A kind of test device of mud cake decomposition of shield cutter with warm pressure chemical synergy

Abstract

The utility model relates to a shield cutter disc mud cake decomposition test device of warm pressure chemical synergic effect belongs to shield construction test equipment technical field. The shield cutter disc mud cake decomposition test device of warm pressure chemical synergic effect, include: organic glass test cylinder, the top of organic glass test cylinder is opened and has the mouth that places, adjustable temperature -rising mechanism, adjustable temperature -rising mechanism includes temperature controller, and the wiring end wire of temperature controller is connected with electric heater, through the integration of organic glass test cylinder, adjustable temperature -rising mechanism, air pressure adjusting mechanism and weighing bearing mechanism, can comprehensive simulation shield machine front high temperature, high pressure and the complex working condition of chemical solution, the decomposition behavior under the action of mud cake in multiple factors is truly reflected, has solved the difficult problem that present technique cannot reproduce temperature, pressure and chemical environment simultaneously and quantitative analysis decomposition process, has provided the key test platform for mud cake active prevention and treatment.

Description

Technical Field

[0001] This utility model relates to the technical field of shield tunneling test equipment, and in particular to a test device for the decomposition of mud cake on a shield cutterhead using a synergistic effect of temperature, pressure and chemistry. Background Technology

[0002] In shield tunneling in clay strata, mud cakes easily form on the cutterhead, leading to decreased tunneling efficiency, equipment wear, and the risk of surface subsidence. To move away from a passive cleaning approach, a mud cake decomposition experiment on the cutterhead was conducted. By simulating temperature, pressure, and chemical environments, the decomposition mechanism and rate of mud cakes were studied, and efficient prevention and control solutions were developed, providing crucial support for proactive prevention and disposal of mud cakes in engineering projects.

[0003] During shield tunnel construction, the formation of cutterhead cake can severely impact construction efficiency and safety. Currently, there is a lack of experimental equipment capable of comprehensively simulating temperature, pressure, and chemical environments and quantitatively analyzing cake decomposition behavior. Therefore, there is an urgent need for experimental equipment that can realistically reflect the cake decomposition process under complex working conditions. Utility Model Content

[0004] Therefore, it is necessary to address the current lack of a dedicated experimental device capable of simulating the temperature, pressure, and chemical environment during tunnel boring machine (TBM) construction to quantitatively study the decomposition process of cutterhead cake, and to provide a TBM cutterhead cake decomposition experimental device based on the synergistic effects of temperature, pressure, and chemical processes.

[0005] A test device for the decomposition of mud cake on a tunnel boring machine cutterhead using a thermo-barochemical synergistic effect includes: An acrylic glass test tube, wherein the top of the acrylic glass test tube has a placement opening; An adjustable heating mechanism is provided, which includes a temperature controller. The wiring terminals of the temperature controller are connected to an electric heater. The heating element of the electric heater extends into the interior of the acrylic test tube and is fixedly connected to the inner bottom wall of the acrylic test tube. A pressure regulating mechanism, comprising an air compressor, wherein the air port of the air compressor is fixedly connected to and communicates with a pressure controller, and the air port of the pressure controller is fixedly connected to an air pipe, one end of which extends into the interior of the plexiglass test cylinder. A weighing and bearing mechanism is embedded and installed inside the placement port.

[0006] In one embodiment, the weighing and bearing mechanism includes a sealing cover inserted into the top of the placement port, a digital display gravity sensor fixedly connected to the bottom of the sealing cover, and a hollow tray fixedly connected to the detection end of the digital display gravity sensor.

[0007] In one embodiment, the vertical cross-sectional shape of the sealing cap is T-shaped, and the sealing cap is disposed above the placement opening with a diameter larger than the inner side of the placement opening.

[0008] In one embodiment, a sealing ring that contacts the acrylic test tube is embedded in the lower surface of the sealing cap, and the placement opening is located inside the sealing ring.

[0009] In one embodiment, an adjustment handle is fixedly connected to the top of the sealing cap, and the corners of the adjustment handle are rounded.

[0010] In one embodiment, the number of electric heaters is two, and the two electric heaters are symmetrically distributed on both sides of the axis of the plexiglass test cylinder.

[0011] In one embodiment, the inner bottom wall of the plexiglass test cylinder is fixedly connected to and connected to a drain pipe, one end of which extends through the plexiglass test cylinder and is fixedly connected to and connected to an on / off valve.

[0012] In one embodiment, a filter screen cylinder connected to a drain pipe is fixedly connected to the inner side of the plexiglass test cylinder. The filter screen cylinder is cone-shaped, and the hollow tray and the electric heater are respectively disposed on the inner and outer sides of the filter screen cylinder.

[0013] Beneficial effects 1. The above-mentioned shield cutterhead mud cake decomposition test device with synergistic effects of temperature, pressure and chemistry, through the integration of an plexiglass test cylinder, an adjustable heating mechanism, an air pressure regulating mechanism and a weighing bearing mechanism, can comprehensively simulate the complex working conditions of high temperature, high pressure and chemical solution in front of the shield machine, and truly reflect the decomposition behavior of mud cake under the action of multiple factors. It solves the problem that existing technologies cannot simultaneously reproduce temperature, pressure and chemical environment and quantitatively analyze the decomposition process, and provides a key test platform for active mud cake prevention.

[0014] 2. This device uses a weighing and bearing mechanism to monitor changes in the weight of the mud cake in real time, accurately quantifying the decomposition rate and amount. At the same time, the filtration and sewage discharge design of the plexiglass test tube enables efficient separation and cleaning of residues and waste liquid, ensuring the continuity and repeatability of the experimental process. It solves the problems of insufficient measurement accuracy and cumbersome subsequent processing in traditional experiments, and significantly improves the efficiency and reliability of mud cake decomposition research. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a cross-sectional view of the overall structure of this utility model; Figure 3 This is a schematic diagram of the adjustable heating mechanism in this utility model; Figure 4 This is a schematic diagram of the air pressure regulating mechanism in this utility model; Figure 5 This is an exploded view of the weighing and bearing mechanism in this utility model.

[0017] Figure label: 100. Acrylic glass test cylinder; 110. Placement port; 120. Drain pipe; 130. On / off valve; 140. Filter screen cylinder; 200. Adjustable heating mechanism; 210. Temperature controller; 220. Electric heater; 300. Air pressure regulating mechanism; 310. Air compressor; 320. Air pressure controller; 330. Air pipe; 400. Weighing and bearing mechanism; 410. Sealing cover; 420. Digital display gravity sensor; 430. Hollowed-out tray; 440. Sealing ring; 450. Adjustment handle. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0019] The following is combined with Figure 1 - Figure 5 This invention describes a test device for the decomposition of mud cake on a tunnel boring machine cutterhead using a thermo-barochemical synergistic effect.

[0020] In one embodiment, a test device for the decomposition of mud cake on a tunnel cutterhead using a thermo-barochemical synergistic effect includes an plexiglass test cylinder 100, an adjustable heating mechanism 200, a pressure regulating mechanism 300, and a weighing and bearing mechanism 400.

[0021] like Figure 1 and Figure 2As shown, the top of the acrylic test cylinder 100 has a placement opening 110. The inner bottom wall of the acrylic test cylinder 100 is fixedly connected to and connected to a drain pipe 120. One end of the drain pipe 120 extends out of the acrylic test cylinder 100, and the other end of the drain pipe 120 is fixedly connected to and connected to an on / off valve 130. A filter cylinder 140 connected to the drain pipe 120 is fixedly connected to the inner side of the acrylic test cylinder 100. The filter cylinder 140 is conical in shape. A hollow tray 430 and an electric heater 220 are respectively set on the inner and outer sides of the filter cylinder 140. This conical structure can effectively block impurities from contacting the electric heater 220, prevent them from adhering and forming scale on the heating surface, and guide the decomposed residue to actively collect and smoothly enter the drain pipe 120.

[0022] like Figure 2 and Figure 3 As shown, the adjustable heating mechanism 200 includes a temperature controller 210. The wiring terminals of the temperature controller 210 are connected to an electric heater 220. The heating part of the electric heater 220 extends into the interior of the acrylic test cylinder 100 and is fixedly connected to the inner bottom wall of the acrylic test cylinder 100. There are two electric heaters 220, which are symmetrically distributed on both sides of the axis of the acrylic test cylinder 100. This symmetrical distribution structure is conducive to forming a uniform and stable heating area at the bottom of the test cylinder, ensuring the uniformity of the test temperature field.

[0023] like Figure 2 and Figure 4 As shown, the air pressure regulating mechanism 300 includes an air compressor 310, the air port of the air compressor 310 is fixedly connected to and communicates with an air pressure controller 320, the air port of the air pressure controller 320 is fixedly connected to an air pipe 330, and one end of the air pipe 330 extends into the interior of the plexiglass test cylinder 100. like Figure 2 and Figure 5 As shown, the weighing bearing mechanism 400 is embedded and installed inside the placement port 110; the weighing bearing mechanism 400 includes a sealing cover 410 inserted into the top of the placement port 110, a digital display gravity sensor 420 fixedly connected to the bottom of the sealing cover 410, and a hollow tray 430 fixedly connected to the detection end of the digital display gravity sensor 420; the vertical cross-sectional shape of the sealing cover 410 is T-shaped, and the diameter of the sealing cover 410 located above the placement port 110 is larger than the inner side of the placement port 110; a sealing ring 440 that contacts the plexiglass test cylinder 100 is embedded and installed on the lower surface of the sealing cover 410, and the placement port 110 is located inside the sealing ring 440; an adjusting handle 450 is fixedly connected to the top of the sealing cover 410, and the corners of the adjusting handle 450 are rounded.

[0024] Working principle: First, close the on / off valve 130 on the drain pipe 120 and inject a chemical solution into the plexiglass test cylinder 100; place the mud cake sample on the hollow tray 430 of the weighing bearing mechanism 400 and insert it through the placement port 110, so that the sealing cap 410 is pressed and sealed by the sealing ring 440. This structure effectively ensures the convenience of operation and the reliability of sealing under high pressure; then, start the electric heater 220 to heat the solution through the temperature controller 210 of the adjustable heating mechanism 200, and at the same time, the air compressor 310 and the air pressure controller 320 of the air pressure regulating mechanism 300 supply air into the cylinder through the air pipe 330. A set air pressure is applied to accurately simulate the actual synergistic environment of high temperature and high pressure in front of the tunnel boring machine. During the test, the digital display gravity sensor 420 integrated in the weighing and bearing mechanism 400 monitors the change in mud cake weight in real time, realizing accurate quantitative measurement of decomposition rate and decomposition amount. After the test, the pressure is released and the temperature is reduced. The opening and closing valve 130 is opened, and the residual liquid is filtered through the filter screen 140 and discharged through the sewage pipe 120. This design facilitates the efficient separation and cleaning of residue and waste liquid after the test, ensures the continuity and repeatability of the test process, and provides a stable and reliable test platform for systematic study of mud cake decomposition law.

[0025] It should be noted that the physical model of temperature controller 210 is PT100 temperature controller. As the sensing core of the temperature control system, it utilizes the characteristic that the resistance of platinum metal increases linearly with temperature to accurately convert temperature variables into resistance signals. These signals are sent to temperature controller 210, compared with the set value, and the on / off state of heater 220 is adjusted in real time to maintain the precise and stable temperature of the solution in the test cylinder.

[0026] The actual model of the electric heater 220 is a tubular electric heater with the model number SRY2. This element consists of a nickel-chromium alloy heating wire, a high-purity magnesium oxide powder insulation layer, and a stainless steel sheath. Its working principle is to generate Joule heat by using an electric current to heat the heating wire. The heat is efficiently conducted to the surface of the sheath through the dense magnesium oxide filler, so as to achieve uniform heating of the chemical solution inside the cylinder. In the experiment, the temperature controller 210 sets the target temperature and starts the heater to provide a stable thermal environment for the decomposition of the mud cake.

[0027] The physical model of the air pressure controller 320 is a diffused silicon air pressure controller, model WPCK03. Its core is a silicon piezoresistive chip and a stainless steel 316L diaphragm. When compressed air pressure acts on the diaphragm, it causes a change in the resistance of the internal Wheatstone bridge and outputs a standard electrical signal. This signal is connected to the air pressure controller 320 to monitor and provide feedback on the air pressure inside the cylinder in real time. The controller adjusts the air intake accordingly to accurately simulate the specific pressure conditions in front of the tunnel boring machine.

[0028] The digital gravity sensor 420 integrates a strain gauge weighing unit and a digital display module. When the weight of the mud cake is applied to the hollow tray 430, the elastic body deforms, causing the bridge to become unbalanced. The resulting weak voltage signal is processed by the internal amplifier and processor and directly converted into a weight value and displayed. During the test, it continuously monitors the change in the mass of the mud cake, providing accurate data for calculating the decomposition rate.

[0029] The actual model of air compressor 310 is Lexy Silent Oil-Free Air Compressor. This equipment uses a motor to drive a piston or screw to compress the intake air and store it in an air tank. Its oil-free lubrication design ensures the cleanliness of the output gas. In the process, it acts as an air pressure source, providing stable and clean compressed air to the sealed test cylinder according to the instructions of the air pressure controller 320 to create the required pressure environment. Its low noise characteristics ensure the quietness of the laboratory.

[0030] The above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A test device for the decomposition of mud cake on a tunnel boring machine cutterhead using a synergistic effect of thermo-barochemical reaction, characterized in that, include: An acrylic glass test tube (100) has a placement opening (110) at its top. An adjustable heating mechanism (200) includes a temperature controller (210), the wiring terminals of which are connected to an electric heater (220), the heating part of which penetrates into the interior of the acrylic test tube (100) and is fixedly connected to the inner bottom wall of the acrylic test tube (100). A pressure regulating mechanism (300) includes an air compressor (310), the air port of the air compressor (310) is fixedly connected to and communicates with a pressure controller (320), the air port of the pressure controller (320) is fixedly connected to an air pipe (330), one end of the air pipe (330) extends into the interior of the plexiglass test cylinder (100); A weighing load-bearing mechanism (400) is embedded in the inside of the placement port (110).

2. The shield cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 1, characterized in that, The weighing and bearing mechanism (400) includes a sealing cover (410) inserted into the top of the placement port (110), a digital display gravity sensor (420) is fixedly connected to the bottom of the sealing cover (410), and a hollow tray (430) is fixedly connected to the detection end of the digital display gravity sensor (420).

3. The shield cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 2, characterized in that, The vertical cross-sectional shape of the sealing cap (410) is T-shaped, and the sealing cap (410) is located above the placement opening (110) with a diameter larger than the inner side of the placement opening (110).

4. The shield cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 2, characterized in that, The lower surface of the sealing cap (410) is fitted with a sealing ring (440) that contacts the plexiglass test cylinder (100), and the placement port (110) is located inside the sealing ring (440).

5. The shield cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 2, characterized in that, An adjustment handle (450) is fixedly connected to the top of the sealing cover (410), and the corners of the adjustment handle (450) are rounded.

6. The shield cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 2, characterized in that, The number of electric heaters (220) is two, and the two electric heaters (220) are symmetrically distributed on both sides of the axis of the plexiglass test cylinder (100).

7. The shield tunnel cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 6, characterized in that, The inner bottom wall of the plexiglass test tube (100) is fixedly connected to and connected to a drain pipe (120). One end of the drain pipe (120) extends through the plexiglass test tube (100), and the other end of the drain pipe (120) is fixedly connected to and connected to an on / off valve (130).

8. The shield cutterhead mud cake decomposition test device with synergistic thermo-barochemical effect according to claim 7, characterized in that, The inner side of the plexiglass test tube (100) is fixedly connected to a filter screen tube (140) that communicates with the drain pipe (120). The filter screen tube (140) is cone-shaped. The hollow tray (430) and the electric heater (220) are respectively set on the inner and outer sides of the filter screen tube (140).

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