How to judge the specification and model table of pneumatic butterfly valve?
The welding of supports and hangers shall be performed by qualified welders, and there shall be no defects such as missing welding, under welding or welding cracks. When the pipe is welded with the support, there shall be no undercut, burn through and other defects. For pipes without thermal displacement, the suspender shall be installed vertically; for pipes with thermal displacement, the lifting point shall be installed in the opposite direction of displacement according to 1 / 2 deflection of displacement, as shown in Fig. 8. For two pipes with opposite or unequal thermal displacement directions, the same suspender shall not be used unless specified in design documents. The sliding surface of the guide bracket or sliding support shall be smooth and smooth, without deflection and jamming. The installation position should be offset from the center of the bearing surface to the opposite direction of displacement, and the offset should be 1 / 2 of the displacement or in accordance with the provisions of the design documents. The insulation layer should not hinder its displacement. The form and position of supports and hangers shall be checked one by one according to the provisions of design documents after the installation of hanger with thermal displacement pipe is completed. For the pipeline with thermal displacement, the following inspection and adjustment shall be carried out on the supports and hangers in time during the thermal load operation: the displacement direction, displacement value and guiding performance of the movable supports and hangers shall meet the provisions of the design documents, the pipe supports shall not fall off, the fixed supports and hangers shall be firm and reliable, and the installation elevation and spring working load of the spring supports and hangers shall comply with the provisions of the design documents, The limit plate of spring support shall be removed before thermal load operation.
Pipe supports and hangers with strong vibration shall be constructed according to the following requirements: asbestos cloth, asbestos valve plate, hard rubber plate or hard wood pad with anti-corrosion treatment shall be added on the fastening surface of pipe support and pipeline, and the fastening nut for fastening pipe support shall be equipped with spring washer, lock washer or fastening nut, Pipe supports shall not be fixed on floors, walls, elastic steel structures and vibrating equipment or supports. 3. Other precautions: the installation accuracy of pipelines and equipment shall comply with relevant regulations. When there is alignment deviation, it is strictly forbidden to use pneumatic valve to make up for it, especially the waveform pneumatic valve is not allowed to be subjected to torsion. During the installation of pneumatic valve, the stress condition under hydrostatic test condition must be considered, and the support and hanger arrangement of pneumatic valve shall be mainly checked to see if it meets the design requirements. Before pressure test, carefully check whether the supports and hangers are installed correctly and whether the welding of supports and hangers meets the design requirements. During the pressure test, the change of compensator should be observed at any time, so as to take preventive measures in advance to prevent the deformation of pneumatic valve caused by pipeline instability, thus losing its due role.