferably at least 20 °, more preferably at least 30 °. As the on-off valve 5 used in the present invention,
A butterfly valve, a ball valve, and the like are used in addition to a pinch valve of a type that closes a water passage in the valve by pneumatic or manual pressure, and among others, a butterfly valve best prevents adhesion of a hardened cement body. As shown in FIG. 3, the butterfly valve 8 is provided with a disk 10 in a water passage 9 in the valve, and a rotating shaft 13 is provided in the diameter direction of the disk 10.
And an opening / closing handle 11 is provided on an extension of the rotating shaft 13. FIG. 3 shows a state in which the butterfly valve 8 is fully opened. However, if the opening / closing handle 11 is rotated by 90 °, the disk 10 becomes a state shown by an imaginary line, and a state 12 in which the water passage 9 is closed. In the closed state, the disk 10 comes into close contact with the inner periphery of the water passage 9. In a factory where the present invention is carried out, a rotary tank of an agitator truck which has returned and transported the contents, as well as a device to which fresh concrete adhered in the factory are washed with a setting retarder. Washed with water. The obtained waste water is led to an aggregate separation tank to add an appropriate amount of setting retarder to the sludge water after separating the aggregate, and it is stored and used as new mixed water for ready-mixed concrete from the next day. . The sludge water concentration is 20% by weight or less, preferably 10% by weight or less. This sludge water contains a sufficient retarder and is used as washing water for a rotary tank. The main pipe 2 was disposed above the rear wall of the agitator car washing room, and the sludge water was supplied to the main pipe 2. From the main pipe 2, ten injection branch pipe bases 7 were branched by being inclined upward at an angle of 15 ° from the horizontal line x while maintaining the interval at which the agitator wheels 1 were arranged side by side without difficulty.
A butterfly valve 8 shown in FIG. 3 was attached to the tip of each injection branch pipe base 7. The tip 3 of the injection branch further extends downward from the butterfly valve 8 at an angle of 40 ° with respect to the vertical line y. The opening and closing handle is 9 between the fully open state and the closed state.
Although the structure has been described as being rotatable by 0 °, a structure that can be rotated may be used. In this embodiment, the injection branch pipe base 7 is
cm. In general, the base of the injection branch pipe 7 is 5 to 30 cm, and the shorter the injection branch base 7 is, the shorter the hardened material prevents blocking. In this embodiment, one year or more has passed, but the work is proceeding smoothly without obstruction of the valve and the injection branch. According to the present invention, in which the on-off valve is provided at the highest position of the injection branch pipe, the rotary tank of the agitator wheel can be prepared by using washing water containing a calcium-rich, particularly unhydrated cement. In the ready-mixed concrete factory, the trouble that the injection branch pipe for injecting the washing water and the opening and closing valve are blocked by the hardened cement and insoluble calcium has been drastically reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing an agitator vehicle after discharging contents.
It is a side view which wash | cleans by injecting wash water from the injection | pouring branch pipe front-end | tip of this invention. FIG. 2 is an explanatory diagram showing a relationship among a main pipe, an injection branch pipe, and an on-off valve. FIG. 3 is an explanatory diagram of a butterfly valve. [Description of Signs] 1 Agitator wheel 2 Main pipe 3 Injection branch pipe tip 4 Wash water injection port 5 Open / close valve 6 Rotary tank 7 Injection branch pipe base 8 Butterfly valve 9 Water passage section 10 Disk 11 Open / close handle 12 Close water passage section State 13 Rotation axis

Claims (1)

Claims: 1. A flushing water for an agitator wheel, wherein an opening / closing valve is provided on an injection branch pipe branched from the main pipe, and the opening / closing valve is located at the highest position of the injection branch pipe. Injection piping. 2. The cleaning water injection pipe for an agitator wheel according to claim 1, wherein the cleaning water in the main pipe is cleaning water containing unhydrated cement. 3. The washing water injection pipe according to claim 1, wherein the washing water in the main pipe is a washing water containing a setting retarder. 5. The washing water in the main pipe is raw consludge containing unhydrated cement and a setting retarder, and the injection branch pipe extending from the main pipe toward the on-off valve is set at 7 ° with respect to a horizontal line. The tip of the injection branch pipe, which is inclined upward at the above angle and extends from the on-off valve, is inclined downward at an angle of 7 ° or more with respect to the vertical line. 5. A flush water injection pipe for an agitator wheel according to any one of items 1 to 4.