As the saying goes: "Before the soldiers and horses move, the food and grass first", the construction preparation is a very critical process, is the foundation of the subsequent process. In fact, the construction preparation stage is the busiest time for project managers, need to communicate and coordinate with all parties to solve the following problems: the construction of water and electricity; the location of the living area and living water and electricity; the location of the material stacking (not only close to the construction site, but also can not affect the construction of other professions); the location of the warehouse (used to pile up tools and various valves and other auxiliary materials); the extraction of materials (there should be a certain amount of spare parts because each project will have Material extraction (to have a certain amount of margin, because each project will have a margin, so not according to the drawings on the size of the extraction, the demand for large fittings extraction should be more than a few on the basis of the drawings); material procurement and to determine the time of the material into the field; to prepare for the start of the pre-construction information (technical documents for examination and approval of the table, the report on the commencement of the work, the safety and technical briefings, etc.); the workers for safety education; to prepare for the work of machinery and equipment; special types of workers (such as welders, electricians, etc.) should be certified to the post. In short, the construction preparation is a very tedious work that needs to consider many issues.
2. Cooperate with the civil construction of reserved, buried
In the civil construction must pay attention to cooperate with the civil construction of reserved, buried. Pipes out of the building must be well buried, pipe installation, should be in the middle of the buried parts and pipes welded on the water stop ring, easy to fill in the future processes such as oil hemp. Shear wall above the reserved holes is very important, most of the project after the completion of civil construction, the shear wall is not allowed to open holes on the private. If not reserved, pre-embedded, you need to communicate with the party, supervision, design and other parties to negotiate, adding a lot of unnecessary trouble; at the same time, their own holes will have to add a lot of manpower and material resources. If the machine room in the basement, must pay close attention to the civil construction side of the construction, to avoid the machine room equipment has not yet arrived in the machine room, lifting hole has been closed.
3. Pipe support, hanger production and installation
Support, hanger materials, models must be selected in accordance with the specification requirements, because this involves safety issues, but also the supervision of the most concerned about the place. After the arrival of the material to do a good job of information, please supervise the inspection and signature; support hanger installation, must be rust and then paint; support hanger installation, especially inside the host room support hanger installation should pay attention to a few issues: more than DN200 pipeline try to do the bracket do not do the hanger, to avoid the impact of the building structure; hanger as far as possible to be installed in the beams, do not hit the top, so that the hanger to withstand the shear force, instead of tensile force; Whether it is a bracket or hanger, the crossbar should not be made too long, to avoid too large a span and sagging, so that the host or pump import and export on the soft acceptance of force and deformation.
4. Equipment, accessory inspection
Equipment and accessory inspection is to avoid problems when the system is running. After the arrival of equipment to open the box in the presence of the supervisor, and save the information brought with the box; powered equipment to do stand-alone test run; valves should be sampling to do pressure test, the key position of the valve, such as the bypass valve between the collector and distributor, the host of the import and export of the bypass valve between the valve and the winter and summer conversion valves are best to do the pressure test to ensure that the pressure in the work of the valves can be closed tightly to avoid the impact of the cooling and heating effect. The effect.
5. Piping installation
Piping installation is the most direct process. The project is good or bad, whether it is beautiful or not, all depends on whether the pipeline installation is standardized. Host room piping installation should follow the thick pipe down, thin pipe up, small pipe so that large pipe, pressure pipe so that the principle of pressure pipe. Pipes should be rusted and painted before installation; pipe connection, I think that in addition to the flange and not easy to weld the mouth of the place, the other places try to point first, and finally by the skilled welder unified welding. This not only can make the pipeline to do beautiful, but also can avoid the welder technical unevenness caused by the pressure when the leakage is too much. Host, pump import and export above the valve as far as possible to do in a horizontal line, and so that the valve handle is in a position that is easy to operate. Filters, check valves and other need to add a pad, if it is a rubber pad can be installed directly, if it is an asbestos pad, you should first put the pad into the oil soaked for 24 hours. In addition, the gasket should be installed to press the flange water line to avoid leakage. The host and the pump inlet and outlet installation of the sewage valve should be installed in a line, which is conducive to making a drainage ditch. The highest point of each trip of the pipeline should be installed with automatic exhaust valve to avoid gas storage inside the pipeline, which affects the water circulation. When there is a cooling demand, the middle of the pipeline and the support bracket should be added with anti-corrosion wood bracket, to avoid the occurrence of cold bridge, so that condensation occurs on the support bracket. When installing pipelines, many valves need to be bolted, and when installing the bolts, the flat elastic gaskets should be installed to avoid vibration of the pipeline during operation, and water leakage after a long time when the nut is not tight. If the pipeline needs to be installed above the compensator, pay attention to both ends of the compensator to hit the fixed bracket, so that the compensator can only be before and after the expansion and contraction, but not up and down misalignment.
6. Piping system experiments
Piping system experiments is a process even without supervision can not deceive themselves and others. Do pipeline tightness test, in the steady pressure, not only need to observe the pressure gauge, but also carefully check the welded and threaded joints whether water seepage, do not see clearly the best place to touch with your hand. Because a small amount of water seepage at the interface, the pressure gauge pressure is no significant change, but these small amount of water seepage accumulated over time can damage the ceiling. For condensate piping water test is also essential. From the several projects I have done, the condensate pipe can not be inverted slope of such common sense problems, each project has appeared. If the condensate pipe inverted slope, condensate will overflow from the fan coil condensate tray to damage the ceiling, and maintenance is not only a wind tray, but a trip to the pipeline should be checked, especially in the ceiling inside the maintenance is very difficult, the workload is also very large.
7. Anti-corrosion adiabatic
Piping experiments are completed, it began to do anti-corrosion adiabatic. Insulation is generally used in rubber-plastic materials. Insulation thickness should be selected in accordance with the requirements of the drawings, insulation must pay attention to the insulation pipe and pipe type consistent. If there is a gap in the middle of the insulation pipe and pipe, condensate will exist in the insulation pipe, and over time, it will cause the insulation pipe to open the glue, water leakage. I think when the pipe is installed, you can put the insulation pipe on first and leave the connection port, which not only speeds up construction, saves insulation glue and tape, but also reduces the insulation pipe interface and reduces the leakage point.
8. System flushing
After the completion of the pipeline installation, there will be a lot of welding slag and other debris inside, these debris, if they enter the equipment will affect the life of the equipment, so it is necessary to carry out pipeline cleaning. Cleaning the pipeline must be the host import and export valves shut down, open the bypass, so that the water flow cycle discharged until the discharged water is not turbid, no foam; and then open the filter, clean up the screen.
9. System debugging
System debugging should be commissioned by a full-time commissioning staff to check whether the circuit is correct, whether the valve opens correctly, and then open the water pump, the system is filled with water, open the submersible pump, the system circulating pumps, and finally turn on the host.
The above from the various construction processes talk about some of the precautions. Of course, as a project manager, in each project will encounter different problems, but we must firmly believe that even the most difficult problems will have a solution. We must pay attention to the usual accumulation, the more experience, in the future construction problems will be less; problems, it will be easier to think of ways to solve.