The people who have some knowledge of the heating system know that the heat extension or the temperature stress of the heating pipe can cause the deformation or damage of the pipe. At this time, it is necessary to set up a device on the pipe, such as compensator, rotary compensator or casing compensator, which can compensate for the thermal elongation of the pipeline, so that the stress of the wall and the force acting on the valve or bracket structure can be reduced. When installing a rotating compensator, we should pay attention to the following points:
1, before the installation, check the outer end of the inner tube to reveal the lid, to meet the design requirements.
2. The rotary compensator is welded directly (or flanged) on the pipe, and the protective compensator is used when welding. Pay attention to the installation of the medium flow direction indicator specified by the compensator.
3, pipeline compensator and maintain concentric, half of rotation angle shall be half of the pre offset or delta L are pre offset;
4, near the ends of the right compensator location should be a reliable guide bearing, ensure operation free expansion of pipe bracket should be in accordance with the amount of expansion and the safety margin and consider the use of appropriate temperature and temperature for installation;
5, the end pipe welding should meet the requirements of GB985-88 and GB986-88.
6. When the cold season is welded, the end and end pipe of the steel pipe should be preheated.
7, check whether the installation after the gland bolts uniformly tighten (not too tight, as long as the uniform), then the section pressure seal test, qualified rear can undertake system pressure test, the test can be 1.5 times the working pressure or by the design department to provide the data for the pressure test, the test time for three times:
The first step to the 1 / 3: work pressure, charge off the Watergate, observe whether there is a drop of water, if there is leakage, please stop leakage can be tightened slightly at;
The second time: increase pressure to work pressure, stop pressure to observe, whether there is leakage phenomenon;
The third time: increase to 1.5 times the working pressure. After 10min, if the pressure remains constant, the strength test is qualified. When the pressure is reduced to working pressure, it will last for 30min. If the pressure remains unchanged, it will be qualified.
Note: whether the rotary compensator is whole or sectional pressure test, the tail steel pipe of pipeline must be fixed. The general method is to use special fixed support to connect with the piers, so as to avoid the pipeline displacement and destroy the whole pipeline correctly to compensate the gap. In general, as long as the pipe is installed correctly, it will be successful at one time.