JPS58225279A - Mixing valve - Google Patents

Abstract

PURPOSE:To minimize the amount of waste grout in the mixing valve upon changing the concentration of the grout by a method wherein a flow regulating valve and a non-return valve are provided linearly and opposingly while a mixing chamber is provided therebetween. CONSTITUTION:When the stock solution of the grout is introduced into a reserving tank and a grout pump 5 is operated under mixing the grout by a mixer 2, the stock solution 18 of the grout arrives at the non-return valve 4 through a suction pipe 3. On the other hand, pressurized water from a water feeding port 10 is sent to the flow regulating valve 7 through a water feeding pipe 8, water, whose amount is regulated so as to obtain a predetermined concentration of the grout, joins with the stock solution of the grout inflowed through the non-return valve 4 and is sucked into the grout pump 5 after being mixed in a line mixer 6. The excess grout is returned into the line mixer 6 through a returning pipe 13 and the grout of a suitable amount is poured into ground 19 from a pouring pipe 14 through a pouring port 20.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mixing valve characterized in that a flow rate adjustment valve and a check valve are arranged facing each other, and a mixing chamber is provided between them, and the mixing valve. The present invention also relates to a mixing valve characterized in that a line mixer is installed in communication with the mixing chamber.

During ground improvement work in dam construction, the grout injected into the ground is mainly a slurry of water and cement, or a slurry of water, cement, and bentonite. In order to avoid sudden blockage of the small voids inside the grout and clogging of the injection hole, construction specifications etc. instruct that a thin concentration of grout be first injected and then gradually switched to a higher concentration grout. There is.

The above grout composition is usually expressed as a weight ratio of water and substances other than water, such as water and cement, and the weights of water, cement, and bentonite contained in the grout are W and C, respectively.
1 and B, the concentration of cement slurry is -,
The concentration of cement bentonite-based 33 is expressed in terms of C1B, and grouting is generally performed when this value is in the range of 70 to 100%.

Manufacturing of grout: There are two methods: measuring each ingredient and mixing and stirring to achieve a predetermined concentration, and another method of manufacturing grout with the highest concentration in advance and using it as a stock solution by adding water to the stock solution. In some cases, the grout can be made to the desired concentration, but in either case, the stirring capacity of the mixer normally used is 2'00 mm, so most of the grout production is done at 200 mm.
The grout concentration switching standard is performed in op units and is based on the specified injection amount described in the construction specifications, and each concentration is made up of multiples of the JO type.

The criteria for changing the grout concentration can be roughly divided into: 1) Switching according to a specified time;

Switching according to the specified injection amount.

3. Switching based on the amount of injection per hour.

Although it is broadly classified into K, based on the basic principle of injecting a large amount of cement or cement and bentonite between the short pieces and the past construction results, the above-mentioned L.

In most cases, switching of 3 and 3 is used together, and independent switching is rarely performed.

Therefore, if the concentration has to be changed even though there is some residual amount in the mixer, the remaining amount will be discarded. It has also been reported that 7~/q% of the amount was wasted.

As mentioned above, in conventional grouting work, a large amount of the grout that has been painstakingly manufactured is discarded, which is not only extremely uneconomical, but also involves a lot of waste, such as the cost of disposing of the discarded grout. This invention has been made in view of the above, and can be used not only for mixing water and cement in grouting work, but also for mixing various fluids.

Embodiments of the present invention will be described in detail below, taking grout injection in dam construction as an example, with reference to the accompanying drawings.

Figure 1 shows an example of a grout injection system, where / is a storage tank equipped with an agitator, 3 is a suction pipe connected to the storage tank /, and DA is a suction pipe installed midway through the suction pipe 3. On the left is the grout pump attached to the end of the check valve t of the suction pipe 3, and on the left is the line mixer installed between the check valve t of the suction pipe 3 and the grout pump S. , 7 is a flow tp regulating valve installed in the water supply pipe g branched from between the check valve DA and the line mixer B, 9 is the water supply pipe g,
A water flow rate detector installed between the flow tX control valve 7 and the water supply port 10, // is a discharge pipe installed on the left side of the grout pump, /, 2 is an automatic return valve installed on the discharge pipe // , /3 is the return pipe installed between the automatic return pulp /2 and the line mixer B, /II is the injection pipe installed at the end of the discharge pipe /l, and 1g is the grout installed at the injection pipe Hiroshi. Flow rate detector, /6 is injection tube /Il
The grout pressure detector /7 is branched and installed ahead of the grout flow rate detector /S, and /7 is based on the value measured by the grout flow rate detector /S and the grout pressure detection 'g%/B. The automatic return pulp control device controls the automatic return valve /2, 1g is the grout stock solution, /9 is the ground, and θ is the injection port.

A grout stock solution is prepared in a mixer (not shown in FIG. 1), and is introduced into the storage tank. When the grout pump 3 is operated while stirring with the stirrer λ, 7 g of the grout stock solution in the storage tank/ Lightly reach the check valve μ. -The pressure water supplied from the power water supply port 10 is the water supply pipe g
The water is sent to the flow rate adjustment valve 7 through the water flow rate detector t, and the amount of water is adjusted so that the grout has a predetermined concentration. 6 and sucked into the grout pump S,
The grout discharged from the grout pump S is discharge head/l.
through the automatic return valve /2, the flow rate is preset by the automatic return pulp controller /7 on the basis of the values measured by the grout flow rate detector /3 and the grout pressure detector //); The automatic return valve /2 is controlled so that the pressure is maintained, excess grout is returned to the line mixer B via the return pipe /3, and an appropriate amount of grout is transferred to the injection pipe /3.
Dakara grout flow rate detector/! It is injected into the ground/q via r and injection port 20.

In the above embodiment, the line mixer B is provided so that the grout stock solution and water that join together through the check valve t and the flow rate adjustment valve 7 are well mixed, but in order to make the device smaller and lighter, When a static line mixer that performs mixing using the energy of the fluid itself is used as a 2-in mixer, the fluid to be mixed does not flow in continuously, and if the fluid flows intermittently, there may be a portion where mixing cannot be performed. Therefore,
If a mixing valve that integrates the check valve DA, the regulating valve 7, and the line mixer B is used, the stock grout solution and water will be better mixed and will flow in continuously.

FIG. 2 shows the above-mentioned mixing valve/example, in which 2/ is a hollow cylindrical pulp body 1. 22 is a hollow cylindrical stem guide detachably inserted into the upper part of the pulp body, and 23 is integrated into the lower part of the stem guide 22. 2'l is the pulp stem inserted into the stem guide 2, 2S is the pulp stem, and the pulp 1. ．． 2B is the pulp stem with the threaded part 27, the stem guide holder which is screwed to the pulp stem 21 and fixed to the valve body 21 with bolts etc., and the water inlet provided in the wall of the 2gL valve body 2/. The structure constitutes a flow rate regulating valve, and the pulp stem 2 is controlled by an actuator (not shown).
When 'l is rotated, the pulp stem 2'l moves upward or downward depending on the direction of rotation due to the action of the threaded core, and the gap between the left side of the pulpco and the pulpcoat 3 at the lower end of the pulp stem changes, and the water inlet The scenery of the water flowing in from 2g changes. Therefore, by adjusting the movement of the actuator using an automatic control device or the like, the amount of water flowing in can be automatically adjusted.

On the other hand, a ball guide 29 and a ball valve seat 3θ are removably housed in the lower part of the valve body 2/.
These are held by a valve seat receiver 3/ fixed to the valve body 2/ with bolts etc., and a ball 32 is provided inside so as to close the central opening of the ball valve seat 30.
is housed and constitutes a check valve. 1
1 When the grout bong is operated, the ball 32 floats along the ball guide 9 due to its suction action, and the ball 32 floats up along the ball guide 9 and enters the grout stock solution inlet 3 formed below the valve seat receiver 3.
The stock grout solution flows in from g.

Immediately, the water flowing in from the gap between the pulp 2S and the valve seat 23 and the grout stock solution sucked in by the floating ball 32 on the ball valve seat 30 are formed between the flow rate adjustment valve and the check valve and mixed. They collide and merge in the chamber 33 to create a turbulent flow, and after being mixed in advance in the mixing chamber 33, they flow continuously into the line mixer 6 from the outlet provided in the mixing chamber 33, and are further mixed in the line mixer 6. The mixture is completely mixed and moves from the grout outlet 3 to the grout pump S.

The line mixer 6 has a line mixer element 36 inserted into a two-in mixer casing 33 made of the same member as a general piping member, and the twin mixer element 31. It has a simple structure in which it is fixed to the line mixer casing 3S by a mixer element presser t2 fixed with bolts or the like, and a grout return port 37 is provided on the side of the line mixer casing 35 near the mixing chamber 33.

In the figure, 39 is the oil filler port, GUO is the oil reservoir, and Hiroshi/ is the 0 ring.

The mixing valve shown in Fig. 2 explained above is made by integrating the check valve ②, the flow rate adjustment valve 7, and the line mixer ② in the grout injection system diagram shown in Fig. 1, and this mixing valve is Used in place of the reverse valve g, flow rate adjustment valve 7, and line mixer B in the figure, the grout stock solution inlet 3g is connected to the storage tank/side suction pipe 3, the water inlet 2g is connected to the water supply pipe g, and the grout outlet is connected to the suction pipe 3 on the storage tank/side. 3'l to the suction pipe 3 on the graft pump S side
If connected to the grout, it is possible to inject even better quality grout into the ground more efficiently than in the grout injection explained in FIG.

In the embodiment described above, when the flow rate adjustment valve is fully closed, the entire suction amount is sucked into the grout pump from the grout storage tank, but when the flow rate adjustment valve is gradually opened, pressure water flows into the grout pump. The amount of grout stock solution sucked from the storage tank decreases accordingly, and as a result, the concentration of grout discharged from the grout pump becomes thinner. Also, if you open the flow rate adjustment valve and try to inject water in an amount larger than the suction capacity of the grout pump, the check valve will not open, so the stock grout solution will not be sucked into the grout pump, and only water will be discharged from the grout pump. , a water push or permeability test may be performed prior to grouting. Furthermore, the automatic return pulp/2, return pipe/3, automatic return valve control device/7, and grout return port 37 are not necessarily required. The fluid mixed in a line mixer contains cement, bentonite, etc., and cement is hydraulic, so Atsugi uses line mixers that have a simple structure and are easy to clean. It is preferable to use a line mixer, such as Japanese Patent No. SS3QIG, which has no moving parts and makes use of fluid flow.

The mixing valve of the present invention can be used not only for mixing grout but also for mixing other fluids such as powder and liquid. A mixing valve that simply has a stop valve and a flow rate regulating valve facing each other and a mixing chamber between them is also effective for mixing fluids.
0 This invention is constructed as described above, and when the mixing valve of this invention is used for grout injection, the concentration of grout is arbitrarily and continuously adjusted by automatically controlling the opening degree of the flow rate regulating valve. It is possible to minimize the amount of waste without producing excess grout, and since grout of any concentration can be obtained at any time, construction can be quickly adapted to the ground conditions. In addition, the device is also smaller and lighter, and has the advantage of being able to efficiently inject grout in dam construction work where working conditions are poor.

[Brief explanation of the drawing]

Claims (3)

[Claims] (1) A mixing valve characterized in that a flow rate adjustment valve and a check valve are arranged facing each other, and a mixing chamber is provided between them. (2) A flow tpI regulating valve and a check valve are disposed facing each other, and a mixing chamber is provided between them, and a line mixer is attached to the mixing valve in communication with the mixing chamber. A mixing valve featuring: (3) The mixing valve according to claim 1, characterized in that a surplus material return port is provided at the line mixer or between the line mixer and the mixing chamber.