Improvement of C620 Spindle Front End Bearing

In the past, traditional C620 lathes were equipped with sliding bearings on their spindles. While sliding bearings have advantages such as a simple structure, easy manufacturing, low cost, smooth operation, and resistance to shock and vibration, they are no longer suitable for modern high-speed, high-precision, and high-efficiency cutting tools. Additionally, these bearings are difficult to repair after wear, leading to poor surface finish and accuracy of machined parts, as well as low productivity. To address these issues, the bearing system of the C620 lathe spindle was redesigned and improved. The specific steps involved in the modification are as follows (refer to the attached drawing): 1. **Modification of the Front Bearing Hole of the Headstock** The front bearing bore of the headstock was machined to Ø150K6. A Ø151 mm hole, 55 mm in length, was also created at the left end of the bearing bore to facilitate the installation and removal of the bearing. In addition, a Ø16 mm hole was drilled to make it easier to fasten screw 5.  *1. Headstock 2. Adjusting Nut 3. Spindle 4. Nut Stop Pad 5. Fastening Screw 6. 3182120 Bearing 7. Bearing Cap Pressure Ring 8. Improved Bearing Cap* 2. **Modification of the Spindle** A M100×1.5 mm thread was machined on the spindle according to the dimensions and position shown in the diagram. The adjusting nut 2, nut stop pad 4, and fastening screw 5 were then installed. A 1:12 taper was also machined on the spindle to match the inner taper hole of bearing 6. The bearing cap 8 and the bearing cap pressure ring 7 were machined accordingly, and the original sliding bearing adjustment nut was re-machined to fit the dimensions of the new bearing cap 8 (unlabeled dimensions refer to existing parts from the original design). The original bearing cap pressure ring was also modified to match the size of the new pressure ring 7. 3. **Adjustment of Spindle Axial Fluctuation and Radial Clearance** - The axial misalignment of the spindle was adjusted using the adjusting nut at the rear end of the spindle. The measured misalignment of the spindle shoulder support surface should be 0.015 mm. - The radial runout of the centering journal of the spindle was adjusted using the adjusting nut 2, ensuring that the bearing 6 has a slight radial clearance. The radial runout of the spindle centering shaft head should not exceed 0.02 mm. After the modifications, the machine tool's accuracy was tested and met the following standards: - Radial runout of the spindle centering shaft head: 0.01–0.03 mm - Axial movement of the spindle: 0.015 mm - Parallelism of the spindle axis to the slide movement: 0.02 mm over 300 mm (in both vertical and horizontal planes) - Perpendicularity of the cross-slide movement to the spindle axis: 0.02 mm (concave) over 3000 mm - Height deviation between the headstock and tailstock tips: 0.03 mm - Roundness of a 300 mm long finished shaft: 0.02 mm - Cylindricity of the same shaft: 0.03 mm - Flatness of the end face of the finishing carriage: 0.02 mm (concave) - Surface roughness of the machined part: Ra 6.3 to 3.2 μm All these values comply with the JB2670-82 standard for metal cutting machine accuracy. As a result, the performance and quality of the modified C620 lathe have significantly improved compared to the original version.

Continuous Belt Type Vacuum Packaging Machine

Continuous Belt Type Vacuum Packaging Machine, Transmission Type Vacuum Packaging Machine,Conveyor Belt Type Vacuum Packing Machine,Belt Type Vacuum Packaging Machine

ZHUCHENG YIKANG FOOD PACKING MACHINERY CO., LTD. , https://www.yikangmachinery.com