Ventilation device for large long-distance pipeline

Abstract

The utility model relates to the technical field of engineering equipment, in particular to a ventilation device for a large-scale long-distance pipeline, which comprises a physical partition plate arranged in the pipeline and used for isolating gas backflow in the pipeline; a through hole is formed in the upper portion of the physical partition plate, an air pipe penetrates through the through hole, and a fan is arranged in the air pipe. And a passage door for passing and closing is arranged at the lower part of the physical partition plate. The utility model has the advantages that the mounting and the dismounting are convenient; the ventilation and air exchange capacity is efficient; low-noise operation is realized; the method is environment-friendly.

Description

Technical Field

[0001] The utility model relates to the technical field of engineering equipment, and specifically relates to a ventilation device for large long-distance pipelines. Background Art

[0002] In the trenchless repair project of DN3500 pipelines, the construction of stainless steel linings involves multiple operations such as manual assembly of stainless steel segments, welding, and wall thickness grouting inside the pipelines. Such operations are carried out in a confined space, so there is a risk that workers may be poisoned or suffer from hypoxia. The currently adopted technology is to set up a air supply device at one end of the pipeline and an exhaust device at the other end to promote the air circulation and replacement inside the pipeline.

[0003] However, due to the space limitation at the construction site and the large diameter of the pipeline, it may be difficult to achieve an ideal air replacement effect only by means of air supply and exhaust. This may lead to poor air quality inside the pipeline and increase the safety risks for the operators. In order to improve this situation, there is an urgent need to design a more effective ventilation technology or device to ensure that the air quality inside the pipeline meets the safety standards. Summary of the Utility Model

[0004] The purpose of the utility model is to overcome the deficiencies of the prior art and provide a ventilation device for large long-distance pipelines, so as to provide a ventilation device in a confined space, which can improve the ventilation effect in the confined space and ensure the operation safety without affecting the welding quality and the construction operation surface.

[0005] In order to achieve the above purpose, a ventilation device for large long-distance pipelines is designed, including: a physical partition board arranged inside the pipeline, the physical partition board is used to block the gas backflow inside the pipeline; a through hole is opened in the upper part of the physical partition board, the through hole is used to pass through the air duct, and a fan is arranged inside the air duct; a passage door for passage and closing is arranged at the lower part of the physical partition board.

[0006] Preferably, the ventilation device for large long-distance pipelines provided by the utility model further includes other technical features, wherein the pipeline includes a concrete pipe wall and a stainless steel pipeline, drill holes in the concrete pipe wall, use expansion screws as anchor points as fixed points, assemble the stainless steel pipeline inside the concrete pipe wall, weld fixed points on the stainless steel pipe wall, install a fan and an air duct at the fixed points, and install the physical partition board to avoid the fan and the air duct.

[0007] Preferably, the ventilation device for large long-distance pipelines provided by the utility model further includes other technical features, wherein a notch is opened at the top of the physical partition board for avoiding the fan and the air duct.

[0008] Preferably, the large - scale long - distance pipeline ventilation device provided by the utility model further includes other technical features, wherein the physical partition board is made of a flame - retardant board or a steel plate.

[0009] Compared with the prior art, the advantages of the utility model are as follows:

[0010] 1. Convenient installation and disassembly: The ventilation device is easy to install and disassemble to adapt to medium - and short - term construction cycles. And it is a low - cost temporary facility. Compared with long - term ventilation systems such as mine roadway ventilation, it does not require large equipment and high investment.

[0011] 2. High - efficient ventilation and air change capacity: The device can provide a strong ventilation and air change effect to quickly remove harmful gases, dust, and moisture in the pipeline, ensure air circulation, and provide a safe breathing environment for operators.

[0012] 3. Low - noise operation: It creates a good working environment, and the ventilation device maintains a low - noise level during operation. It helps to reduce the hearing fatigue of operators and improve work concentration.

[0013] 4. Environment - friendly: Considering environmental protection factors, the impact of the ventilation device on the surrounding environment is minimized during use. Description of the Drawings

[0014] Figure 1 are the side - view sectional drawings of the structure of the utility model;

[0015] Figure 2 are the front - view drawings of the structure of the utility model;

[0016] In the figures: 1: Physical partition board, 2: Through - hole, 3: Air duct, 4: Fan, 5: Passage door, 6: Concrete pipeline, 7: Working well, 8: Plugging. Detailed Embodiments

[0017] To make the purpose, principle, and structure of the utility model clearer, the following further elaborates with reference to the drawings and specific embodiments.

[0018] The technical difficulty of the technical solution of the utility model is as follows: The flowing air formed by the ventilation device in the pipeline cannot have too high a wind speed, otherwise it will affect the welding quality; nor can it occupy too much space, otherwise it will affect construction operations; for the conventional ventilation method of welded pipelines, due to the large pipe diameter, when the power of the induced draft fan is small, the ventilation efficiency is poor, and there is a situation where the air flow rate is too slow in some areas.

[0019] <Embodiment 1>

[0020] See Figure 1 、 2, the present utility model innovatively proposes to provide a physical partition board 1 in the middle of the concrete pipe 6, so as to form two chambers in the concrete pipe 6, and through holes 2 are opened above the physical partition board 1. After the stainless steel pipe segments are pasted in the concrete pipe 6, an air duct 3 and a fan 4 are arranged at the top end inside the concrete pipe 6, and the air duct passes through the through holes 2 on the physical partition board 1 to span the two chambers. Working wells 7 vertically communicating with the ground are respectively arranged at both ends of the concrete pipe 6, and the working wells 7 ensure unobstructed air inlet and outlet at both ends of the pipe. A plug 8 is also arranged on one side of the working well 7 away from the concrete pipe 6 for placing objects in other non-working section pipes to prevent accidental leakage.

[0021] After the fan 4 operates, the air in one chamber on one side of the physical partition board 1 is continuously pumped out, and the air in the other chamber on the other side is continuously injected. The atmospheric pressures in the two chambers on both sides of the physical partition board 1 are respectively a positive pressure and a negative pressure. By creating a pressure difference between the two chambers, it is ensured that there is sufficient directional air flow in the pipe, avoiding the phenomenon of too small air flow velocity and disordered air flow direction in some areas of the pipe, improving the quality of ventilation and air change. At the same time, by controlling the air intake volume of the fan 4, the air flow velocity can be accurately controlled to avoid excessive air flow velocity affecting the welding effect.

[0022] Furthermore, a passage door 5 is opened on the physical partition board 1 for staff to pass through, and the passage door 5 can be closed during work to ensure the stability of the positive and negative pressures in the two chambers on both sides of the physical partition board 1.

[0023] Furthermore, this ventilation device is mainly implemented before and after the assembly of the stainless steel pipe segments. It is fixed on the concrete pipe 6 before assembly and fixed on the stainless steel pipe segments after assembly.

[0024] Drill holes in the wall of the concrete pipe 6, and use Ø12 expansion bolts as anchor points as fixed points. Carry out the patch assembly of the stainless steel pipe segments inside the concrete pipe 6. After the stainless steel pipe segments are spliced, weld the stainless steel pipe segments to the above fixed points, and hoist and install the fan 4 and the air duct 3 on the fixed points. After normal trial operation, install the physical partition board 1.

[0025] The partition material can be selected as a 3mm flame-retardant board or a steel plate for partitioning. The material of the passage door is the same as that of the partition.

[0026] Air volume calculation and fan selection:

[0027] (1) According to the air volume required for the breathing of operating personnel Q = k×m×q: Since there are multiple process flow operations in the same working section underground, the maximum number of workers m working at the same time is about 20 people; the amount of fresh air required per person per hour q is 3m 3 / min; the air volume reserve coefficient k is taken as 1.25.

[0028] Q需 = k×m×q = 1.25×20×3×60 = 4500 m 3 / h.

[0029] (2)Calculating the total volume V based on replacing all fresh air every half hour. Taking the longest section of 474 m (without middle ducts) as an example, V = 474×3.14×(3.5 / 2) 2 = 4558 m 3 / h.

[0030] Q 需 = V / T = 4558 / 0.5 = 9116 m 3 / h.

[0031] (3)Calculating according to the minimum air velocity of the standard section: The section S = 3.14×(3.5 / 2) 2 = 9.6 m 2 The minimum air velocity V = 0.12 m / s

[0032] Q 需 = V×S = 9.6×0.12×60×60 = 4147 m 3 / h.

[0033] Based on the calculation results, select a medium wind pressure and low speed fan. The air supply volume of 9116 m 3 / h is used as the reference for selecting the fan. Select the EG-6A axial flow ventilator. The air supply volume of the fan is 11500 - 16780 m 3 / h, the fan power is 1.8 kW, the wind pressure is 288 - 171 Pa, the efficiency is 63%, the rotation speed is 1450 r / min, and the duct diameter is 600 mm, which can meet the requirements.

[0034] <Example 2>

[0035] Based on Example 1, the through hole 2 on the physical partition plate 1 can be replaced with a notch. The scheme using the notch can still achieve the positive and negative pressures of the cavities on both sides of the physical partition plate 1, and this scheme has lower processing requirements for the physical partition plate 1 and is easier to implement.

[0036] The above is only the specific implementation manner of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art within the technical scope disclosed by this utility model, according to the technical solution and the concept of this utility model, makes equivalent replacements or changes, and should be covered within the protection scope of this utility model.

Claims

1. A ventilation device for large and long-distance pipelines, characterized in that include A physical partition plate disposed in the pipeline, the physical partition plate is used to isolate the gas backflow in the pipeline; A through hole is provided on the upper portion of the physical partition plate, and the through hole is used to pass an air duct, and a fan is provided in the air duct; A passage door for passing and closing is provided at the lower part of the physical partition plate.

2. A ventilation device for large and long distance pipelines as claimed in claim 1, characterized in that The pipeline includes a concrete pipe wall and a stainless steel pipe. Holes are drilled on the concrete pipe wall, expansion screws are used as anchor points as fixed points, the stainless steel pipe is assembled in the concrete pipe wall, the fixed points are welded on the stainless steel pipe wall, fans and air ducts are installed at the fixed points, and physical partition panels are installed to avoid the fans and air ducts.

3. A ventilation device for large and long distance pipelines as claimed in claim 2, characterized in that A notch is provided on the top of the physical partition plate to allow the fan and the air duct to pass through.

4. A ventilation device for large and long distance pipelines as claimed in claim 2, characterized in that The physical partition plate is made of flame-retardant plate or steel plate.

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