JPH0324389A - Special nonreturn valve - Google Patents

Abstract

PURPOSE:To prevent generation of abnormalily high pressure so as to simplify discharge of a washing liquid by installing a nonreturn valve body having a small diameter through hole provided at its center portion. CONSTITUTION:Highly viscous air mortar is forcibly fed into a pipe P1 by a pump and lifts up a valve body 4 to as high as a stopper 6 and is allowed to enter into a case 2 from a clearance between a valve seat 3 and the valve body 4 and pass through a space 9, and is fed into a pipe P2, and thus force feed work of the air mortar is carried out. When the work is stopped air mortar on the upper portion of the valve body 4 is allowed to pass through a through hole 5 and flow back into a pipe P1 and so water-hammer phenomenon does not occur near the delivery port of the pump nor does generation of abnormalily high pressure occur. A washing liquid is fed from the upper end of a pipeline and then falls down while washing the inside of the pipeline and reaches a nonreturn valve and is then allowed to pass through a through hole 5 and falls down so that washing is simplified.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is used in the construction of skyscrapers to use lightweight mortar, extremely small-diameter, high-strength, high-strength high-rise buildings that contain a large amount of air for the purpose of heat insulation and fire resistance. This invention relates to a special check valve that is useful when installed in a pressure pipeline when viscous air mortar is pumped.

[Conventional technology and its problems]

When constructing a skyscraper, it is necessary to pump lightweight mortar or highly viscous air mortar, which has an extremely small diameter and high strength and contains a large amount of air, from the ground to the top floor of the building. However, when pumping with such high pressure, the air in the air mortar expands when it stops, causing a water hammer phenomenon near the pump outlet.
There is a risk that abnormally high pressure will occur, causing damage to the pump discharge valve and pressure pipe.

[Problem to be solved by the invention]

Therefore, the problem to be solved by the present invention is that by arranging one or more of them in a pressure-feeding pipeline as necessary, it is possible to prevent the generation of abnormally high pressure due to the above-mentioned water hammer phenomenon when the pressure-feeding operation is stopped. The purpose of the present invention is to provide a special check button t that makes it possible to easily clean the pressure-feeding pipeline after the pressure-feeding work is completed.

[Means to solve the problem]

The present invention has been made with the aim of solving the above-mentioned problems, and its configuration is such that if a fluid passage is formed inside a case with pipe connections at the top and bottom, a small diameter pipe is formed in the center. The special check valve of the present invention is characterized in that it houses a check valve body provided with a through hole. One or more units are installed near the pressure pump side of the pipeline or in the pipeline, and when the pressure feeding operation of the air mortar is stopped, the air mortar on the upper part of the valve body is moved to the center of the valve rest. It is possible to prevent the generation of abnormally high pressure caused by the water hammer phenomenon that occurs near the discharge port of the pump by passing through the provided through hole and flowing backward in the pipe connected to the lower pipe connection part, and also, After the pressure-feeding operation is completed, the cleaning operation can be facilitated by flowing cleaning water from above.

〔Example〕

Next, an example of implementation of the present invention will be explained with reference to the drawings.

1 is a cross-sectional view taken along the line B--B--B in FIG. 2, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG.

In the figure, 1 is a lower case provided with a lower pipe connection part C, and 2 is watertightly attached to the lower case 1. An upper pipe connection portion D is provided in the upper case. 3 is upper case 2
A valve seat 4 fixed on the lower case 1 is a check valve body, and a small diameter through hole 5 is provided in the center.

Reference numeral 6 denotes a stopper in the shape of a cross on a plane with a through hole 7 in the center, which is fixed to the valve seat 3 via a strut 8, and is attached to the valve body 4.
A space 9 through which mortar flows is formed between the inner wall of the L part case 2 described in 11q.

In addition, in the figure, 10 is an O-ring.

The above items 1 to 10 constitute a special check foot as an example of the present invention. Then, the pressure feeding pipes 1゜■ and P2 are connected to the lower and upper pipe connecting parts C and D, and when the high viscosity air mortar is forced into the pipe P■ by a pump (not shown), the air mortar becomes The valve body 4 is pushed up to the stopper 6 by pressure, enters the case 2 through the gap between the valve seat 3 and the valve body 4, is fed into the pipe P2 through the space 9, and is discharged from the tip of the pressure pipe. Is this how air mortar is pumped? When this pressure-feeding operation is stopped, as mentioned above, in conventional check valves, the air in the air mortar expands and a water hammer phenomenon occurs near the discharge port of the pump, generating abnormally high pressure. In the special check valve of the invention, since the through hole 5 is provided in the center of the foot body 4, the air mortar on the upper part of the well body 4 flows backward into the vibe P through the through hole 5. , the water hammer phenomenon does not occur near the discharge port of the pump, and therefore there is no risk of abnormally high pressure occurring.

That is, now, the inner diameter of the through hole 5 of the valve body 4 is d, the length is also f, the friction loss coefficient is f, the density of the air mortar is ρ, the flow velocity in the through hole 5 is υ, and the acceleration of gravity is g. Then, the pressure loss ΔP of the air mortar passing through the through hole 5 is Δp = 4f-Q/d・ρυ2/2g (this is the standard formula shown in general hydraulics), and this pressure loss Δ
P usually changes into thermal energy and increases the temperature of the air mortar, so if the pressure increase due to the water hammer phenomenon is converted to the above ΔP, an abnormal increase in pressure due to the water hammer phenomenon can be avoided. becomes possible.

Further, the through hole 5 of the valve body 4 is also used for cleaning the pipeline after the end of pressure feeding. That is, when the cleaning liquid is sent from the upper end of the pipeline, the cleaning liquid descends while cleaning the inside of the pipeline, and when it reaches the special check 4t of the present invention, it passes through the through hole 5 and descends to facilitate cleaning. be.

Although only one check valve has been described above, a plurality of the special check valves of the present invention may be installed in the pressure pipeline, and the through holes 5 may have different diameters. You may arrange things in order.

〔Effect of the invention〕

The special check valve of the present invention is as described above, and as shown in the embodiment, by disposing it near the high-pressure pump side of the high-viscosity air mortar pressure-feeding pipeline, it is possible to prevent the problem from occurring immediately after the pressure-feeding pump stops. While it is possible to prevent the occurrence of water hammer phenomenon and prevent the generation of abnormally high pressure, ensuring the safety of the pump discharge valve and pressure delivery pipe, it is also possible to ensure the safety of the pump discharge valve and pressure delivery pipe. The cleaning liquid can be easily discharged by utilizing the water head due to the difference in water head and by using the through hole of the valve body.

Therefore, the special check valve of the present invention is suitable as a check valve disposed in a pipeline for pumping a highly viscous air mortar containing a large amount of air that has a small diameter and high strength.

[Brief explanation of drawings]

The drawings show an example of the implementation of the present invention, and FIG. 1 is a sectional view taken along the line B--B--B in FIG. 2, and FIG. ↓... Lower case, 2... Upper case, 3... Valve seat, 4... Valve body, 5... Valve body through hole, 6... Stopper, 7... Stroke through hole. Hole, 8... Support, 9...
... Space that becomes a flow path, C ... Lower pipe connection part, D.
・Upper pipe connection part

Claims (1)

[Claims] 1. A special device characterized by forming a fluid passage inside a case with pipe connection parts formed in the upper and lower parts, and housing a check valve body with a small diameter through hole in the center part. non-return valve.