Metal tube float flowmeter with vacuum insulation function

Abstract

This utility model discloses a metal tube float flowmeter with vacuum insulation function, including a flowmeter body comprising a measuring tube and several flanges connected to both sides of the measuring tube; an insulation sleeve containing a negative pressure vacuum chamber and an insulation chamber, the insulation chamber being filled with sand; and a negative pressure box connected to the negative pressure vacuum chamber via a pipe. The insulation sleeve is fitted onto the measuring tube. This utility model achieves insulation of the measuring tube by setting an insulation sleeve on the outside of the measuring tube, with pearl cotton placed between the inner wall of the insulation sleeve and the measuring tube, and an insulation chamber and a negative pressure vacuum chamber inside the insulation sleeve, the insulation chamber being filled with pearl sand. The negative pressure vacuum chamber is connected to the negative pressure box via a pipe, and the negative pressure box evacuates the negative pressure vacuum chamber and the insulation chamber, creating a vacuum state on the inner wall of the insulation sleeve. This prevents the internal heat from affecting the measurement accuracy due to a temperature difference between the internal heat and the environment. This structure is suitable for high or low temperature measurements and measurements with large ambient temperature differences, improving its applicability.

Description

Technical Field

[0001] This utility model belongs to the field of flow meter technology, and in particular relates to a metal tube float flow meter with vacuum insulation function. Background Technology

[0002] The working principle of a metal float flow meter is that as the flow rate changes, the float moves upward. At a certain position, the buoyancy force on the float and the weight of the float reach equilibrium. This flow meter is suitable for measuring the flow rate of small-diameter and low-velocity media.

[0003] Currently, under extreme operating conditions such as steam or low temperature, the accuracy of flow meter measurements is severely affected by the combined effects of drastic changes in the physical properties of the medium, the thermal expansion and contraction of the equipment, and environmental energy exchange.

[0004] Specifically, in steam scenarios, when high-temperature, high-pressure steam passes through a flow meter, insufficient insulation can cause localized condensation of the steam on the pipe surface, forming a liquid water film or a wet steam zone. This process not only alters the density of the medium (wet steam may only be 60%-80% of the density of dry steam), but also generates additional resistance due to droplet impacts on the float or turbine blades, directly disrupting the flow meter's force balance or the linear relationship between speed and flow rate.

[0005] When flow meters are used to measure liquid nitrogen, liquefied natural gas (LNG), or cryogenic liquids, the infiltration of ambient heat causes the medium's temperature to rise and its volume to expand. Without real-time temperature compensation, density changes will directly introduce measurement errors. For example, in liquid oxygen measurement, for every 1°C increase in temperature, the density changes by approximately 0.25%. With a flow meter range of 100 m³ / h, temperature fluctuations alone can cause a deviation of ±0.25 m³ / h. Under cryogenic conditions, material properties change significantly: shrinkage of metal components may increase the gap between the float and the tapered tube, leading to increased leakage; hardening of rubber seals may cause internal leakage, further reducing measurement accuracy.

[0006] In addition, dynamic interference from environmental energy exchange exacerbates measurement instability. In winter, nighttime radiative cooling may cause the pipe surface temperature to plummet to -10°C, while daytime solar radiation may raise it to 20°C. This periodic thermal stress can cause micro-deformation of the flow meter structure, affecting float displacement or sensor sensitivity.

[0007] Chinese patent CN218765428U describes a heating and insulation device for a miniature flow meter. The open sides of the left and right insulation boxes are joined side-by-side between fixing component I and fixing component II, forming a complete cavity. Filler material is placed around the cavity, and a heating plate base is placed on the filler material at the bottom of the cavity. The heating plate is mounted on the heating plate base, and a heating plate fixing plate is close to the filler material at the top of the cavity. A thermocouple temperature sensor is mounted on the heating plate fixing plate and connected to a temperature control device. This invention isolates the display of the miniature flow meter from the heating device, controlling the temperature within the required range and preventing the medium inside the miniature flow meter from solidifying. This effectively avoids shortening the lifespan of the miniature flow meter due to repeated heating. Using aluminum silicate ceramic fiber insulation cotton as the filling material enhances the insulation effect, extends the lifespan of each component, and thus extends the lifespan of the entire device.

[0008] Chinese patent CN216954661U describes a mass flow meter with heating and insulation. The mass flow meter body has a heating jacket on its outer wall, a circulating heating channel inside the heating jacket, a heat exchanger inside the circulating heating channel, and a heat insulation cover outside the heating jacket. The heat insulation cover consists of an outer layer, a middle layer, and an inner layer from the outside in. The outer layer, middle layer, and inner layer each have interlayers on both sides. The two ends of the circulating heating channel are located at the top and bottom of the heating jacket, respectively, and the circulating heating channel is arranged spirally around the inner side of the heating jacket.

[0009] However, existing technologies cannot insulate the measuring pipe from the inside out, so the pipe can only be kept warm by heating during the measurement process. This cannot fundamentally solve the problem of inaccurate measurement caused by the temperature difference between the high-temperature or low-temperature medium transmitted inside the measuring pipe and the outside environment. Utility Model Content

[0010] The purpose of this utility model is to solve the problem that existing technologies cannot insulate the measuring pipe from the inside out, so that the pipe can only be insulated by heating during the measurement process, which cannot fundamentally solve the problem of inaccurate measurement caused by the temperature difference between the high temperature or low temperature medium transmitted inside the measuring pipe and the outside. Therefore, this utility model proposes a metal tube float flowmeter with vacuum insulation function.

[0011] To achieve the above objectives, this utility model adopts the following technical solution: a metal tube float flowmeter with vacuum insulation function, comprising:

[0012] The flow meter body includes a measuring tube and several flanges, with the flanges connected to both sides of the measuring tube;

[0013] An insulation jacket, which has a negative pressure vacuum chamber and an insulation chamber inside, the insulation chamber being filled with sand;

[0014] A negative pressure box is connected to the negative pressure vacuum chamber via a pipe, and the heat insulation sleeve is fitted onto the measuring tube.

[0015] As a further description of the above technical solution:

[0016] Pearl cotton is provided between the inner wall of the insulation sleeve and the flow meter body.

[0017] As a further description of the above technical solution:

[0018] Valves are installed on the pipeline.

[0019] As a further description of the above technical solution:

[0020] The sand is dry perlite.

[0021] As a further description of the above technical solution:

[0022] The insulation sleeve is located between the upper and lower flanges of the measuring tube.

[0023] As a further description of the above technical solution:

[0024] The sandbag is located inside the insulation cavity, the sand is located inside the sandbag, and the insulation cavity is connected to the negative pressure vacuum cavity.

[0025] In summary, due to the adoption of the above technical solution, the beneficial effects of this utility model are:

[0026] 1. In this utility model, an insulation sleeve is set on the outside of the measuring tube, and pearl cotton is placed between the inner wall of the insulation sleeve and the measuring tube. An insulation cavity and a negative pressure vacuum cavity are set inside the insulation sleeve. The insulation cavity is filled with pearl sand. The negative pressure vacuum cavity is connected to a negative pressure box through a pipe. The negative pressure box evacuates the negative pressure vacuum cavity and the insulation cavity, so that the inner wall of the insulation sleeve is in a vacuum state. This achieves insulation of the periphery of the measuring tube, avoiding the temperature difference between the internal heat and the environment from affecting the measurement accuracy. This structure is suitable for high temperature or low temperature measurement and large ambient temperature difference, improving the applicability of the flow meter.

[0027] 2. In this utility model, high-density pearl cotton is filled between the inner wall of the insulation jacket and the outer wall of the measuring tube as an initial heat insulation layer. The interior of the insulation jacket is designed as a double-cavity structure, including an insulation cavity and a negative pressure vacuum cavity. The insulation cavity is filled with micron-sized pearl sand to enhance thermal resistance, and the negative pressure vacuum cavity is connected to the negative pressure box through a pipe. After the negative pressure box is started, the insulation cavity and the negative pressure vacuum cavity are evacuated simultaneously, so that a double vacuum heat insulation layer is formed inside the insulation jacket. By evacuating the vacuum, air convection is eliminated, effectively blocking the conduction of high and low temperature differences between the measuring tube and the environment. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 A cross-section of a metal tube float flowmeter with vacuum insulation function. Figure 1 .

[0030] Figure 2 A cross-section of a metal tube float flowmeter with vacuum insulation function. Figure 2 .

[0031] Figure 3 A three-dimensional metal tube float flowmeter with vacuum insulation function Figure 1 .

[0032] Figure 4 A three-dimensional metal tube float flowmeter with vacuum insulation function Figure 2 .

[0033] Figure 5 A three-dimensional metal tube float flowmeter with vacuum insulation function Figure 3 .

[0034] Legend:

[0035] 1-Flowmeter body; 1a-Measuring tube; 1b-Flange; 2-Insulation jacket; 3-Negative pressure vacuum chamber; 4-Insulation chamber; 5-Pipeline; 6-Negative pressure box; 7-Electric cotton; 8-Valve; 9-Sand. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0039] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0040] In the description of the embodiments of this utility model, it should be noted that the terms "upper" and "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed when in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0041] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0042] Please see Figure 1-5 This utility model provides a technical solution: a metal tube float flowmeter with vacuum insulation function, comprising:

[0043] The flow meter body 1 includes a measuring tube 1a and several flanges 1b, with the flanges 1b connected to both sides of the measuring tube 1a;

[0044] The insulation sleeve 2 has a negative pressure vacuum chamber 3 and an insulation chamber 4 inside, and the insulation chamber 4 is filled with sand 9.

[0045] The negative pressure box 6 is connected to the negative pressure vacuum chamber 3 through the pipe 5, and the heat insulation sleeve 2 is fitted on the measuring tube 1a.

[0046] Pearl cotton 7 is provided between the inner wall of the insulation sleeve 2 and the flow meter body 1.

[0047] A valve 8 is installed on the pipeline 5.

[0048] The sand material 9 is dry perlite. This achieves efficient heat insulation and avoids the impact of moisture in the perlite on the heat preservation effect.

[0049] The insulation sleeve 2 is located between the upper and lower flanges 1b of the measuring tube 1a.

[0050] A sandbag is located inside the insulation cavity 4, and the sand 9 is located inside the sandbag. The insulation cavity 4 is connected to the negative pressure vacuum cavity 3. The sandbag, acting as a carrier for the perlite, prevents particles from shifting or settling due to airflow disturbances under negative pressure, ensuring uniform thermal resistance distribution within the insulation cavity. Simultaneously, the flexible material of the sandbag (such as non-woven fabric) conforms to the curved surface of the measuring tube, eliminating localized thermal bridges. Furthermore, the connection between the insulation cavity and the negative pressure vacuum cavity prevents insufficient vacuum caused by the independent sealing of the insulation cavity.

[0051] Working principle: An insulation sleeve is installed on the outside of the measuring tube, and pearl cotton is placed between the inner wall of the insulation sleeve and the measuring tube. The insulation sleeve contains an insulation cavity and a negative pressure vacuum cavity. The insulation cavity is filled with pearl sand. The negative pressure vacuum cavity is connected to a negative pressure box through a pipe. The negative pressure box evacuates the negative pressure vacuum cavity and the insulation cavity, so that the inner wall of the insulation sleeve is in a vacuum state. This achieves insulation of the periphery of the measuring tube, avoiding the temperature difference between the internal heat and the environment from affecting the measurement accuracy. This structure is suitable for high or low temperature measurements and measurements with large ambient temperature differences, improving the applicability of the flow meter.

[0052] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A metal tube float flowmeter with vacuum insulation function, characterized in that, include: The flow meter body includes a measuring tube and several flanges, with the flanges connected to both sides of the measuring tube; An insulation jacket, which has a negative pressure vacuum chamber and an insulation chamber inside, the insulation chamber being filled with sand; A negative pressure box is connected to the negative pressure vacuum chamber via a pipe, and the heat insulation sleeve is fitted onto the measuring tube.

2. The metal tube float flowmeter with vacuum insulation function according to claim 1, characterized in that, Pearl cotton is provided between the inner wall of the insulation sleeve and the flow meter body.

3. The metal tube float flowmeter with vacuum insulation function according to claim 2, characterized in that, Valves are installed on the pipeline.

4. The metal tube float flowmeter with vacuum insulation function according to claim 1, characterized in that, The sand is dry perlite.

5. The metal tube float flowmeter with vacuum insulation function according to claim 1, characterized in that, The insulation sleeve is located between the upper and lower flanges of the measuring tube.

6. The metal tube float flowmeter with vacuum insulation function according to claim 1, characterized in that The sandbag is located inside the insulation cavity, the sand is located inside the sandbag, and the insulation cavity is connected to the negative pressure vacuum cavity.

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