Strain test method

Abstract

The present invention discloses a strain testing method, which relates to the field of strain testing technology, and specifically includes the following steps: S1, pasting a full-bridge strain gauge: connecting the two ends of a pump body to a water tank through a water pipe, and then pasting the full-bridge strain gauge on the surface of the pump shell; S2, connecting a strain gauge; S3, connecting a data collector; S4, voltage zeroing; S5, data acquisition; through the strain testing method of the present invention, it can be accurately concluded that when the speed of the pump is increased, the strain range of the pump body does not change much, so it can be concluded that the speed of the pump has no effect on the strain of the pump body during operation, and when the output pressure of the pump is increased, the strain of the pump body will increase, which also increases the burden on the pump body during operation. Therefore, through the strain testing method of the present invention, the optimal working state of the pump body can be accurately obtained, thereby ensuring the working efficiency of the pump body while extending the working life of the pump body.

Description

Technical Field

[0001] The present invention relates to the technical field of strain testing, and in particular to a strain testing method. Background Art

[0002] Strain gauges are components composed of sensitive grids and other components used to measure strain. The working principle of resistance strain gauges is based on the strain effect, that is, when a conductor or semiconductor material undergoes mechanical deformation under the action of an external force, its resistance value changes accordingly. This phenomenon is called the "strain effect." Generally, a strain gauge is made by attaching a sensitive grid (3μm-6μm) made of thin metal foil to a plastic film (15μm-16μm) called a substrate, and then covering it with a layer of film to form a laminated structure.

[0003] Existing strain tests use multi-point testing, and multiple full-bridge strain gauges need to be arranged during the strain test process. During the data collection process, due to the mutual errors between the multiple full-bridge strain gauges and the errors in the data obtained at different positions on the surface of the measured object, the data obtained during the strain test is inaccurate, which affects the analysis of the strain test results. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of the present invention is to provide a strain testing method. Through the strain testing method of the present invention, it can be accurately concluded that when the speed of the pump is increased, the strain range of the pump body does not change much. Therefore, it can be concluded that the speed of the pump has no effect on the strain of the pump body during operation. When the output pressure of the pump is increased, the strain of the pump body will increase, which will increase the burden on the pump body during operation. Therefore, through the strain testing method of the present invention, the optimal working state of pressure-bearing products or components such as the pump body, compressor cylinder or container can be accurately obtained, thereby ensuring the working efficiency of the pump body while extending the working life of the pump body, and multiple sets of data acquisition can be completed through a full-bridge strain gauge, which greatly increases the efficiency of the strain testing process.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] The strain testing method specifically includes the following steps:

[0007] S1. Paste the full-bridge strain gauge: Connect the two ends of the pump body to the water tank through water pipes, and then paste the full-bridge strain gauge on the surface of the pump housing;

[0008] S2. Connect the strain gauge: According to the type of full-bridge strain gauge and the connecting wire on the full-bridge strain gauge, connect the connecting wire to the corresponding position on the strain gauge. The principle of measuring strain of the strain gauge is as follows: Where K is the sensitivity coefficient of the full-bridge strain gauge;

[0009] S3. Connect the data collector: Connect the strain gauge to the data collector using a BNC adapter cable;

[0010] S4. Voltage zeroing: Turn on the power switch of the strain gauge, and the strain gauge will output a stable initial voltage, which is then zeroed.

[0011] S5. Data acquisition: By changing the pump speed and outlet pressure to obtain strain data under different working conditions, then use the formula The voltage signal output by the strain gauge is used to calculate the specific strain value, and the changes in the strain value under different speeds and pressures are analyzed, where με is the microstrain value to be measured, V0 is the output voltage signal, and V s is the bridge voltage input by the strain gauge, n is the number of useful bridge arms, K s is the instrument gain factor.

[0012] As a further solution of the present invention: the impeller inside the pump body is connected to the drive motor through a coupling.

[0013] As a further solution of the present invention: the data collector is connected to the PC via a data cable.

[0014] As a further solution of the present invention: a Wheatstone bridge is provided inside the strain gauge.

[0015] As a further solution of the present invention: the output end of the full-bridge strain gauge is provided with four connection ports, which are marked as 1, 2, 3 and 4 in sequence.

[0016] As a further solution of the present invention: five docking ports are provided on the front of the strain gauge, and the docking ports are marked as 1, 2, 3, 4 and 5 in sequence, among which docking ports 1, 2, 3 and 4 are respectively docked with connection ports 1, 2, 3 and 4 on the full-bridge strain gauge.

[0017] As a further solution of the present invention: the rotational speed of the pump body is set to 700 r / min, 800 r / min, 900 r / min and 1000 r / min respectively.

[0018] As a further solution of the present invention: the outlet pressure of the pump body is set to 20psi, 30psi, 40psi, 50psi and 60psi respectively.

[0019] As a further solution of the present invention: S1 further includes the following steps:

[0020] Y1: Select a point at the center of the pump casing and mark it;

[0021] Y2: Use sandpaper to polish the selected shell surface to remove the oxide layer, and then clean the surface with industrial tissue paper;

[0022] Y3: Place a drop of adhesive on the back of the strain gauge, then immediately stick the strain gauge on the marked position and press it. After the pressurization is completed, it can be fixed again with insulating tape.

[0023] Beneficial effects of the present invention: Through the strain testing method of the present invention, it can be accurately concluded that when the pump speed is increased, the strain range of the pump body does not change much. Therefore, it can be concluded that the pump speed has no effect on the strain of the pump body during operation. When the pump output pressure is increased, the strain of the pump body will increase, which will increase the burden on the pump body during operation. Therefore, through the strain testing method of the present invention, the optimal working state of the pump body can be accurately obtained, thereby ensuring the working efficiency of the pump body while extending the working life of the pump body. The strain testing method can achieve the same technical effect for products or components that bear pressure, such as compressor cylinders and containers. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described below with reference to the accompanying drawings.

[0025] Figure 1 This is the equipment connection diagram of the present invention

[0026] Figure 2 Schematic diagram of the structure of the full-bridge strain gauge in the present invention;

[0027] Figure 3 is a top view of the strain gauge of the present invention;

[0028] Figure 4 It is a circuit diagram of the Wheatstone bridge in the present invention. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] like Figure 1-Figure 4 As shown, the strain testing method specifically includes the following steps:

[0031] S1. Paste the full-bridge strain gauge: Connect the two ends of the pump body to the water tank through water pipes, and then paste the full-bridge strain gauge on the surface of the pump housing. Specifically:

[0032] Y1: Select a point at the center of the pump casing and mark it;

[0033] Y2: Use sandpaper to polish the selected shell surface to remove the oxide layer, and then clean the surface with industrial tissue paper;

[0034] Y3: Put a drop of adhesive on the back of the strain gauge, then immediately stick the strain gauge on the marked position and press it. After the pressurization is completed, fix it again with insulating tape.

[0035] S2. Connect the strain gauge: According to the type of full-bridge strain gauge and the connecting wire on the full-bridge strain gauge, connect the connecting wire to the corresponding position on the strain gauge. The principle of measuring strain of the strain gauge is as follows: Where K is the sensitivity coefficient of the full-bridge strain gauge;

[0036] S3. Connect the data collector: Connect the strain gauge to the data collector using a BNC adapter cable;

[0037] S4. Voltage zeroing: Turn on the power switch of the strain gauge, and the strain gauge will output a stable initial voltage, which is then zeroed.

[0038] S5. Data acquisition: By changing the pump speed and outlet pressure to obtain strain data under different working conditions, then use the formula The voltage signal output by the strain gauge is used to calculate the specific strain value, and the changes in the strain value under different speeds and pressures are analyzed, where με is the microstrain value to be measured, V0 is the output voltage signal, and V s is the bridge voltage input by the strain gauge, n is the number of useful bridge arms, K s is the instrument gain factor.

[0039] The impeller inside the pump body is connected to the drive motor through a coupling.

[0040] The data collector is connected to the PC via a data cable.

[0041] A Wheatstone bridge is set inside the strain gauge.

[0042] The output end of the full-bridge strain gauge is provided with four connection ports, which are marked as 1, 2, 3 and 4 in sequence.

[0043] There are five docking ports on the front of the strain gauge, which are marked as 1, 2, 3, 4 and 5 in sequence. The docking ports 1, 2, 3 and 4 are connected to the connection ports 1, 2, 3 and 4 on the full-bridge strain gauge respectively.

[0044] The rotation speeds of the pump body are set to 700r / min, 800r / min, 900r / min and 1000r / min respectively.

[0045] The outlet pressure of the pump body is set to 20psi, 30psi, 40psi, 50psi and 60psi respectively;

[0046] The above 20 groups of data are converted into The specific strain value is calculated from the voltage signal output by the strain gauge, and the changes in the strain value under different speeds and pressures are analyzed to obtain the data in the following table:

[0047] 700r / min 800r / min 900r / min 1000r / min 20psi 34 35 36 37 30psi 43 40 42 43 40psi 50 49 50 50 50psi 57 56 59 58 60psi 64 65 66 67

[0048] According to the data in the above table, when the pump speed is increased, the strain range of the pump body does not change much. Therefore, it can be concluded that the pump speed has no effect on the strain of the pump body during operation. When the pump output pressure is increased, the strain of the pump body will increase, which will increase the burden on the pump body during operation. Therefore, through the strain testing method of the present invention, the optimal working state of the pump body can be accurately obtained, thereby ensuring the working efficiency of the pump body while extending the working life of the pump body. The strain testing method of the present invention can achieve the same technical effect for products or components that bear pressure, such as compressor cylinders and containers.

[0049] The above is a detailed description of an embodiment of the present invention. However, the content described is only a preferred embodiment of the present invention and should not be considered to limit the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A strain testing method, characterized in that: The test method includes the following steps: S1. Paste the full-bridge strain gauge: Connect the two ends of the pump body to the water tank through water pipes, and then paste the full-bridge strain gauge on the surface of the pump housing; S2. Connect the strain gauge: According to the type of full-bridge strain gauge and the connecting wire on the full-bridge strain gauge, connect the connecting wire to the corresponding position on the strain gauge. The principle of measuring strain of the strain gauge is as follows: Where K is the sensitivity coefficient of the full-bridge strain gauge; S3. Connect the data collector: Connect the strain gauge to the data collector using a BNC adapter cable; S4. Voltage zeroing: Turn on the power switch of the strain gauge, and the strain gauge will output a stable initial voltage, which is then zeroed. S5. Data acquisition: By changing the pump speed and outlet pressure to obtain strain data under different working conditions, then use the formula The voltage signal output by the strain gauge is used to calculate the specific strain value, and the changes in the strain value under different speeds and pressures are analyzed, where με is the microstrain value to be measured, V0 is the output voltage signal, and V s is the bridge voltage input by the strain gauge, n is the number of useful bridge arms, K s is the instrument gain factor.

2. The strain testing method according to claim 1, characterized in that: The impeller inside the pump body is connected to a driving motor through a coupling.

3. The strain testing method according to claim 1, wherein: The data collector is connected to the PC via a data cable.

4. The strain testing method according to claim 1, wherein: A Wheatstone bridge is provided inside the strain gauge.

5. The strain testing method according to claim 1, wherein: The output end of the full-bridge strain gauge is provided with four connection ports, which are marked as 1, 2, 3 and 4 in sequence.

6. The strain testing method according to claim 5, characterized in that: The strain gauge is provided with five docking ports on the front side, which are marked as 1, 2, 3, 4 and 5 in sequence, wherein docking ports 1, 2, 3 and 4 are docked with connection ports 1, 2, 3 and 4 on the full-bridge strain gauge respectively.

7. The strain testing method according to claim 1, characterized in that: The rotation speed of the pump body is set between 700r / min and 1000r / min.

8. The strain testing method according to claim 1, wherein: The outlet pressure of the pump body is set between 20 psi and 60 psi.

9. The strain testing method according to claim 1, characterized in that: The S1 also The following steps are involved: Y1: Select a point at the center of the pump casing and mark it; Y2: Use sandpaper to polish the selected shell surface to remove the oxide layer, and then clean the surface with industrial tissue paper; Y3: Place a drop of adhesive on the back of the strain gauge, then immediately stick the strain gauge on the marked position and press it. After the pressurization is completed, it can be fixed again with insulating tape.

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