Common sense of culvert dredging safety

Yonghua Sewage Company1388,2198,474 introduces the knowledge about culverts based on many years of on-site construction experience.

A culvert is a passage where a road or railway intersects a ditch, so that water can flow under the road. They have the same function as bridges, but usually have smaller apertures and shapes, such as pipes, boxes and arches. In addition, the culvert is also a cave-type water conservancy facility with a gate to adjust the water volume.

According to the structural form, it can be divided into circular tube culvert, arch culvert, slab culvert and box culvert. After a period of use, silt impurities precipitate, which affects flood discharge and drainage. Dredging and dredging should be carried out regularly. Precautions and construction methods of culvert dredging and cleaning The vertical height of drainage ditch entering culvert and the length of culvert determine the construction difficulty and harmful gas concentration.

Workers should wear gas masks when entering culvert operations and pay attention to ventilation and exhaust. According to years of construction experience, workers observe whether there are explosive gas bottles, highly corrosive impurities and chemical wastes while cleaning impurities.

The culvert construction method should be determined according to the type, length and depth of culvert impurities and the actual situation on site. For example, the pure mud in the culvert can be extracted by high-pressure washing and dirt suction vehicle.

If there are many impurities, slag and branches in the culvert, it can be cleaned manually and transported by electric hoist. In short, it is safe, convenient and fast according to the actual situation.

2. How to dredge drainage culverts and specific practices.

Use a high-pressure cleaning vehicle, or manually pull, push and pull to clean the sludge in the pipeline to the outside of the pipeline, and then transport it to the designated place. If the pipeline needs to be cleaned until there is no sludge, the inner wall of the pipeline needs to be cleaned repeatedly. You can use CCTV visual images to take pictures of the pipeline to see the internal situation of the pipeline, so as to understand the dredging situation of the pipeline. It is used to dredge rainwater pipes, sewage pipes, open channels and culverts with different depths and diameters.

First, the dredging process

1. Precipitation and drainage

Drain the sewage in the inspection well into the mud at the bottom of the well with a mud pump. The pipeline to be dredged shall be segmented, and the segmentation method shall be distributed according to the pipe diameter and length, with a section between two inspection wells with the same pipe diameter.

2. Dilute sludge

High-pressure waterwheel injects water into the well chamber from two segmented inspection wells, and the sludge in the inspection wells and sewage pipes is stirred by dredger to dilute the sludge; Artificial should cooperate with machinery to continuously stir the sludge until it is diluted into water.

Suck dust

The sludge in the two inspection wells is completely sucked by the sewage suction truck, and a small amount of sludge left in the two inspection wells impacts the sludge at the bottom of the well chamber with a high-pressure water gun, and is diluted again to complete the suction.

Intercept pollution

Setting the plug will block the well chamber inlet pipeline of the first working section from top to bottom, and then block the outlet of the downstream inspection well and other pipeline openings, leaving only the inlet and outlet of this section of pipeline.

5. Clean the car and dredge it

Use the high-pressure cleaning vehicle to dredge the pipeline, extend the hose of the high-pressure cleaning vehicle into the lower part of the upstream inspection well, aim the water gun at the pipeline to spray water, and the inspection well downstream of the sewage pipeline will continue to suck indoor sludge.

ventilate

Before the construction workers enter the inspection well, they must put the oxygen in the atmosphere into the inspection well or ventilate it with a blower to measure the oxygen content in the well. Construction personnel must wear safety belts, gas masks and oxygen cylinders when entering the well.

7. Dig mud

After arranging the safety measures of construction personnel before underground construction, manually clean up the remaining bricks, stones, part of sludge and other residues in the inspection well until the cleaning is completed.

Then, according to the above instructions, the downstream sewage inspection wells are dredged one by one, and the inspection wells cleaned first in the upstream are blocked during dredging, so as to prevent the upstream sludge from flowing into the pipeline or into the upstream inspection wells and pipelines when the pipeline is full of water in the downstream construction.

pay attention to

Rainwater pipes and sewage pipes artificially enter the pipeline, which is very dangerous. Non-professionals should not go down to prevent accidents.

Second, the dredging method

1. winch dredging

First, use bamboo pieces to pass through the pipeline to be cleaned, and then twist the wire rope back and forth with winches on the inspection wells at both ends of the pipeline, so that the sludge is pushed into the downstream inspection wells by cleaning tools. There are three kinds of winches: manual, electric and electric, and there are many kinds of cleaning tools, which are selected according to the pipe diameter and user's needs. This method is suitable for pipelines with various diameters, especially for pipelines with serious siltation and dense silt bonding.

Disadvantages of winch dredging: it needs to be done manually to transport bamboo chips from one wellhead to another, and the harsh working environment underground brings great inconvenience to the work and easily leads to safety accidents.

2. trench soldiers

The desliming device is used for rigid sealing between the same pipes, which passes through the pipes as a jet under the action of air or liquid pressure, and at the same time removes foreign bodies in the pipes. This method requires smooth and regular pipe wall without excessive silt, so it is mostly used for dredging nuclear energy and industrial metal sewage pipes.

A similar pneumatic ditcher uses compressed air to transport the dredger from one manhole to another, and then the winch pulls the wire rope at its tail to open the wing, and the mud is scraped out of the pipeline with the dredger. Another kind of flexible shaft ditcher is powered by motor or automobile engine, which is transmitted to the digging tool through the flexible shaft. The rotation of the flexible shaft makes the dredging tool rotate and move forward, and the silt is loosened and scraped into another inspection well.

3. High pressure water jet

A widely used dredging method is to use a high-pressure water sprayer equipped with a large water tank, an electric pipe winder, a high-pressure water pump and a water nozzle. During the operation, the automobile engine drives the high-pressure pump to pressurize the water and send it to the water nozzle. The reaction force generated by its backward injection makes the water nozzle and rubber hose move forward in the opposite direction, and at the same time cleans the pipe wall. When the nozzle reaches the downstream inspection well, the motorized winch will retract the hose, and the water nozzle will continue to spray water to flush the residual sediment to the downstream inspection well and be sucked away by the mud suction truck.

This method can be applied to pipelines with various shapes and specifications. Due to the cost and scouring effect, it is usually limited to pipelines with a diameter less than 130cm, and the cost of cleaning water is relatively high. In addition, the influence of mixed sediment particles in high-pressure water jet on the pipe wall can not be ignored.

4. Scouring and dredging

Due to the limitation of manhole size, the components of the whole device must be assembled in the sewer. When working, sewage accumulates in the upstream of the device, and when the sewage reaches a certain height, it will form a water flow in the front of the device to remove sediments. Once enough sediment is washed away, the equipment will move a few centimeters downstream, and the advantages of this method are obvious.

Disadvantages of scouring and dredging: relatively large workload must be completed in sewers. A similar method is to use locally installed facilities, such as sewer gates, for scouring and dredging.

3. Help: Ways and means of dredging, cleaning, dredging and dredging the drainage culvert in Chengdu.

Yonghua Sewage Company1388,2198,474 Based on many years of on-site construction experience, this paper introduces the methods and methods of dredging culverts.

A culvert is a passage where a road or railway intersects a ditch, so that water can flow under the road. They have the same function as bridges, but usually have smaller apertures and shapes, such as pipes, boxes and arches. In addition, the culvert is also a cave-type water conservancy facility with a gate to adjust the water volume.

According to the structural form, it can be divided into circular tube culvert, arch culvert, slab culvert and box culvert. After a period of use, silt impurities precipitate, which affects flood discharge and drainage. Dredging and dredging should be carried out regularly. Precautions and construction methods of culvert dredging and cleaning The vertical height of drainage ditch entering culvert and the length of culvert determine the construction difficulty and harmful gas concentration.

Workers should wear gas masks when entering culvert operations and pay attention to ventilation and exhaust. According to years of construction experience, workers observe whether there are explosive gas bottles, highly corrosive impurities and chemical wastes while cleaning impurities.

The culvert construction method should be determined according to the type, length and depth of culvert impurities and the actual situation on site. For example, the pure mud in the culvert can be extracted by high-pressure washing and dirt suction vehicle.

If there are many impurities, slag and branches in the culvert, it can be cleaned manually and transported by electric hoist. In short, it is safe, convenient and fast according to the actual situation.

4. How to write the tender announcement of culvert dredging project

Buy the tender, do not upgrade), and generate the tender (pay attention to the operating instructions of "tender preparation software", encryption dog); 2. Install "tender preparation software"; 3, import the tender documents, several copies); 5. After compilation, it is imported into the locally installed "tender compilation software", and the tendering agency is not responsible for the consequences caused by the problems in this link (in fact, there is something wrong with their system.

Because it is too complicated, there will be problems in the process of importing the bidding agent system, especially if there are not too many levels: 1, which will be uploaded to the bidding agent system through the network (encryption dogs are needed). Note: Because the bidding agency has restrictions on the size of the whole bidding document (within 50 megabytes or other), it is best to go to the third and fourth floors, and the file directory structure should not be too complicated; 6; 2. The pictures in the bidding documents, especially those in the business documents, should not be too big and need to be properly handled; When I first bid for this kind of target, the bidding documents were well written, but I just didn't bid. )

4. After import: Please consult the tendering agency for details. (Must have: tender preparation software, electronic tender; 3. Upload the technical documents as soon as possible, and the key business information can be uploaded on the day of bid opening, so as to avoid rock the boat and the main structure of the bidding documents (which is convenient for experts to score); 4. Preparation of bidding documents: Prepare bidding documents in word according to the structure generated in the bidding document preparation software (the structure of bidding documents in the bidding document preparation software determines how to divide your word documents into volumes, and the bidding information will be automatically generated in the bidding document preparation software, and there are some incomprehensible and unclear places in this process.

5. How to install the trap head of toilet basin?

Installation method of water trap bent head of toilet;

1. According to the sewage outlet where the product is installed, reserve the sewer pipe at an appropriate position far away from the wall, and determine the distance between the entrance of the sewer pipe and the ground.

2. The depth of the pit reserved for installing the squatting pan under the ground is greater than the height of the toilet.

3. Put the connecting rubber plug into the water inlet hole of the squatting pan and clamp it. Coat a layer of glass glue or putty on the outer edge in contact with the water inlet of the squatting pan, and insert the glue into the water inlet to make it seal well with the rubber plug to prevent water leakage.

4. Paint a layer of glass glue or putty on the edge of the water outlet of the squatting pan, screw it into the inlet of the sewer pipe, and erect the toilet horizontally with cinder or other fillers.

5, open the water inlet system, check whether there is any leakage at each joint, if there is any leakage, check the situation of each joint. Until the problem is solved.

6. After checking that there is no water leakage at each joint, fill the periphery of the toilet with fillers, and at the same time, fill the contact surface between ceramics and cement mortar with elastic materials such as asphalt or linoleum above 1cm. Fix the squatting pan on the horizontal plane with cement mortar, and then spread the bathroom floor tile on the cement surface after it is stable and firm. Try washing it, and use it if there is nothing unusual.