Be familiar with drawings, materials and relevant national or industrial construction, acceptance, specification standards and specification drawings; Prepare construction organization design or construction plan and disclose to construction personnel; Put forward the data plan to the data competent department, and do a good job in warehouse out, acceptance and storage; Prepare construction machinery, tools, measuring tools, etc; Do a good job in the inspection of subdivisional drawings and the work related to change, and prepare the processing site and warehouse; According to the practical situation of pipeline engineering devices, reasonably stop the plane layout of the construction site, and sensitively select the construction organization modes such as sequential operation, flow operation, interleaving operation, etc.
2. Data and equipment management
(1) The main data, waste and semi waste products, accessories, appliances and equipment used in the construction pipeline project must have Chinese quality certificates, and the specifications, models and performance test reports should conform to the national technical specifications or design requirements. Inspection and acceptance shall be carried out when entering the site, which shall be checked and confirmed by the supervising engineer.
(2) All data shall be checked for type, specification and appearance when entering the site. The package shall be in good condition without scratches and external impact damage.
(3) The main appliances and equipment must be provided with complete device operation instructions. During transportation, storage and construction, effective measures shall be taken to avoid damage or corrosion.
(4) Before valve installation, the strength and tightness test shall be stopped according to the standard request, and the test shall be 10% of the quantity of each batch (the same brand, the same model, and the same specification), and not less than one. The strength test and tightness test shall be carried out one by one for the closed valves installed on the main pipe to cut off. The strength test pressure of the valve is 1.5 times of the nominal pressure, and the tightness test pressure is 1.1 times of the nominal pressure.
(5) The calibration and verification of flow meters and pressure gauges used in the pipeline shall be stopped, and the safety valve on the equipment and pipeline shall be stopped by the qualified unit for setting pressure adjustment and sealing test according to the requirements of the design documents. In case of special requirements, other performance tests shall also be stopped. The calibration of safety valve shall be recorded and lead sealed, and a calibration report shall be issued.
(6) Stop the device after confirming that there is no air leakage after the air leakage inspection is stopped for pipeline plugging. Bleed completely after inspection. Connect the above accessories and rubber hoses to confirm the length of use, and reserve sufficient size. Use thin plastic rope to bind them in five sections. Tie the top sling and the end sling with ropes. The diver went down the well and pulled the end sling onto the rope for launching. When a diver dives into the pipe, he first checks whether the pipe wall is flat and free of sharp protrusions within 3 meters. When he dives into the pipe, he will use a rope to drag 2.5 meters into the pipe to fully and completely unfold. The diver starts to inflate the well. The inflation is completed in five times, and each time the pressure is increased by 0.02 MPa. The pointer of the pressure gauge reaches the regular pressure to check whether the water level downstream of the pipe drops. If the water level in the pipeline has dropped and is still falling, clarify that the plugging effect is obvious and continue to check until there is no water leakage. If the water level in the pipeline does not drop obviously and keeps at this level, 2/3 divers must be deflated to check whether it can be opened for further disposal. After use, it can be completely deflated and gradually pulled out for correct storage.
3. Pipeline surveying and setting out
(1) Before measurement, the handover of measurement benchmark shall be stopped with the establishment unit (or supervision unit). The measuring instruments used shall be verified or calibrated to be qualified and within the validity period, and meet the measurement accuracy requirements.
(2) Before pipeline construction, careful drawing review should be stopped. If possible, BIM technology can be used to establish a three-dimensional model to find problems in advance and prevent collisions between pipelines.
(3) Before pipeline construction, on-site measurement and setting out shall be stopped according to the construction drawings to confirm the elevation and position of the pipeline and its supports and hangers, so as to avoid exceeding the standard due to accumulated errors. For example, before the vertical pipeline in the tube well is piped, the field measurement should be stopped to prevent the accumulated error from causing the elevation deviation of each layer.
4. Cooperate with civil works to reserve and embed
(1) Before reservation and embedment, get familiar with the design documents and technical standard requirements, check the divergence between the civil engineering drawings and the device drawings, check the positions, styles and dimensions of the prefabricated parts and reserved holes in the field practice, and cooperate with the civil engineering construction to timely do a good job in the reservation of various holes or the embedding of embedded pipes and prefabricated parts, so as to ensure that the reservation and embedment are correct.
(2) Waterproof measures shall be taken if there are pipes passing through the external walls of open rooms or open structures. For buildings with strict waterproof requirements, flexible waterproof sleeves must be used.
(3) All or plastic sleeves shall be set when the pipe passes through the floor. The top of the casing installed in the floor shall be 20m higher than the decoration air. The top of the casing installed in the bathroom and kitchen shall be 50mm higher than the decoration ground. The bottom shall be flat with the floor bottom. The joints between the casing and the pipeline should be filled with flame retardant dense materials and waterproof ointment, and the end surface should be lubricated.
(4) Metal or plastic sleeves shall be provided when pipes pass through walls. Both ends of the sleeve shall be flush with the finish. The gap between the sleeve and the pipe should be filled with flame retardant and dense materials, and the end face should be lubricated.
5. Pipe support manufacturing device
(1) Pipe supports, hangers and brackets shall be manufactured in accordance with the design documents and the rules of the current specifications, strictly control the welding quality of pipe supports and select appropriate structural methods, such as fixed supports, guide supports, sliding supports, butterfly valve hangers, seismic supports, etc.
(2) When setting up the pipe support, the field surveying and setting out shall be stopped, and the common comprehensive support shall be preferred. The device position shall be correct, and the embedding shall be flat and firm. Ensure that the pipelines and professional pipelines are properly planned on the supports, and the centerline and elevation of the pipelines meet the requirements of the design drawings.
(3) When pipe supports are installed, they should be in close contact with the pipe, with reasonable spacing and firm fixation. The sliding direction or heat shrinking direction should meet the standard requirements.
(4) Indoor water supply metal riser pipe support setting: no less than one pipe support must be set for each floor with a floor height of less than or equal to 5m, and no less than two pipe supports must be set for each floor with a floor height of more than 5m. The location of the device is symmetrical. The height of the pipe support is 1.5~1.8m from the air. The pipe support setting height in the same area should be different.
(5) Trench type connection degree Steel pipe supports and hangers shall be set on both sides of pipe valves (rigid valves, flexible valves, branch valves) and on both sides of upstream and downstream connection valves of three-way, four-way, elbow, reducer and other pipe fittings. The clear distance between supports and hangers and valves shall not be less than 150mm and not more than 300mm.
(6) When metal pipe supports are used for plastic pipes, non-metallic pads or sleeves shall be lined between pipes and supports.
6. Pipe prefabrication
For pipeline prefabrication, construction sketches such as pipeline branching, pipeline turning, pipeline reducing, reserved pipe orifice, valve position, etc. shall be drawn according to the design drawings. After on-site mapping and setting out, accurate dimensions shall be confirmed, and records shall be made on the construction sketches. Before prefabrication, the pipe sections shall be numbered in groups, and prefabrication shall be stopped based on the principle of "prefabrication first", Convenient transportation shall be considered for pipelines not prefabricated on site. Pipeline quality inspection and primer painting shall be stopped at the same time during pipeline prefabrication.