Nozzle flowmeter special for black and grey water

Abstract

The utility model discloses a special nozzle flowmeter for black grey water, which relates to the field of flowmeter structures and comprises a flowmeter body, the flowmeter body is provided with a measuring pipeline, an annular nozzle body is fixed in the measuring pipeline and consists of a conical inlet section and a throat, the inner diameter of the throat is matched with the small diameter of the conical inlet section, and the inner diameter of the throat is matched with the small diameter of the conical inlet section. The throat part is fixedly connected with the small-diameter end of the nozzle body; a flow inlet of the nozzle body is positioned at the front end of the conical inlet section, and a flow outlet of the nozzle body is positioned at the rear end of the throat part; and the outer diameter of the nozzle body is matched with the inner diameter of a measuring pipeline. The utility model meets the flow measurement of black and gray water and similar working conditions, and has higher wear resistance and erosion resistance and longer service life.

Description

Technical Field

[0001] The utility model relates to the field of flow meter structures, in particular to a nozzle flow meter special for black and grey water. Background Art

[0002] In the coal chemical industry, the measurement of the black ash water flow rate of the coal gasifier is the focus and difficulty of measurement. The medium characteristics are that the liquid contains solids, is high pressure and high temperature, and has a certain degree of corrosiveness. The fluid has serious erosion on the process pipeline and flowmeter, and the service life becomes the key performance of the flowmeter for this purpose.

[0003] Existing flow meters either have a short service life or are expensive, and have different defects, such as wedge flow meters, venturi tube flow meters and electromagnetic flow meters. Among them, the wedge flow meter has serious one-sided erosion due to the biased flow of the flow field, and the pipe opposite the wedge is the most seriously eroded point. In addition, some fluids have high flow rates, which doubles the erosion, and the service life of the flow meter cannot meet the requirements. In the measurement of black and gray water flow, the venturi tube flow meter is generally made of integral forgings, and the flow channel is sprayed with tungsten carbide. Therefore, the cost of the venturi tube flow meter is very high, and because the low-pressure pressure taking position of the venturi tube flow meter is at the throat of the flow meter, the pressure-drawing hole should not be opened too large, and sometimes the pressure-drawing hole will be blocked. Since black and gray water is high temperature, high pressure and contains solids, the failure rate of electromagnetic flow meters is generally high. The existing electromagnetic flow meters are generally changed to wedge or venturi tube flow meters.

[0004] Therefore, a new flow meter is proposed for measuring the flow of black and gray water. Utility Model Content

[0005] The purpose of the utility model is to provide a nozzle flow meter dedicated to black gray water in order to solve the above-mentioned problems, so as to meet the flow measurement requirements of black gray water and similar working conditions, and to have high wear and erosion resistance and long service life.

[0006] The technical solution adopted by the utility model is as follows: a nozzle flowmeter specially used for black and gray water, comprising a flowmeter body, the flowmeter body having a measuring pipe, an annular nozzle body fixed in the measuring pipe, the nozzle body consisting of a conical inlet section and a throat, the inner diameter of the throat matches the small diameter of the nozzle body, and the throat is fixedly connected to the small diameter end of the conical inlet section; the inlet of the nozzle body is located at the front end of the conical inlet section, and the outlet of the nozzle body is located at the rear end of the throat; the outer diameter of the nozzle body matches the inner diameter of the measuring pipe.

[0007] Furthermore, the nozzle body is an integrated structural component.

[0008] Furthermore, the inner wall of the measuring pipe and the inner wall of the nozzle body are both coated with a wear-resistant coating.

[0009] Furthermore, the cone inlet angle of the nozzle body is 30°-90°.

[0010] Furthermore, the length of the throat is 0.3-0.5 times the inner diameter of the throat.

[0011] Furthermore, the flow meter body also includes two pressure-taking tubes, both of which are connected to the inside of the measuring pipeline, and the nozzle body is located between the two pressure-taking tubes.

[0012] Furthermore, the distance between the pressure taking position of the pressure taking tube and the end of the nozzle body is 1 / 3-1 / 2 of the inner diameter of the measuring pipe.

[0013] Furthermore, both pressure-taking pipes are provided with pressure-taking devices, and the pressure-taking devices are connected to the differential pressure transmitter.

[0014] Furthermore, a mounting base is fixed on the outer wall of the measuring pipe, and the differential pressure transmitter is assembled on the mounting base.

[0015] Furthermore, both ends of the measuring pipeline are provided with connecting flanges.

[0016] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0017] The flow meter disclosed by the utility model meets the flow measurement requirements of black grey water and similar working conditions, has high wear and erosion resistance and long service life, and effectively solves the problems of low relative outflow coefficient, bias flow erosion, short service life, high cost of Venturi tube and small size of pressure tapping port of wedge-shaped flow meter. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention will be described by way of examples with reference to the accompanying drawings, in which:

[0019] Figure 1 It is a structural schematic diagram of the nozzle flowmeter disclosed in the utility model;

[0020] Figure 2 It is a schematic diagram of the structure of the nozzle body disclosed in the utility model;

[0021] Markings in the figure: 1-measuring pipe; 2-nozzle body; 21-conical inlet section; 22-throat; 3-wear-resistant coating; 4-pressure taking pipe; 5-pressure taking device; 6-differential pressure transmitter; 7-mounting base; 8-connecting flange. DETAILED DESCRIPTION

[0022] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0023] Any feature disclosed in this specification, unless otherwise stated, can be replaced by other equivalent or alternative features with similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0024] Example 1

[0025] like Figure 1-Figure 2 As shown, a nozzle flowmeter dedicated to black and gray water includes a flowmeter body, the flowmeter body has a measuring pipe 1, and a ring-shaped nozzle body 2 is fixed in the measuring pipe 1. After the black and gray water enters the measuring pipe 1, it enters the nozzle body 2; the nozzle body 2 is composed of a conical inlet section 21 and a throat 22, and the inner diameter of the throat 22 does not change, which is equivalent to a straight pipe; the inner diameter of the throat 22 matches the small diameter of the conical inlet section 21, and the throat 22 is fixedly connected to the small diameter end of the nozzle body 2; the inlet of the nozzle body 2 is located at the conical inlet section 2 1, and the outlet of the nozzle body 2 is located at the rear end of the throat 22; the outer diameter of the nozzle body 2 matches the inner diameter of the measuring pipe 1; the fluid enters the nozzle body 2 from the inlet, and under the action of the conical inlet section 21, flows out from the outlet through the throat 22; since the inner diameter of the throat 22 is smaller than the inner diameter of the measuring pipe 1, the flow velocity of the fluid will increase and the pressure will decrease after passing through the nozzle body 2, that is, there is a pressure difference between the upstream and downstream of the nozzle body 2, and the flowmeter body only needs to obtain the pressure upstream and downstream of the nozzle body 2 to obtain the flow rate of the fluid in the measuring pipe 1.

[0026] In this embodiment, the nozzle body 2 is annular. Compared with the wedge-shaped flowmeter, the fluid enters the nozzle body 2 from the inlet and is ejected from the outlet. The fluid will not flow deviated, thereby reducing the erosion of the measuring pipe 1 and effectively improving the service life of the flowmeter.

[0027] In this embodiment, the outer diameter of the nozzle body 2 matches the inner diameter of the measuring pipe 1, that is, the portion between the outer side and the inner side of the nozzle body 2 is solid, which can ensure the self-strength of the nozzle body 2, thereby ensuring the ability of the nozzle body 2 to resist erosion and corrosion.

[0028] In this embodiment, the pressure taking position of the flow meter is upstream and downstream of the nozzle body 2, not at the throat 22, so there is no need to worry about the pressure-drawing hole being too large, thereby preventing the pressure from being poorly drawn. Compared with the Venturi flowmeter, it has a simple structure and low cost.

[0029] In this embodiment, the outlet of the throat 22 has no expanded diameter portion, and the fluid flows out in a jetting manner after passing through the throat 22, with a high streamline shape, thereby reducing the erosion and friction between the solids in the black and gray water and the inner wall of the measuring pipe 1.

[0030] To sum up, the flow meter disclosed in this embodiment meets the flow measurement requirements of black gray water and similar working conditions, has a long service life and wear and erosion resistance, and effectively solves the problems of low relative outflow coefficient, biased flow erosion, short service life, high cost of Venturi tube and small pressure port size of the wedge flow meter.

[0031] Example 2

[0032] Based on Example 1, a specific implementation method that can be implemented is further proposed.

[0033] A feasible implementation manner is that the nozzle body 2 is an integrated structural part, that is, the nozzle body 2 is made of an integral forging, and there is no connection point at the connection position between the throat 22 and the conical inlet section 21, thereby ensuring its own strength, thereby ensuring the ability of the nozzle body 2 to resist erosion and corrosion.

[0034] A feasible implementation manner is that the inner wall of the measuring pipe 1 and the inner wall of the nozzle body 2 are coated with a wear-resistant coating 3, and the wear-resistant coating 3 is a tungsten carbide coating, or a nickel-based alloy and tungsten carbide coating. The coating method can be high-temperature spraying to improve the wear resistance of the inner wall of the measuring pipe 1 and the inner wall of the nozzle body 2, thereby further improving the service life of the flow meter.

[0035] A feasible implementation manner is that the tapered inlet angle of the nozzle body 2 is 30°-90°; it is well known that the smaller the tapered inlet angle of the tapered inlet section 21, the more stable the flow measurement, which is beneficial to the measurement of fluid flow; however, if the tapered inlet angle of the nozzle body 2 is smaller, it will occupy a larger space, that is, the overall length of the nozzle body 2 is increased, and within the limited length of the measuring pipe 1 (if the length of the measuring pipe 1 is increased, it will lead to increased costs), the assembly position of other components in the flow meter body will be affected; therefore, the tapered inlet angle of the nozzle body 2 is preferably 60°.

[0036] In a feasible implementation manner, the length of the throat 22 is 0.3-0.5 times, preferably 0.3 times, the inner diameter of the throat 22 , so as to improve the streamline of the fluid after passing through the nozzle body 2 .

[0037] Example 3

[0038] Based on any one of the implementations in Examples 1-2, a feasible specific implementation is further proposed.

[0039] In a feasible implementation manner, the flow meter body also includes two pressure taking tubes 4, both of which are connected to the interior of the measuring pipeline 1, the position where the pressure taking tubes 4 are connected to the measuring pipeline 1 is a pressure taking port, and the nozzle body 2 is located between the two pressure taking tubes 4, which is used to obtain the fluid pressure in the measuring pipeline 1 upstream and downstream of the nozzle body 2.

[0040] Furthermore, the distance between the pressure taking position of the pressure taking tube 4 and the end of the nozzle body 2 is 1 / 3-1 / 2 of the inner diameter of the measuring pipe 1, preferably 1 / 2, which complies with industry standards and has a better pressure taking effect.

[0041] It should be noted that the pressure port size is based on the pressure flange size of the flow meter with different calibers and the matching differential pressure transmitter, and the commonly used ones are 32mm, 50mm, and 80mm.

[0042] In a feasible implementation manner, both pressure-taking tubes 4 are provided with a pressure-taking device 5 , and the pressure acquired by the pressure-taking device 5 is transmitted to a differential pressure transmitter 6 , thereby acquiring the fluid pressure difference in the measuring pipeline 1 at the upstream and downstream of the nozzle body 2 .

[0043] In a feasible implementation manner, a mounting base 7 is fixed on the outer wall of the measuring pipe 1, and the differential pressure transmitter 6 is assembled on the mounting base 7, so as to facilitate the integrated installation of the differential pressure transmitter on site and reduce the on-site installation process and procedures.

[0044] In a feasible implementation manner, both ends of the measuring pipeline 1 have connecting flanges 8 , and the measuring pipeline 1 can be connected to upstream and downstream pipelines conveying fluid through the connecting flanges 8 .

[0045] The present invention is not limited to the above-mentioned specific implementation modes, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A nozzle flow meter dedicated to black and gray water, characterized in that: The flow meter comprises a flow meter body, the flow meter body having a measuring pipe (1), an annular nozzle body (2) being fixed in the measuring pipe (1), the nozzle body (2) being composed of a conical inlet section (21) and a throat (22), the inner diameter of the throat (22) matching the minor diameter of the conical inlet section (21), and the throat (22) being fixedly connected to the conical inlet section (21); the inlet of the nozzle body (2) being located at the front end of the conical inlet section (21), and the outlet of the nozzle body (2) being located at the rear end of the throat (22); and the outer diameter of the nozzle body (2) matching the inner diameter of the measuring pipe (1).

2. The nozzle flow meter according to claim 1, characterized in that: The nozzle body (2) is an integrated structural component.

3. The nozzle flow meter according to claim 1, characterized in that: The inner wall of the measuring pipe (1) and the inner wall of the nozzle body (2) are both coated with a wear-resistant coating (3).

4. The nozzle flow meter according to claim 1, characterized in that: The cone inlet angle of the nozzle body (2) is 30°-90°.

5. The nozzle flow meter according to claim 1, characterized in that: The length of the throat (22) is 0.3-0.5 times the inner diameter of the throat (22).

6. The nozzle flow meter according to any one of claims 1 to 5, characterized in that: The flow meter body also includes two pressure-taking tubes (4), both of which are connected to the inside of the measuring pipeline (1), and the nozzle body (2) is located between the two pressure-taking tubes (4).

7. The nozzle flow meter according to claim 6, characterized in that: The distance between the pressure taking position of the pressure taking pipe (4) and the end of the nozzle body (2) is 1 / 3-1 / 2 of the inner diameter of the measuring pipe (1).

8. The nozzle flow meter according to claim 6, characterized in that: Both pressure-taking pipes (4) are provided with a pressure-taking device (5), and the pressure-taking device (5) is connected to a differential pressure transmitter (6).

9. The nozzle flow meter according to claim 8, characterized in that: A mounting base (7) is fixed on the outer wall of the measuring pipe (1), and the differential pressure transmitter (6) is mounted on the mounting base (7).

10. The nozzle flow meter according to claim 1, characterized in that: Both ends of the measuring pipe (1) are provided with connecting flanges (8).

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