A device for testing lateral pressure of perlite

Abstract

The application discloses a perlite lateral pressure test device, which comprises a test box, a sliding plate and a loading mechanism. The test box comprises a base, a fixed back plate, a fixed top plate and two fixed side plates. The fixed back plate and the fixed side plates are fixedly installed on the base. The two fixed side plates are located on the left and right sides of the fixed back plate. The fixed top plate is fixedly installed on the fixed side plates and the fixed back plate to enclose a test chamber. The sliding plate is arranged vertically and is transversely movably arranged in the test chamber. The sliding plate is installed with a plurality of pressure sensors arranged vertically and spaced apart. An elastic felt is fixed on the side of the sliding plate facing the fixed back plate. Expanded perlite is filled between the elastic felt and the fixed back plate. The loading mechanism comprises a counterforce frame and a servo actuator. The counterforce frame is transversely arranged between the two fixed side plates. The counterforce frame is installed on the fixed side plates. The servo actuator is installed on the counterforce frame and is fixedly connected with the sliding plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of liquefied natural gas storage, in particular to a perlite lateral pressure test device. BACKGROUND

[0002] LNG refers to liquefied natural gas, and the demand is increasing. LNG storage is a very important link in the LNG industry, and the most commonly used and relatively mature storage technology in China at present is the full-capacity prestressed concrete storage tank.

[0003] LNG storage tanks have strict adiabatic measures, including tank bottom cooling, tank wall cooling and tank top cooling, among which expanded perlite as the key cold insulation material is filled in the annular space of the storage tank. The annular space is located between the prestressed reinforced concrete outer tank and the 9% Ni steel plate of the inner tank, and an elastic felt is laid on the outer side of the inner tank wall plate, and the other space of the inner wall thermal insulation layer is filled with expanded perlite. Expanded perlite and elastic felt are the main cold insulation materials between the inner tank wall and the outer tank wall of the LNG full-capacity storage tank, which has an important influence on the overall structure stress of the storage tank.

[0004] At present, the lateral pressure of the expanded perlite in the annular space of the storage tank is in the theoretical calculation stage, and there is a lack of means to verify the rationality of the theoretical calculation, which needs to be improved. SUMMARY

[0005] The present application provides a perlite lateral pressure test device, which solves the technical problem of verifying the rationality of the theoretical calculation of the lateral pressure of the expanded perlite in the annular space of the storage tank in the prior art.

[0006] The present application provides a perlite lateral pressure test device, which includes a test box, a sliding plate and a loading mechanism. The test box includes a base, a fixed back plate, a fixed top plate and two fixed side plates. The fixed back plate and the fixed side plates are fixedly installed on the base. The two fixed side plates are located on the left and right sides of the fixed back plate. The fixed top plate is fixedly installed on the fixed side plates and the fixed back plate to form a test chamber. The sliding plate is arranged vertically and movably arranged in the test chamber. The sliding plate is installed with a plurality of pressure sensors arranged vertically and spaced apart. An elastic felt is fixed on the side of the sliding plate facing the fixed back plate. Expanded perlite is filled between the elastic felt and the fixed back plate. The loading mechanism includes a counterforce frame and a servo actuator. The counterforce frame is transversely arranged between the two fixed side plates. The counterforce frame is installed on the side of the fixed side plate away from the fixed back plate. The servo actuator is installed on the counterforce frame and fixedly connected with the sliding plate to adjust the position of the sliding plate in the test chamber.

[0007] In some embodiments, the perlite lateral pressure test device further comprises a plurality of sets of gap adjusting assemblies, which are arranged in sequence in the height direction; the gap adjusting assembly comprises a gap adjusting rod, two threaded rods, two nuts and two L-shaped fixing pieces, the length of the gap adjusting rod is provided with a threaded hole in the length direction at both ends, the two threaded rods are threadedly connected to both ends of the gap adjusting rod through the threaded holes, the two nuts are threadedly installed on the threaded rods, and the nuts are located outside the gap adjusting rod, and the L-shaped fixing pieces are welded with the nuts.

[0008] In some embodiments, the fixed side plate is made of steel.

[0009] In some embodiments, a plurality of shock absorbers are installed at the bottom of the base.

[0010] In some embodiments, the loading mechanism comprises at least two counterforce frames, which are arranged in sequence in the height direction, and each counterforce frame is provided with at least two servo actuators.

[0011] In some embodiments, the servo actuators are provided with displacement sensors and force sensors to realize closed-loop control.

[0012] In some embodiments, a feeding port is arranged on the fixed top plate, and a discharging port is arranged on the fixed back plate, and the discharging port is provided with a butterfly valve for adjustment.

[0013] In some embodiments, a manhole door is arranged on the fixed back plate, which is closed and fixed by screws during the test.

[0014] In some embodiments, an elongated pad is arranged at the back spherical hinge of each servo actuator to adjust the filling space range of the expanded perlite.

[0015] In some embodiments, the load of the shock absorber is not less than 640kN, or each shock absorber is fixed to the foundation.

[0016] The application has the following advantages: the perlite lateral pressure test device is provided, which is used in the following manner: first, the elastic felt is fixed, then the expanded perlite is filled, and then the expanded perlite is vibrated and tamped until the data measured by the pressure sensor is stable within a certain range; the servo actuator is controlled to reciprocate at a certain frequency to adjust the position of the sliding plate in the test chamber, so that different lateral pressures are applied to the expanded perlite, and the perlite lateral pressure test is successfully carried out, including the simulation of tank contraction test and tank expansion test.

[0017] The test device of the application improves the safety and controllability of the test and the accuracy of stress data monitoring; compared with the actual field test, the test device has low cost, can be used for multiple and repeated tests, has short installation and construction period; the test results, i.e. the pressure values of each measuring point, generally show the trend that the upper pressure is relatively small and the lower pressure is relatively large; the test using the test device verifies the reliability of the theoretical calculation of the perlite lateral pressure, provides reference original data for the finite element numerical simulation, and provides theoretical and data support for the later LNG storage tank overall modeling and the study of the overall perlite lateral pressure. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application.

[0019] Figure 1 A rear view of the perlite lateral pressure test device provided by the application;

[0020] Figure 2 A front view of the perlite lateral pressure test device provided by the application;

[0021] Figure 3 A top view of the perlite lateral pressure test device provided by the application;

[0022] Figure 4 A bottom view of the perlite lateral pressure test device provided by the application;

[0023] Figure 5 A sectional view of the perlite lateral pressure test device provided by the application;

[0024] Figure 6 A specific structure diagram of the slot adjusting rod in the device provided by the application.

[0025] The drawings are labeled as follows: 1 - shock absorber, 2 - base, 3 - discharge port, 4 - butterfly valve, 5 - manhole door, 6 - pressure sensor, 7 - L-shaped fixing piece, 71 - nut, 8 - slot adjusting rod, 81 - threaded rod, 9 - fixed rear plate, 10 - fixed side plate, 11 - sliding plate, 12 - fixed top plate, 13 - inlet, 14 - elastic felt, 15 - expanded perlite, 16 - counterforce frame, 17 - lengthened pad, 18 - servo actuator. DETAILED DESCRIPTION

[0026] The application provides a perlite lateral pressure test device, which is described in combination with reference to Figures 1 to 4 , which sequentially shows the rear view, front view, top view and bottom view of the device, Figure 5 which showsFigure 1 and Figure 2 the cross-sectional view of the middle 1-1.

[0027] Please refer to Figure 1 , Figure 2 and Figure 5 , the device includes a test box, the test box is designed in a box structure, the base 2, the fixed back plate 9, the fixed top plate 12 and the two fixed side plates 10, the base 2 is arranged at the bottom side, the fixed back plate 9 is arranged at the back side, the fixed top plate 12 is arranged at the top side, and the two fixed side plates 10 are arranged at the left and right sides, and the front side is arranged open. In detail, the fixed back plate 9 and the fixed side plate 10 are fixedly installed on the base 2, the two fixed side plates 10 are located at the left and right sides of the fixed back plate 9, the fixed top plate 12 is fixedly installed on the fixed side plate 10 and the fixed back plate 9, so as to form a test chamber in the test box, and the front side of the test chamber is arranged open, or in other words, a movable sliding plate 11 is arranged at the front side of the test chamber.

[0028] Please refer to Figures 2 to 5 , the device includes a sliding plate 11, the sliding plate 11 is arranged vertically, the sliding plate 11 is arranged as a vertical plate, and it is movably arranged at the front side of the test chamber, and the moving direction is transverse. As Figure 2 shown, a plurality of pressure sensors 6 are installed on the sliding plate 11, and the plurality of pressure sensors 6 are arranged vertically and spaced apart in sequence, Figure 2 a layout scheme of a row of 8 pressure sensors 6 is shown. Please refer to Figure 5 , the elastic felt 14 is fixed at the side of the sliding plate 11 facing the fixed back plate 9, and the expanded perlite 15 is filled between the elastic felt 14 and the fixed back plate 9.

[0029] Please refer to Figures 2 to 5 , the device includes a loading mechanism, the loading mechanism includes a counterforce frame 16 and a servo actuator 18, the counterforce frame 16 is transversely arranged between the two fixed side plates 10, the counterforce frame 16 is installed on the side of the fixed side plate 10 away from the fixed back plate 9, and the servo actuator 18 is installed on the counterforce frame 16. The servo actuator 18 is fixedly connected with the sliding plate 11 to adjust the position of the sliding plate 11 in the test chamber.

[0030] In use, first fix the elastic felt 14, fix the elastic felt 14 on the sliding plate 11 in a suspended manner, and form an annular space between the elastic felt 14 and the fixed back plate 9, the top side of the annular space is the fixed top plate 12, the bottom side is the base 2, and the left and right sides are the two fixed side plates 10.

[0031] After the elastic felt 14 is fixed, the pressure values of the 8 measuring points are recorded by the pressure sensor 6. Then the expanded perlite 15 is filled in the annular space, and after the initial filling, the pressure values of the 8 measuring points and the weight of the filler are recorded. Then the expanded perlite 15 is vibrated and tamped, and after 5 minutes of standing, the pressure values of the 8 measuring points are recorded. Then the pressure values of the 8 measuring points are recorded every 5 minutes, at least three times, until the pressure difference between the two records is not more than 0.1 N, which is stable, and is represented as the data measured by the pressure sensor 6 is stable within a certain range.

[0032] After the pressure difference is stable, the simulated tank shrinkage test is started, the test stroke is specified according to the working condition, and the data is recorded after standing; then the simulated tank expansion test is started, the test stroke is specified according to the working condition, and the data is recorded after standing; the data is analyzed and the next cycle is started.

[0033] When the device is tested, the servo actuator 18 is controlled to reciprocate at a certain frequency to adjust the position of the sliding plate 11 in the test chamber, so as to apply different lateral pressures to the expanded perlite 15, and the perlite lateral pressure test is smoothly carried out, including the simulated tank shrinkage test and the simulated tank expansion test.

[0034] Through the device, the safety and controllability of the test are improved, and the accuracy of stress data monitoring is improved. Compared with the actual field test, the test device has the advantages of low cost, and the device can be tested multiple times, repeated, and has a short installation and construction period.

[0035] The test results of the device, i.e. the pressure values of each measuring point, generally show a trend that the upper pressure is relatively small and the lower pressure is relatively large. By using the test device for experiments, the reliability of the theoretical calculation of the perlite lateral pressure is verified, and reference data for finite element numerical simulation is provided, which provides theoretical and data support for later LNG tank overall modeling and research on overall perlite lateral pressure.

[0036] Considering that the two fixed side plates 10 may receive outward extrusion force during the test, in some embodiments, the gap adjusting rod 8 is used to maintain the stability of the spacing distance of the two fixed side plates 10. In detail, the perlite lateral pressure test device further includes a plurality of gap adjusting assemblies, and the gap adjusting assembly includes the gap adjusting rod 8, as shown in Figure 2 The plurality of gap adjusting assemblies are arranged in sequence in the height direction.

[0037] Please refer to Figure 2 , Figure 5 and Figure 6 , the gap adjusting assembly includes the gap adjusting rod 8, two threaded rods 81, two nuts 71 and two L-shaped fixing pieces 7, the gap adjusting rod 8 has length ends, and at each length end, a threaded rod 81, a nut 71 and an L-shaped fixing piece 7 are arranged respectively. For details, please refer to Figure 6The lengthwise ends of the gap-adjusting rod 8 are provided with threaded holes arranged along the length direction, a threaded rod 81 is threadedly connected with the gap-adjusting rod 8 through the threaded holes, and a nut 71 is threadedly installed on the threaded rod 81 and located outside the gap-adjusting rod 8. The L-shaped fixing member 7 is welded with the nut 71, and the nut 71 is rotated by rotating the L-shaped fixing member 7, so as to adjust the outward extension or inward retraction of the threaded rod 81 relative to the gap-adjusting rod 8, thereby adjusting the overall length of the gap-adjusting rod 8 and the threaded rod 81.

[0038] By arranging the gap-adjusting rod 8, the threaded rods 81 at the two ends of the gap-adjusting rod 8 abut against the inner side of the fixed side plate 10, the spacing of the fixed side plate 10 at this position is maintained unchanged, the smooth movement of the sliding plate 11 is ensured, the fixed side plate 10 is prevented from blocking the sliding plate 11, and the sealing between the fixed side plate 10 and the sliding plate 11 is maintained.

[0039] In the device, the fixed side plate 10 can be made of steel.

[0040] In some embodiments, referring to Figure 1 and Figure 4 , a plurality of shock absorbers 1 are installed at the bottom of the base 2. Each shock absorber 1 at the bottom of the device bears a load of no less than 640 kN, or each shock absorber 1 is fixed with the foundation.

[0041] In some embodiments, referring to Figure 4 and Figure 5 , a lengthened pad 17 is arranged at the rear spherical hinge of each servo actuator 18, for adjusting the annular space and adjusting the filling space range of the expanded perlite 15.

[0042] In some embodiments, the loading mechanism includes at least two counterforce frames 16, Figure 2 The scheme of two counterforce frames 16 is shown in Figure 2 The at least two counterforce frames 16 are arranged at intervals in height, and each counterforce frame 16 is installed with at least two servo actuators 18, Figure 2 The scheme of two servo actuators 18 installed in each counterforce frame 16 is shown in

[0043] In some embodiments, the servo actuator 18 is provided with a displacement sensor and a force sensor, the displacement sensor and the force sensor are installed on the servo actuator 18, and closed-loop control is realized. The servo actuator 18 is connected with the sliding plate 11 through bolts, and the actuator is controlled to reciprocate at a certain frequency, so as to realize the function of changing the annular space.

[0044] In some embodiments, referring to Figure 3 , the fixed top plate 12 is provided with a feeding port 13, referring to Figure 4 , the fixed rear plate 9 is provided with a discharging port 3, and the discharging port 3 is provided with a butterfly valve 4 for adjustment.

[0045] In some embodiments, please refer to Figure 1 A manhole door 5 is provided in the fixed back plate 9, near the bottom side of the fixed back plate 9. The manhole door 5 is closed during the test, and is fixed by screws around.

[0046] While the preferred embodiments of the application have been described, additional variations and modifications can be made to the preferred embodiments by those skilled in the art once they learn of the basic inventive concepts. Therefore, the appended claims are intended to encompass within their scope all such variations and modifications as are included within the scope of the invention.

[0047] Obviously, numerous modifications and variations of the present application are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A perlite lateral pressure testing device, characterized in that, include: The test chamber includes a base, a fixed back plate, a fixed top plate, and two fixed side plates. The fixed back plate and the fixed side plates are both fixedly installed on the base. The two fixed side plates are located on the left and right sides of the fixed back plate. The fixed top plate is fixedly installed on the fixed side plates and the fixed back plate to enclose the test chamber and form a test chamber. A sliding plate is arranged vertically and is laterally movable in the test chamber. The sliding plate is equipped with a plurality of pressure sensors arranged vertically at intervals. An elastic felt is fixed on the side of the sliding plate facing the fixed back plate, and expanded perlite is filled between the elastic felt and the fixed back plate. The loading mechanism includes a reaction frame and a servo actuator. The reaction frame is laterally spanned between the two fixed side plates and is installed on the side of the fixed side plates away from the fixed rear plate. The servo actuator is installed on the reaction frame and is fixedly connected to the sliding plate to adjust the position of the sliding plate in the test chamber. Multiple sets of gap adjustment components are arranged sequentially at intervals along the height direction. Each gap adjustment component includes an adjustment rod, two threaded rods, two nuts, and two L-shaped fasteners. Threaded holes are respectively opened at both ends of the adjustment rod along its length. The two threaded rods are threadedly connected to both ends of the adjustment rod through the threaded holes. The two nuts are respectively threaded onto the threaded rods and are located outside the adjustment rods. The L-shaped fasteners are welded to the nuts.

2. The perlite lateral pressure testing apparatus as described in claim 1, characterized in that, The fixed side plate is made of steel.

3. The perlite lateral pressure testing apparatus as described in claim 1, characterized in that, Multiple shock absorbers are installed at the bottom of the base.

4. The perlite lateral pressure testing apparatus as described in claim 1, characterized in that, The loading mechanism includes at least two reaction frames, which are arranged at a height interval, and each reaction frame is equipped with at least two servo actuators.

5. The perlite lateral pressure testing apparatus as described in claim 1, characterized in that, The servo actuator is equipped with a displacement sensor and a force sensor to achieve closed-loop control.

6. The perlite lateral pressure testing apparatus as described in claim 1, characterized in that, A feed inlet is provided on the fixed top plate, and a discharge outlet is provided on the fixed rear plate. The discharge outlet is equipped with a butterfly valve for adjustment.

7. The perlite lateral pressure testing apparatus as described in claim 1, characterized in that, A manhole door was opened on the fixed rear plate. During the test, the manhole door was closed and fixed with screws.

8. The perlite lateral pressure testing apparatus as described in claim 1, 4, or 5, characterized in that, An extension pad is provided on the rear ball joint of each of the servo actuators to adjust the filling space range of the expanded perlite.

9. The perlite lateral pressure testing apparatus as described in claim 3, characterized in that, The load of the shock absorber shall not be less than 640kN, or each shock absorber shall be fixed to the foundation.

Images