CN101403668B - Bulk modulus measuring device and testing method for solid buoyant material - Google Patents

Abstract

The invention provides a measuring device used for measuring the volume elastic modulus of a solid buoyant material. The measuring device comprises a bearing device, a pressure-regulating deice and a measurement control device. The bearing device comprises a hydraulic cylinder and a hydraulic cylinder cover; a pressure meter and a pressure-regulating valve are arranged on the upper part of the hydraulic cylinder cover; the pressure-regulating device comprises a hydraulic pump and a corresponding plunger; the lower end of the hydraulic pump is communicated with a water supply; the upper end of the plunger is connected with a motor; the measurement control device comprises a programmable controller, a pressure sensor and a linear scale; the pressure sensor and the pressure meter are arranged on a pipeline communicating the hydraulic cylinder and the hydraulic pump; the finger of the linear scale and the plunger moves synchronously; and the pressure sensor, linear scale and motor all can be controlled by the programmable controller. The invention also discloses a test method used for solving the problem in the prior art that the volume elastic modulus cannot be measured. The invention is provided with the guidance for the study of solid buoyant material.

Description

Bulk modulus measuring device and testing method for solid buoyant material

technical field

The invention relates to a hydrostatic pressure simulation device for detecting the bulk elastic modulus of solid buoyant materials, in particular to a measuring device and a testing method for measuring the bulk elastic modulus of solid buoyant materials for deep sea operations.

Background technique

Solid buoyancy material is an important part of the development of modern deep diving technology. The material can withstand huge hydrostatic pressure thousands of meters underwater, and its own density is only about half that of water. It can provide buoyancy to support the weight of the robot and the material itself. When the mechanical power stops or an accident occurs such as the umbilical cable breaks, it can ensure that the submersible will automatically float up, so that the submersible will not be lost, so as to ensure the safety of life and property. Solid buoyancy materials can solve the pressure resistance and structural stability of manned deep submersibles, provide sufficient net buoyancy, increase the payload of the submersible, and reduce its overall size, especially in the construction of large-depth manned submersibles. has an important role.

my country is located in the Asian continent, facing the Pacific Ocean, and has a coastline of 18,000 kilometers. In addition, there is a sea area of 75,000 square kilometers in the Pacific Ocean, which contains a lot of valuable wealth, especially in water depths below 5,000 meters. The resources available for research and development are very rich. All underwater operations need to rely on underwater robots, and the floating of underwater robots is inseparable from deep-sea solid buoyancy materials.

In the research process of solid buoyant materials, the bulk modulus of solid buoyant materials is a key index to measure the volume change of the material under the action of underwater high pressure, and the smaller volume directly leads to the loss of buoyancy.

Contents of the invention

The invention provides a solid buoyant material volume elastic modulus measurement device and a test method, which can solve the problems in the prior art that the detection efficiency of the solid buoyant material is not high and the volume elastic modulus cannot be measured.

In order to solve the above-mentioned technical problems, the present invention adopts the following technical solutions to achieve:

A device for measuring bulk modulus of elasticity of a solid buoyant material, said measuring device comprising a bearing device, a pressure regulating device and a measurement control device,

The carrying device includes a hydraulic cylinder and a hydraulic cylinder cover, and a pressure gauge and a pressure regulating valve are arranged on the upper part of the hydraulic cylinder cover;

The pressure regulating device includes a hydraulic pump and its plunger, the lower end of the hydraulic pump is connected to a water source, and the upper end of the plunger is connected to a motor;

The measurement control device includes a programmable controller, a pressure sensor and a grating ruler, and the pressure sensor and the pressure gauge are all arranged on the pipeline connecting the hydraulic cylinder and the hydraulic pump, and the pointer of the grating ruler is connected to the column The plug moves synchronously, and the pressure sensor, grating scale and motor are all controlled by the programmable controller.

In the technical solution of the present invention, it also has the following technical features: the pressure regulating valve is a pressurization valve and a pressure relief valve, and is arranged on the pipeline and located on both sides of the pressure gauge.

In the technical solution of the present invention, it also has the following technical features: the inner diameter of the hydraulic cylinder is 60-350mm, and the outer diameter is 120-550mm.

In the technical solution of the present invention, it also has the following technical features: the upper end of the plunger is provided with a plunger rod, the plunger is connected with the motor through the plunger rod, and the pointer of the grating scale is set on the on the plunger rod.

In the technical solution of the present invention, it also has the following technical features: a calibration steel block is preset in the inner cabin of the hydraulic cylinder, and the volume of the calibration steel block is equal to the volume of the solid buoyancy material to be measured.

In the technical solution of the present invention, it also has the following technical features: the motor is a servo motor.

In the technical solution of the present invention, it also has the following technical features: the measuring device also includes a supporting device, and the supporting device includes a hydraulic cylinder supporting device and a hydraulic pump supporting device, wherein the hydraulic cylinder supporting device includes a first bracket. The upper end of a support is provided with a rotary lifting device for lifting the hydraulic cylinder cover, hydraulic cylinder struts are provided on both sides of the hydraulic cylinder, and a rotary bearing is provided on the first support, and the hydraulic cylinder passes through the hydraulic cylinder struts. connected to the rotating bearing and then supported on the first support; the hydraulic pump supporting device includes a second support for supporting the hydraulic pump, and the motor is installed on the upper part of the second support.

The method and test process for measuring the bulk modulus of solid buoyancy materials, the method used is the volume displacement method.

A test method for measuring the bulk modulus of solid buoyancy materials, comprising the steps of:

(a) First put a calibration steel block in the inner compartment of the hydraulic cylinder;

(b) Open the pressurization valve and pressure relief valve, and then connect the lower end of the hydraulic pump to the water source. After the system is filled with water, water will flow out of the pressure relief valve. At this time, close the pressure relief valve;

(c) After the pre-pressure is set by the programmable controller, start the servo motor, pull the plunger to move through the plunger rod, the water in the inner cavity of the hydraulic pump is squeezed by the plunger to generate pressure, and through the connection The size of the pipeline will transmit the pressure to the inner chamber of the hydraulic cylinder, and the pressure will act on the sample to be tested at the same time. The internal pressure of the system will be measured by the pressure sensor, and the measured data will be sent to the programmable controller. Compare the measured data with the set pressure value, if the pressure is not reached, control the rotation of the servo motor, and continue to apply pressure until the pressure reaches the set value;

(d) The displacement of the plunger is measured by the grating ruler, and the measurement data is automatically recorded on the computer through the programmable controller, and the computer simultaneously calculates the volume change of the water caused by the displacement of the plunger;

(e) Through the above two steps (c) and (d), the volume change of the system under a pressure can be obtained, and this data is calibrated as a reference value;

(f) Measure the volume change under a series of pressures and calibrate them as reference values under corresponding pressures;

(g) After taking out the steel block, put the solid buoyancy material sample to be tested into the hydraulic cylinder, and add water;

(h) Pressurize the water together with the solid buoyancy material to be tested to the set static pressure, the plunger is lowered, the set static pressure is determined according to the water depth that the buoyancy material can serve within the working range of the device, and then repeat the steps ( as described in d).

In the technical solution of the present invention, it also has the following technical features: the moving speed of the plunger is 0.1-10mm/min.

In the technical solution of the present invention, it also has the following technical features: the pre-pressure set by the programmable controller is 0.1-70 MPa.

The calculation method for calculating the bulk modulus of the solid buoyant material sample according to the above-mentioned measurement method and measurement device is as follows:

(a) The volume change of the solid buoyant material sample is: the compression amount of water and the sample minus the water compression amount, and the water compression amount is the volume change amount when the calibration steel block is put into it. This data has been mentioned above ( e) Calibrated as the reference value during the process.

(b) Correct the water absorption of the sample as follows, and weigh the weight of the sample before and after compression. The added weight is converted to volume and subtracted from the actual ΔVc below.

(c) The relationship between the volume change of water and the volume change of the sample is shown in the following formula:

Compression ratio:

$\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;\; Vs</span>}}{\mathrm{<span\; class="notranslate">\; vs.</span>}}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;Vc</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&Delta;\; Vw</span>}}{\mathrm{<span\; class="notranslate">\; vs.</span>}}<span\; class="notranslate">\; )</span>$

Where: K = compression ratio

ΔP = pressure change

ΔVs = volume change of the sample (corrected for water absorption)

ΔVc = total volume change of sample and inhaled water

ΔVw = volume change of inhaled water

Vs = initial volume of sample

Bulk modulus: ${\mathrm{E.}}_B=\frac{-\mathrm{\&Delta;P}}{\mathrm{\&Delta;\; Vs}}\&times;\mathrm{vs.}=\frac{\mathrm{\&Delta;P}}{K}.$

Bulk modulus test device control system:

The entire test process is automatically controlled by the computer, and any pressure curve can be set to adjust the pressure in the hydraulic cylinder cabin according to the requirements. All test settings and operations can be completed on the automatic console, and the computer automatically generates pressure, time curves and volume changes. , time curve, and store various data, and the test report can be printed out at any time. The specific control system is shown in Figure 2.

The signal transmission and conversion work of the system is completed by a programmable controller. After setting the pressure level with the computer, the programmable controller transmits the work instruction to the servo motor, and the servo motor pulls the plunger through the plunger rod to make a displacement. The displacement of the plunger causes the pressure to change, and the pressure situation is transmitted back to the programmable controller through the pressure sensor, and then fed back to the computer, which draws the curve of the pressure change with time.

The displacement change is measured by a grating ruler, and the grating ruler transmits the displacement data to the programmable controller, which is then transmitted to the computer. The computer calculates the volume change and then generates the volume change curve with time.

In addition, the pressure supply and supplementary pressure operations can also be completed through the programmable controller alone. The operation is very convenient and does not require computer control.

Compared with prior art, advantage and positive effect of the present invention are:

The invention studies the bulk elastic modulus and testing method of the solid buoyancy material. Developed the bulk modulus measurement device; designed and formulated the test method for the bulk compression modulus; introduced the calculation formula of the solid buoyancy material bulk modulus; and installed an automatic control device for the bulk modulus detection device, making the detection process more efficient Convenience, more accurate test data, and stronger traceability of test results.

The invention has guiding significance for the research of solid buoyancy materials, and has an important reference function for the process of designing and manufacturing submersibles of buoyancy material application units.

Description of drawings

Fig. 1 is the principle schematic diagram of bulk modulus measuring device of solid buoyancy material;

Fig. 2 is the control system figure of bulk modulus measuring device;

Fig. 3 is the concrete test system assembly schematic diagram of bulk elastic modulus measuring device;

Among them: 10. Bearing device; 11. Hydraulic cylinder; 12. Hydraulic cylinder cover; 13. Pressure gauge; 14. Pressure valve; 15. Pressure relief valve; 16. Hydraulic cylinder inner cabin; 17. Calibration steel block; 18. piping;

20. Pressure regulating device; 21. Hydraulic pump; 22. Plunger; 23. Inner cavity of hydraulic pump; 24. Plunger rod; 25. Tap water switch; 26. Servo motor;

30. Measurement control device; 31. Pressure sensor; 32. Grating ruler; 33. Pointer;

40. Supporting device; 41. Rotary lifting device; 42. First bracket; 43. Hydraulic cylinder rod; 44. Rotary bearing; 45. Second bracket; 46. Water tank; 47. Drainage pipeline.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the solid buoyancy material bulk modulus testing device of the present invention is mainly made of three parts: carrying device 10, pressure regulating device 20 and measurement control device 30,

The carrying device 10 includes a hydraulic cylinder 11 and its hydraulic cylinder cover 12, a pressure gauge 13 is arranged on the upper part of the hydraulic cylinder cover 12, and a pressurizing valve 14 and a pressure relief valve 15 are respectively arranged on the left and right sides of the pressure gauge 13; A calibration steel block 17 is preset, and the volume of the calibration steel block 17 is equal to the volume of the solid buoyancy material to be tested.

The pressure regulating device 20 includes a hydraulic pump 21 and its plunger 22, the lower end of the hydraulic pump 21 is connected to a tap water switch 25, the upper end of the plunger 22 is provided with a plunger rod 24, and the plunger rod 24 is connected to a servo motor 26;

The measurement control device 30 includes a programmable controller (not shown in the figure), a pressure sensor 31 and a grating scale 32. The pressure sensor 31 and the pressure gauge 13 are all arranged on the pressure-resistant pipeline 18, and the pressure-resistant pipeline 18 communicates with the hydraulic pressure. cylinder 11 and hydraulic pump 21, the pointer of the grating ruler 32 is arranged on the plunger rod 24, that is, the pointer 33 of the grating ruler 32 moves synchronously with the plunger 22, the pressure sensor 31, the grating ruler 32 and servo motor 26 are all controlled by the programmable controller.

As shown in Figure 3, the specific test system assembly schematic diagram of the bulk modulus of elasticity measurement device,

Since the actual maximum working pressure of the bulk modulus test system in the present invention is 87.5MP, the hydraulic cylinder in the test system must be designed with a thicker metal outer wall. Considering its heavy weight and frequent disassembly, the measuring device also includes a supporting device 40. In the present invention, a rotating lifting device 41 is designed on the hydraulic cylinder cover 12 to make opening the hydraulic cylinder cover 12 more convenient. The rotating lifting device 41 is installed directly above the hydraulic cylinder head 12 and is supported by a first bracket 42 made of metal. Equally considering that the weight is bigger, in the present invention, swivel bearing 44 is installed on both sides of hydraulic cylinder 11, and the both sides of hydraulic cylinder is provided with hydraulic cylinder strut 43, is provided with swivel bearing 44 on the first support, and hydraulic cylinder 11 passes through The hydraulic cylinder strut 43 is connected to the rotary bearing 44 and then supported on the first support 42;

When the equipment is not in use, the water therein can be easily poured out into the water tank 46, and the water is drained through the drainage pipeline 47, which is beneficial for preventing the system from being corroded and damaged.

The hydraulic pump 21 is supported on the second bracket 45 , and the servo motor 26 is installed on the upper part of the second bracket 45 . The plunger rod 24 moves up and down under the drive of the servo motor 26, and the plunger 22 is connected with the plunger rod 24 to move up and down together. The outer wall of the hydraulic pump 21 is fixed on the bottom of the second bracket 45 and cannot move, so the plunger 22 will squeeze the water in the inner cavity 23 of the hydraulic pump to generate pressure, and the pressure can be transmitted to the system through the connecting pipeline 18 without change. various parts of the interior. The magnitude of the applied pressure can be adjusted by controlling the servo motor 26 and further controlling the displacement of the plunger 22 .

The specific test method steps are as follows:

1. Working parameters:

Working pressure: the maximum is 70MPa, the safety factor is 1.25, and the actual maximum working pressure is 87.5MPa;

Working medium: water;

The moving speed of the plunger is 1.5mm/min;

Hydraulic cylinder inner diameter = 60-350mm;

Hydraulic cylinder outer diameter = 120-550mm;

Plunger seal: Nitrile rubber "O" ring (with PTFE bracket);

2. Test sample:

The size of the test sample is 100×40×40 mm (160 ml).

3. Test process:

(a) A calibration steel block 17 is placed in the inner cabin 16 of the hydraulic cylinder, and the size is 100×40×40mm (160ml);

(b) Open the pressurization valve 14 and the pressure relief valve 15. Now the pressure relief valve 15 is used as the exhaust port, and then open the tap water switch 25. After the system is filled with water, the pressure relief valve 15 will have water to flow out. Now close pressure relief valve 15;

(c) After the pressure of 70 MPa is set by the programmable controller, the servo motor 26 is started, and the plunger 22 is pulled by the plunger rod 24 to move. The water in the hydraulic pump inner cavity 23 is squeezed by the plunger 22 to generate pressure, and the pressure is transmitted to the hydraulic cylinder inner compartment 16 through the connecting pipeline 18 in a constant size. This pressure acts simultaneously on the sample to be tested. The pressure inside the system is measured by the pressure sensor 31, and the measurement data is sent to the programmable controller. The programmable controller compares the measured data with the set pressure value, and if the pressure is not reached, it controls the rotation of the servo motor 26 and continues to apply pressure until the pressure reaches the set value;

(d) The moving speed of the plunger 22 is 1.5mm/min, the displacement of the plunger 22 is measured by the grating ruler 32, and the measurement data is automatically recorded on the computer through the programmable controller. The computer simultaneously calculates the volume change of the water due to the displacement of the plunger;

(e) Through the above two steps (c) and (d), the volume change of the system under a pressure can be obtained, and this data is calibrated as a reference value;

(f) Measure the volume change under a series of pressures and calibrate them as reference values under corresponding pressures;

(g) After taking out the steel block, put the solid buoyancy material sample to be tested into the hydraulic cylinder, and add water;

(h) Pressurize the water together with the solid buoyancy material to be tested to the set static pressure, the plunger is lowered, the set static pressure is determined according to the water depth that the buoyancy material can serve within the working range of the device, and then repeat the steps ( as described in d).

In the present invention, the testing device of bulk elastic modulus is designed; The test method and test steps of bulk elastic modulus are formulated; The calculation formula of bulk elastic modulus of solid buoyancy material is deduced; The automatic control system is introduced to make the testing process more intuitive , the test result is more accurate; in addition, the present invention considers the practicability of the device, and innovates in the assembly of the mechanical device. The invention can improve the detection efficiency and reduce the number of experiments in the research and development process of the solid buoyancy material. It has important guiding significance for the research of solid buoyant materials. It is an important reference for the design and manufacture of submersibles for solid buoyancy material application units.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention to other forms. Any skilled person who is familiar with this profession may use the technical content disclosed above to change or modify the equivalent of equivalent changes. Example. However, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still belong to the protection scope of the technical solution of the present invention.

Claims (7)

1. volume elastic modulus of solid buoyancy material measurement mechanism, it is characterized in that: described measurement mechanism comprises bogey, regulator and measuring and controlling,

Described bogey comprises a hydraulic cylinder and hydraulic cylinder, is provided with tensimeter and pressure regulating valve on hydraulic cylinder top;

Described regulator comprises a hydraulic pump and plunger thereof, and the hydraulic pump lower end is communicated with the water source, and the upper end of described plunger connects servomotor;

Described measuring and controlling comprises programmable controller, pressure transducer and grating chi, described pressure transducer and tensimeter all are arranged on the pipeline that is communicated with described hydraulic cylinder and hydraulic pump, the pointer of described grating chi and described plunger are synchronized with the movement, and described pressure transducer, grating chi and motor are by described programmable controller controls;

Described pressure regulating valve is pressurization valve and pressure relief valve, and is arranged on the described pipeline and lays respectively at described tensimeter both sides;

Described plunger upper end is provided with the plunger pull bar, and described plunger is connected with described servomotor by this plunger pull bar, and the pointer of described grating chi is arranged on the described plunger pull bar.

2. bulk modulus measurement mechanism according to claim 1 is characterized in that: described hydraulic cylinder internal diameter is 60-350mm, and external diameter is 120-550mm.

3. bulk modulus measurement mechanism according to claim 1 is characterized in that: default one demarcates bloom in the interior cabin of described hydraulic cylinder, and the volume of described demarcation bloom equates with the volume of solid buoyancy material to be measured.

4. bulk modulus measurement mechanism according to claim 1, it is characterized in that: described measurement mechanism also comprises bracing or strutting arrangement, described bracing or strutting arrangement comprises hydraulic cylinder bracing or strutting arrangement and hydraulic pump bracing or strutting arrangement, wherein the hydraulic cylinder bracing or strutting arrangement comprises first support, be provided with the rotary lifting device that is used to promote described hydraulic cylinder in the upper end of first support, be provided with hydraulic cylinder pole in the both sides of described hydraulic cylinder, be provided with swivel bearing on first support, hydraulic cylinder is connected on the described swivel bearing by hydraulic cylinder pole and then is supported on described first support; The hydraulic pump bracing or strutting arrangement comprises second support that is used to support described hydraulic pump, and described motor is installed in the top of second support.

5. a method of testing of utilizing the described measurement mechanism of claim 1 to measure volume elastic modulus of solid buoyancy material is characterized in that comprising the steps:

(a) at first in hydraulic cylinder, put into one in the cabin and demarcate bloom;

(b) open pressurization valve and pressure relief valve, the water source is connected in the hydraulic pump lower end then, treat that internal system is full of water after, pressure relief valve can there are flowing out, and closes pressure relief valve this moment;

(c) configure precompression by programmable controller after, start servomotor, be moved by plunger pull bar pulling plunger, water in the hydraulic pump inner chamber is subjected to the extruding of plunger and produces pressure, and transfer the pressure to cabin in the hydraulic cylinder unchangeably by the connecting line size, this pressure affacts on the sample to be detected simultaneously, internal system pressure size is measured by pressure transducer, measurement data is sent to programmable controller, programmable controller compares this measurement data and the force value that configures, control servomotor if pressure does not reach and rotate, continue to exert pressure, reach setting value up to pressure;

(d) displacement of plunger is measured by the grating chi, and measurement data is write down on computers automatically by programmable controller, and computer calculates simultaneously because the volume change of the water that plunger displacement causes;

(e) can obtain the volume change of system under the pressure by above (c), (d) two steps, be a reference value with this data scaling;

(f) measure in the volume change under a series of pressure and demarcate respectively and be the reference value under the relevant pressure;

(g) behind the taking-up bloom, solid buoyancy material sample to be measured is put into hydraulic cylinder, add entry;

(h) water is forced into the static pressure of setting together with solid buoyancy material to be measured, plunger descends, and the static pressure of setting is decided according to the depth of water that buoyant material can be served in the device working range, then repeating step (d).

6. measuring method according to claim 5 is characterized in that: described plunger movement speed is 0.1-10mm/min.

7. measuring method according to claim 5 is characterized in that: the precompression that described programmable controller is set is 0.1～70MPa.

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