Before installation, the drum should be subjected to hydraulic pressure test on the left and right misaligned air shafts one by one; the test pressure is 0.2 MPa, the pressure is maintained for 15 minutes, and the air passages are inspected to be incompatible with each other. After the drum is placed in the positive direction, the left and right misaligned air shafts and the filter are assembled; the different degrees of the drum, the left and right misaligned shafts are required to be no more than 0.15 mm, and the drum and the two wrong air shafts are assembled as a whole. Installed on the main bearing, check the level, the deviation must not exceed 0.10mm / m. Before the filter cartridge is installed in the drum, the dirt such as mud and sand on the drum should be cleaned; after the filter cartridge is installed, the whole assembly is placed on the main bearing or the large lathe, and the drum and the filter drum are rounded. The roundness error shall not exceed 0.03 mm, and the amount of swing on both ends of the drum shall not exceed 1 mm. If it is processed on a lathe, it is not necessary to install the left and right misaligned shafts first; in order to prevent the cutting knives from collapsing during machining, the line of the filter ribs should be stuffed with a length of about 15 mm before processing. Wood strip; for φ2550×1900mm filter, 8~12 pieces per line are suitable; φ184×900mm filter, 4~6 pieces per line is suitable.

The gap between the filter and the drum and the gap between the two ends of the drum are sealed with epoxy resin and a rubber plate with a thickness of 0.5 mm to seal the gaps between the drums.