Valve piston sealing performance quantitative evaluation tool

Abstract

The utility model discloses a quantitative evaluation tool for the sealing performance of a valve piston. The quantitative evaluation tool comprises an air source, a pressure reducing valve, a pressure regulator, a flow limiter inlet pressure gauge, a flow limiter, a flow limiter outlet pressure gauge and a butt joint which are sequentially connected to a pipeline in the flowing direction of an air path. The butt joint is in butt joint with the cavity of the valve piston to be evaluated. A contraction micropore is formed in the inner cavity of the flow limiter, so that a trumpet-shaped contraction cavity and a trumpet-shaped expansion cavity are respectively formed in the inner cavity of the flow limiter on the two sides of the contraction micropore. A pressure reducing valve inlet pressure gauge is arranged on an inlet of the pressure reducing valve and connected with an air source. A pressure reducing valve outlet pressure gauge is arranged on an outlet of the pressure reducing valve and connected with the pressure regulator. A pressure release valve is connected between the pressure regulator and the flow limiter inlet pressure gauge in a bypass mode. According to the tool, the valve with degraded performance can be quantitatively evaluated before the valve piston fails, an airline can accurately implement preventive maintenance according to evaluation data, the cost is reduced, and the effect is improved.

Description

Technical Field

[0001] This utility model relates to the field of aircraft ground maintenance technology, and in particular to a tool for quantitatively evaluating the sealing performance of a valve piston. Background Technology

[0002] Civil aircraft are equipped with numerous piston-controlled pneumatic valves. The opening and closing of these valves control the normal operation of systems such as bleed air, air conditioning, anti-icing, and engine starting. In practical applications, valve failure can sometimes occur due to piston sealing malfunctions (such as leakage or jamming). Leakage can lead to insufficient servo airflow thrust, while jamming can cause excessive piston actuation resistance. Both leakage and jamming can prevent the valve from operating normally, resulting in valve failure, which in turn causes the triggering system to malfunction and affects the safe and normal operation of the flight.

[0003] Currently, to avoid such situations, the valve needs to be periodically removed and sent to a parts repair shop for preventative maintenance. However, this type of maintenance has the following drawbacks:

[0004] 1. The lack of quantitative assessment of the impact of valve piston sealing performance degradation means that inspections can only be carried out periodically, which is inefficient and affects normal operation.

[0005] 2. Sending items for repair is costly, and items that don't yet meet the criteria for external repair are also sent for inspection, resulting in poor targeting. Utility Model Content

[0006] To address the shortcomings of existing technologies, this invention provides a tool for quantitatively evaluating the sealing performance of valve pistons, thereby overcoming the deficiencies in existing technologies.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A tool for quantitatively evaluating the sealing performance of a valve piston includes a gas source, a pressure reducing valve, a pressure regulator, a flow restrictor inlet pressure gauge, a flow restrictor, a flow restrictor outlet pressure gauge, and a connector, which are connected sequentially along the gas flow direction on the pipeline.

[0009] The connector is connected to the cavity of the valve piston for receiving evaluation;

[0010] The flow limiter has an axially arranged shrinkage micropore in its inner cavity.

[0011] Furthermore, a pressure gauge is installed on the inlet of the pressure reducing valve, and the pressure gauge is connected to a gas source.

[0012] Furthermore, a pressure gauge is provided at the outlet of the pressure reducing valve, and the pressure gauge is connected to a pressure regulator.

[0013] Furthermore, a pressure relief valve is also connected between the pressure regulator and the inlet pressure gauge of the flow limiter.

[0014] Preferably, the gas source is an aviation nitrogen cylinder.

[0015] Preferably, the shrinkage micro-orifice causes the inner cavity of the flow limiter to form a trumpet-shaped shrinkage cavity and a trumpet-shaped expansion cavity on both sides of the shrinkage micro-orifice.

[0016] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0017] 1) The valve piston sealing performance quantitative assessment tool in this case utilizes Bernoulli's principle of the flow limiter to quantitatively assess the performance degradation of valves before valve failure. Airlines can accurately implement preventive maintenance based on the assessment data, thereby reducing costs and improving effectiveness.

[0018] 2) The valve piston sealing performance quantitative evaluation tool in this case has a pressure reducing valve and a pressure regulator installed between the air source (1) and the flow restrictor. The pressure is roughly adjusted by the pressure reducing valve and the pressure is precisely adjusted to the required pressure by the pressure regulator to ensure the stability and reliability of the measurement and evaluation.

[0019] To provide a clearer understanding of this invention, the preferred embodiments of this invention will be described below in conjunction with the accompanying drawings. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of this utility model.

[0021] Attached image labels:

[0022] 1-Gas source, 2-Pressure regulator inlet gauge, 3-Pressure regulator, 4-Pressure regulator outlet gauge, 5-Pressure regulator, 6-Pressure relief valve, 7-Flow restrictor inlet gauge, 8-Flow restrictor, 9-Flow restrictor outlet gauge, 10-Connecting connector, 11-Valve piston, 12-Seal. Detailed Implementation

[0023] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and 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, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0024] Furthermore, if terms such as "first" or "second" are used for descriptive purposes only, they are mainly used to distinguish different devices, components or parts (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance or quantity of the indicated devices, components or parts, and should not be construed as indicating or implying relative importance.

[0025] Furthermore, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0026] Please also refer to Figure 1 This utility model provides a tool for quantitatively evaluating the sealing performance of a valve piston, comprising an air source 1, a pressure reducing valve 3, a pressure regulator 5, a flow restrictor inlet pressure gauge 7, a flow restrictor 8, a flow restrictor outlet pressure gauge 9, and a connector 10 connected sequentially along the air flow direction on the pipeline; the connector 10 is used to connect to the cavity of the valve piston 11 to be evaluated; the flow restrictor 8 is a flow restrictor that works using Bernoulli's principle, and the inner cavity of the flow restrictor 8 has an axially arranged contraction micro-orifice [not shown in the figure], so that the inner cavity of the flow restrictor 8 forms a trumpet-shaped contraction cavity and a trumpet-shaped expansion cavity on both sides of the contraction micro-orifice.

[0027] Preferably, in this embodiment, a pressure gauge 2 is provided on the inlet of the pressure reducing valve 3, and the pressure gauge 2 is connected to the air source 1; a pressure gauge 4 is provided on the outlet of the pressure reducing valve 3, and the pressure gauge 4 is connected to the pressure regulator 5.

[0028] As a preferred embodiment, in this embodiment, a pressure relief valve 6 is also connected between the pressure regulator 5 and the inlet pressure gauge 7 of the flow limiter. The pressure relief valve 6 is used to release the pipeline pressure after the test is completed.

[0029] Preferably, in this embodiment, the gas source 1 is an aviation nitrogen cylinder.

[0030] The working principle of current limiter 8 is as follows:

[0031] The inner cavity of the flow restrictor 8 has a contraction micro-orifice, which forms a horn-shaped contraction cavity and a horn-shaped expansion cavity on both sides of the contraction micro-orifice. When the seal 12 of the valve piston 11 at the end of the tool leaks, the airflow is in a flowing state. When the airflow flows through the horn-shaped contraction cavity of the flow restrictor 8, the cross-section gradually shrinks linearly. According to the principle of continuity, the flow velocity increases and the kinetic energy rises. According to Bernoulli's principle, the static pressure decreases. When the airflow flows through the horn-shaped expansion cavity of the flow restrictor 8, the cross-section increases, the flow velocity decreases, the kinetic energy decreases, and the static pressure rises. However, because the seal (12) relieves part of the pressure, the static pressure cannot be completely restored to the upstream pressure value of the flow restrictor.

[0032] Therefore, when the seal 12 of the valve piston 11 leaks, the pressure at the rear end of the flow restrictor 8 is less than the pressure at the front end of the flow restrictor 8.

[0033] When there is no leakage at the seal 12 of the valve piston 11, the fluid is in a non-flowing state, the static pressure before and after the contraction micro-orifice is the same, and the pressure at the front and rear ends of the flow restrictor 8 is the same.

[0034] The working principle or operating procedure of the valve piston sealing performance quantitative evaluation tool in this case is as follows:

[0035] 1. The front end of the tool is connected to the air source 1, and the rear end is connected to the cavity of the valve piston 11 to be evaluated;

[0036] 2. The pressure of the gas source 1 is roughly adjusted by the pressure reducing valve 3, and the pressure is precisely adjusted to the required pressure by the pressure regulator 5;

[0037] 3. If the sealing 12 of the valve piston 11 at the end does not leak after the airflow passes through the flow restrictor 8, then the readings of the pressure gauge 7 at the inlet of the flow restrictor and the pressure gauge 9 at the outlet of the flow restrictor will be the same.

[0038] 4. If there is air leakage in the seal 12 of the valve piston 11 at the end, the reading of the pressure gauge 9 at the outlet of the flow restrictor will be less than the reading of the pressure gauge 7 at the inlet of the flow restrictor. By comparing the readings of the pressure gauge 7 at the inlet of the flow restrictor and the pressure gauge 9 at the outlet of the flow restrictor, the leakage of the seal 12 of the valve piston 11 can be quantitatively assessed.

[0039] 5. At the same time, the outlet pressure of the flow restrictor 8 can be slowly increased from low to high, and the value of the flow restrictor outlet pressure gauge 9 can be recorded when the valve piston 11 goes from rest to actuation. The larger the value of the flow restrictor outlet pressure gauge 9, the more serious the valve piston 11 is stuck. Thus, the stuck condition of the valve piston 11 can be quantitatively evaluated.

[0040] Compared to existing technologies, the valve piston sealing performance quantitative assessment tool in this case can quantitatively assess the performance degradation of valves before valve failure. Airlines can then accurately implement preventative maintenance based on the assessment data, reducing costs and improving effectiveness.

[0041] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these modifications and improvements all fall within the protection scope of this utility model.

Claims

1. A tool for quantitatively evaluating the sealing performance of a valve piston, characterized in that: It includes a gas source (1), a pressure reducing valve (3), a pressure regulator (5), a flow restrictor inlet pressure gauge (7), a flow restrictor (8), a flow restrictor outlet pressure gauge (9), and a connector (10) connected sequentially along the gas flow direction on the pipeline. The connector (10) is connected to the cavity of the valve piston (11) for receiving evaluation; The flow limiter (8) has an axially arranged shrinkage micropore in its inner cavity.

2. The valve piston sealing performance quantitative evaluation tool according to claim 1, characterized in that: The pressure reducing valve (3) is equipped with a pressure reducing valve inlet gauge (2), which is connected to the gas source (1).

3. The valve piston sealing performance quantitative evaluation tool according to claim 2, characterized in that: The outlet of the pressure reducing valve (3) is provided with a pressure reducing valve outlet pressure gauge (4), which is connected to a pressure regulator (5).

4. The valve piston sealing performance quantitative evaluation tool according to claim 3, characterized in that: A pressure relief valve (6) is also connected between the pressure regulator (5) and the inlet pressure gauge (7) of the flow limiter.

5. The valve piston sealing performance quantitative evaluation tool according to claim 4, characterized in that: The gas source (1) is an aviation nitrogen cylinder.

6. The valve piston sealing performance quantitative evaluation tool according to claim 5, characterized in that: The shrinkage micro-orifice causes the inner cavity of the flow limiter (8) to form a trumpet-shaped shrinkage cavity and a trumpet-shaped expansion cavity on both sides of the shrinkage micro-orifice.

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