(1) It is matched with the radial ball bearing 210, the outer spacer ring and the inner spacer ring between the D grade (when two 46210, D grade angular contact ball bearings are used, the spacer ring is not required), and the 20kg is applied to the bearing. The axial force determines the height difference between the inner and outer spacers, and the parallelism of the two ends of the inner and outer spacers is less than or equal to 0.003ram.

(2) Install the rear bearing seat, rolling bearing, bearing outer spacer and inner spacer on the main shaft, and then install the above-mentioned assembly into the grinding head body.

(3) Place the grinding head body vertically (the cone of the spindle faces upwards) without sliding bearings, and measure the radial runout of the spindle ≤0.1mm. Attach the dial indicator holder to the end of the spindle, with the needle pointing to the inner diameter of the front bearing seat, and measure the coaxiality between the spindle and the front bearing seat ≤0.02mm. If the measured value is out of tolerance, the inner and outer spacers of the bearing should be readjusted, and the rear end of the grinding head body should be ground until the requirements are met.

(4) The main shaft and sliding bearing are equipped with scraping. Attention should be paid to the scraping: ①The red lead powder or red ink oil applied should not be too thin. It should be evenly applied. ②When scraping the sliding bearing with a scraper, the radial force is 10kg, and the gap between the main shaft and the sliding bearing seat is adjusted to 0.02—0.025mm.

(7) The sliding bearing is filled with lubricating oil as required, and silk cloth should be used to filter the filling.

(8) Place the grinding head body horizontally and run it idling for 4 hours to allow the main shaft and sliding bearing to get full running-in, and measure the temperature rise of the bearing ≤30℃.

(9) Drain all the lubricating oil in the grinding head body. Refill the lubricating oil as required. Silk cloth should be used for filtering when filling oil. It is necessary to spot check the cleanliness of the lubricating oil. According to the weight method, the impurities and dirt should not exceed 200mg.

(10) Adjust the gap between the main shaft and the sliding bearing seat to 0.03~0.04mm, and start a test run. Measure the radial runout of the spindle cone and the axial movement of the spindle. The old machine tools should be less than or equal to 0.01ram, and the new ones should be less than or equal to 0.005mm.