Cement pipe hand digging type pipe jacking construction closed space air supply and exhaust system

Abstract

The invention discloses a cement pipe hand digging type pipe jacking construction closed space air supply and exhaust system which comprises an original soil layer, a working pipe, a curved surface air pipe, an air supply box and an oxygen content detector, the working pipe is arranged in the original soil layer, the curved surface air pipe is installed on the top in the working pipe, a plurality of air supply outlets are formed in the curved surface air pipe, and the oxygen content detector is arranged in the air supply box. The multiple air supply outlets are located in the position close to one side of a working area in the working pipe, the air supply box is installed on the other side of the curved-surface air pipe, the air supply end of the air supply box is communicated with the interior of the curved-surface air pipe, and the oxygen content detector is installed in the working area in the working pipe. The air supply box is provided with a signal receiver used for receiving signals sent by the oxygen content detector. The device is high in safety and low in manufacturing cost, meanwhile, by controlling the noise level, the comfort degree of the working environment is remarkably improved, and good economical efficiency and practicability are achieved.

Description

Technical Field

[0001] The invention relates to the technical field of exhaust ventilation, and in particular to an air supply and exhaust system for a confined space in a cement pipe hand-dug jacking construction. Background Art

[0002] At present, the ventilation system for the confined space of cement pipe hand-dug jacking construction mostly uses the pipe mouth blowing method to supply air to the inside of the pipe. When the soil-dumping rail car is transporting soil outside, the two-speed blower fan needs to be moved away from the pipe mouth, and the air supply in the closed pipe is stopped. When the soil-dumping rail car enters the pipe again, the two-speed blower fan needs to be placed at the pipe mouth again before it can supply air to the inside. This is time-consuming and labor-intensive, and it cannot guarantee uninterrupted air supply in the confined space. Due to the limited range of the two-speed blower fan, when the length of the cement pipe exceeds the range of the two-speed blower fan, the innermost working area of ​​the pipe cannot be effectively supplied with air, and the oxygen content in the working environment cannot be guaranteed, which greatly reduces the safety of the working environment. Summary of the invention

[0003] In order to solve the above problem, the present invention provides a confined space air supply and exhaust system for cement pipe hand-dug jacking construction to solve the problem.

[0004] In order to achieve the above objectives, this application provides the following technical solutions:

[0005] A confined space air supply and exhaust system for cement pipe hand-dug jacking construction, comprising an original soil layer, a working pipe, a curved air duct, an air supply box, and an oxygen content detector. The working pipe is placed in the original soil layer, the curved air duct is installed on the top of the working pipe, a plurality of air supply ports are opened on the curved air duct, and the plurality of air supply ports are located on one side close to a working area in the working pipe. The air supply box is installed on the other side of the curved air duct, and the air supply end of the air supply box is connected to the inside of the curved air duct. The oxygen content detector is installed in the working area in the working pipe; the air supply box is provided with a signal receiver for receiving signals sent by the oxygen content detector.

[0006] It is further configured as follows: a plurality of air supply ports are opened on the lower surface of the curved air duct.

[0007] It is further configured as follows: a tie strap is provided inside the curved air duct.

[0008] It is further configured as follows: a plurality of the curved surface air ducts are provided, and the plurality of the curved surface air ducts are connected by cables.

[0009] It is further configured as follows: a plurality of first embedded steel plates are horizontally arranged on the inner top of the working tube, and a strong magnetic hook is provided on the lower surface of the first embedded steel plate for magnetic attraction; air duct hanging points are evenly arranged on the outer top of the curved air duct, and the strong magnetic hook passes through the air duct hanging points and is adsorbed on the first embedded steel plate.

[0010] It is further configured as follows: a plurality of second embedded steel plates are horizontally arranged on the inner side of the working tube, a magnetic block is arranged on the oxygen content detector, and the oxygen content detector is magnetically attracted to the second embedded steel plates through the magnetic block.

[0011] It is further configured as follows: an air supply module and a refrigeration module are arranged inside the air supply box.

[0012] It is further configured as follows: the calculation formula for the height of the curved air duct is:

[0013] In the formula, h represents the height of the curved air duct; R represents the inner radius of the working pipe; N represents the number of workers inside the working pipe.

[0014] It is further configured as follows: the calculation formula for the cross-sectional length of the curved air duct is:

[0015] l=0.78πR; where l represents the cross-sectional length of the curved air duct; and R represents the inner radius of the working tube.

[0016] The calculation formula for the number of air outlets is:

[0017] Where n represents the number of air outlets; N represents the number of workers inside the working tube; and d represents the aperture of the air outlet.

[0018] Compared with the prior art, the beneficial technical effects of the present invention are:

[0019] 1. The present invention abandons the traditional duct material and shape, and uses flame-retardant fiber fabric curved duct. The system cost is low, the installation space required is small, and the effective working space inside the working pipe is not affected, so that the soil dumping rail car can operate normally;

[0020] 2. Compared with the traditional nozzle air blast, the present invention is not affected by the length of the cement pipe. The curved air duct can be extended by zipper connection and splicing, and fresh air is continuously and directly delivered to the working area. The air temperature and humidity are controllable, which greatly improves the safety and comfort of the working environment. The system has two working modes: normal air supply and emergency air supply. The two working modes can be switched automatically according to the oxygen concentration in the working area to ensure that the oxygen concentration in the working area always meets the requirements of the operators, which greatly improves the safety of the working environment.

[0021] In summary, the air supply and exhaust system provided by the present invention has high safety and low cost, and at the same time significantly improves the comfort of the working environment by controlling the noise level, and has good economy and practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 It is a front view of the present invention;

[0025] Figure 3 for Figure 2 The enlarged schematic diagram of the middle A part;

[0026] Figure 4 Schematic diagram of the appearance of the curved air duct of the present invention;

[0027] Figure 5 It is a schematic diagram of the internal structure of the curved air duct of the present invention;

[0028] Figure 6 It is a schematic diagram of the connection of multiple curved air ducts in the present invention.

[0029] Figure numerals: 1. original soil layer; 2. working pipe; 3. curved air duct; 4. air supply box; 5. oxygen content detector; 6. first embedded steel plate; 7. strong magnetic hook; 8. tie belt; 9. air duct hanging point; 10. second embedded steel plate; 11. magnetic block. DETAILED DESCRIPTION

[0030] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Example

[0034] Reference Figure 1-Figure 6 , which is a confined space air supply and exhaust system for cement pipe hand-dug jacking construction disclosed by the present invention, comprising an original soil layer 1, a working pipe 2, a curved air duct 3, an air supply box 4, and an oxygen content detector 5, wherein the working pipe 2 is a cement pipe and is buried in the original soil layer 1, and a plurality of first embedded steel plates 6 are horizontally arranged on the inner top of the working pipe 2, and a strong magnetic hook 7 is arranged on the lower surface of the first embedded steel plate 6;

[0035] In this embodiment, a plurality of curved air ducts 3 are provided, and the plurality of curved air ducts 3 are connected by cables. Furthermore, the plurality of curved air ducts 3 are all made of flame-retardant fiber fabrics, and a tie band 8 is provided inside the plurality of curved air ducts 3 to ensure that the air duct is in a curved shape when the internal pressure is positive; the curvature of the curved air duct 3 is the same as that of the cement pipe, so as to minimize the space inside the cement pipe and ensure that the air duct does not affect the hand excavation operation;

[0036] Furthermore, air duct hanging points 9 are evenly arranged on the outer top of the curved air duct 3, and the strong magnetic hook 7 passes through the air duct hanging point 9 and is adsorbed on the first embedded steel plate 6, so that the curved air duct 3 is hung on the inner top side of the working pipe 2;

[0037] The calculation formula for the height of the curved air duct 3 is:

[0038]

[0039] In the formula, h represents the height of the curved air duct; R represents the inner radius of the working pipe; N represents the number of workers inside the working pipe.

[0040] The calculation formula for the cross-sectional length of the curved air duct 3 is:

[0041] l=0.78πR (Formula 2);

[0042] In the formula, l represents the cross-sectional length of the curved duct; R represents the inner radius of the working tube.

[0043] A plurality of air supply ports are provided on the inner bottom wall of the curved air duct 3;

[0044] In this embodiment, the air supply port is opened on a side close to the working area in the working tube.

[0045] The calculation formula for the number of air outlets is:

[0046]

[0047] Where n represents the number of air outlets; N represents the number of workers inside the working tube; d represents the aperture of the air outlet, which is 2 cm.

[0048] The air supply box 4 is arranged on the side of the curved air duct 3 farthest from the air supply port. Specifically, the air supply end of the air supply box 4 is connected to the interior of the curved air duct 3. The interior of the air supply box 4 is provided with an air supply module and a refrigeration module to meet the temperature and humidity requirements of the staff.

[0049] A plurality of second embedded steel plates 10 are horizontally arranged on the inner side of the working tube 2, and a magnetic block 11 is arranged on the oxygen content detector 5. The oxygen content detector 5 is magnetically attracted to the second embedded steel plates 10 through the magnetic block 11;

[0050] The air supply box 4 is provided with a signal receiver for receiving the signal sent by the oxygen content detector 5. To ensure that the oxygen content of the operation in the confined space of the cement pipe hand-dug jacking construction meets the needs of personnel.

[0051] In this embodiment, the refrigeration module can be in the form of "semiconductor refrigeration plate + heat exchange fin plate", or use a window air conditioner, both of which achieve refrigeration by consuming electrical energy. The refrigeration working principle of the refrigeration module is a conventional technology in the relevant technical field and will not be described in detail here.

[0052] The air supply module adopts a two-speed fan. The low-speed operation state of the two-speed fan is used for normal air supply, and the high-speed operation state of the two-speed fan is used for emergency air supply. Specifically, when the oxygen concentration in the working area is lower than the lower limit, the oxygen content detector 5 sends a signal to the signal receiver of the air supply box 4, and the fan of the air supply box 4 is immediately switched from the low-speed normal air supply operation state to the high-speed emergency air supply state, increasing the air supply volume in the working area. When the oxygen concentration in the working area reaches the upper limit, the oxygen content detector 5 sends a signal to the signal receiver of the air supply box 4, and the operation state of the fan of the air supply box 4 is switched back to the low-speed normal air supply state, thereby realizing the automatic maintenance function of the oxygen content in the working area.

[0053] The present invention directly supplies air to the working area, so that the wind pressure in the working area in the working pipe 2 is increased, forming a wind pressure difference from the working area to the inlet end of the working pipe 2, and forming an air flow direction from the working area of ​​the working pipe 2 to the inlet of the cement pipe in the pipeline, so that the air flow inside the cement pipe is unobstructed.

[0054] Furthermore, the cross section of the connection between the air box 4 of the air supply module of the curved air duct 3 and the curved air duct 3 is taken as cross section 1, and the pressure at this cross section is P1 (that is, the side pressure of the curved air duct), and the cross section at the air outlet of the curved air duct is taken as cross section 2, and the pressure at this cross section is P2. The pressure drop between cross section 1 and cross section 2 is P 1-2 According to Bernoulli's equation:

[0055] P1=P 1_2 +0.25ρ(Formula 4);

[0056] Where ρ is the air density; from Formula 4, it can be seen that when selecting the fabric material of the curved air duct 3, it is only necessary to ensure that the material pressure is greater than the side pressure P1 of the curved air duct.

[0057] Furthermore, the cross section of the working tube at the air supply port is taken as cross section 3, the pressure at this cross section is P3, the cross section at the outlet of the working tube 2 is taken as cross section 4, the pressure at this cross section is P4, and the pressure drop between cross sections 3 and 4 is P 3-4 According to Bernoulli's equation:

[0058] P3=P 3_4 (Formula 5);

[0059] According to the "Design Code for Heating, Ventilation and Air Conditioning of Industrial Buildings GB50019-2015", the pressure difference between different air conditioning areas should be 5Pa~10Pa, so P3=P 3-4 =5Pa~10Pa, the ventilation requirements can be met; when P3 is greater than the set value, a wind shield curtain is set inside the curved air duct. When P3 is less than the set value, P3 can be increased by adding a fan to meet the ventilation requirements.

[0060] The present invention also takes noise control into consideration to improve the comfort of the working environment. The calculation formula of the sound power level is:

[0061]

[0062] The working principle and beneficial effects of the present invention are:

[0063] The present invention abandons the traditional air duct material and shape, uses the flame-retardant fiber fabric curved air duct 3, the system cost is low, the installation space required is small, and the effective working space inside the working pipe 2 is ensured not to be affected, and the soil dumping track vehicle can operate normally;

[0064] Compared with traditional pipe-mouth air blowing, the present invention is not affected by the length of the cement pipe. The curved air duct 3 can be extended by zipper connection and splicing, and fresh air is continuously and directly delivered to the working area. The air temperature and humidity are controllable, which greatly improves the safety and comfort of the working environment. The system is provided with two working modes: normal air supply and emergency air supply. The two working modes can be switched automatically according to the oxygen concentration in the working area, ensuring that the oxygen concentration in the working area always meets the requirements of the operators, which greatly improves the safety of the working environment.

[0065] In summary, the present invention provides a confined space air supply and exhaust system for cement pipe hand-dug jacking construction, which has high safety and low cost, and at the same time significantly improves the comfort of the working environment by controlling the noise level, and has good economy and practicality.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A confined space ventilation system for cement pipe hand-dug jacking construction, characterized in that: The invention comprises an original soil layer (1), a working pipe (2), a curved air duct (3), an air supply box (4), and an oxygen content detector (5), wherein the working pipe (2) is placed in the original soil layer (1), the curved air duct (3) is installed at the top of the working pipe (2), a plurality of air supply ports are provided on the curved air duct (3), and the plurality of air supply ports are located at one side of a working area in the working pipe (2), the air supply box (4) is installed on the other side of the curved air duct (3), and the air supply end of the air supply box (4) is connected to the inside of the curved air duct (3), and the oxygen content detector (5) is installed in the working area in the working pipe (2); the air supply box (4) is provided with a signal receiver for receiving the signal sent by the oxygen content detector (5).

2. A confined space ventilation system for cement pipe hand-dug jacking construction according to claim 1, characterized in that: The plurality of air supply ports are opened on the lower surface of the curved air duct (3).

3. A confined space ventilation system for cement pipe hand-dug jacking construction according to claim 1, characterized in that: A tie belt (8) is provided inside the curved air duct (3).

4. A confined space ventilation system for cement pipe hand-dug jacking construction according to claim 1, characterized in that: A plurality of the curved surface air ducts (3) are provided, and the plurality of the curved surface air ducts (3) are connected with each other by using cables.

5. The air supply and exhaust system for a confined space in cement pipe hand-dug jacking construction according to claim 1 is characterized in that: A plurality of first embedded steel plates (6) are horizontally arranged at the inner top of the working tube (2), and a strong magnetic hook (7) is arranged on the lower surface of the first embedded steel plate (6); air duct hanging points (9) are evenly arranged at the outer top of the curved air duct (3), and the strong magnetic hook (7) passes through the air duct hanging points (9) and is adsorbed on the first embedded steel plate (6).

6. A confined space ventilation system for cement pipe hand-dug jacking construction according to claim 1, characterized in that: A plurality of second embedded steel plates (10) are horizontally arranged on the inner side of the working tube (2), a magnetic block (11) is arranged on the oxygen content detector (5), and the oxygen content detector (5) is magnetically attracted to the second embedded steel plates (10) via the magnetic block (11).

7. The air supply and exhaust system for a confined space in cement pipe hand-dug jacking construction according to claim 1 is characterized in that: An air supply module and a refrigeration module are arranged inside the air supply box (4).

8. The air supply and exhaust system for a confined space in cement pipe hand-dug jacking construction according to claim 1 is characterized in that: The calculation formula for the height of the curved air duct (3) is: In the formula, h represents the height of the curved air duct; R represents the inner radius of the working pipe; N represents the number of workers inside the working pipe.

9. The air supply and exhaust system for a confined space in cement pipe hand-dug jacking construction according to claim 1, characterized in that: The calculation formula for the cross-sectional length of the curved air duct (3) is: l=0.78πR; wherein l represents the cross-sectional length of the curved air duct; and R represents the inner radius of the working tube.

10. A confined space ventilation system for cement pipe hand-dug jacking construction according to claim 1, characterized in that: The calculation formula for the number of air outlets is: Where n represents the number of air outlets; N represents the number of workers inside the working tube; and d represents the aperture of the air outlet.

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