1. The type of cutting fluid directly affects the roughness of the machined hole wall. In actual production, the selection of cutting fluid is unreasonable, which often directly leads to the decrease of the roughness of the machining hole wall. In our actual processing, when reaming holes, if adding emulsions with different concentrations, the surface of the workpiece hole wall is as smooth as a mirror surface, the surface and roughness values are very small, and the Ra can reach 0.8 ~ 1.6mm; if adding total loss The management system can use oil, the surface of the workpiece material turns black, and the surface roughness is slightly worse than that of the emulsion, and the Ra value is generally about 1.6mm; adding to the aqueous solution, the surface roughness value of the workpiece structure is the largest, and the Ra value is generally 3.2 mm or so. The practical results show that: when the required level of hole wall roughness value is very low, extreme pressure emulsion should be added as the cutting fluid when reaming; The roughness is basically required by the enterprise, and the total loss control system engineering oil demand can be selected as the cutting fluid.
2. The concentration of cutting fluid directly affects the lubrication performance during processing, so the concentration of cutting fluid is a process parameter that needs to be paid attention to in actual production, that is, each processing equipment needs to set a concentration index. That is, the highest concentration demand value in the coolant supply system is selected to ensure that the tool requirements of the processing steps with high demand are met. For example, the concentration of the cutting fluid when machining aluminum alloys is generally 8% to 10% (<10% to 12% for special purposes). tool concentration requirements). The concentration of processed cast iron is generally 5% to 7%.
3. The cleanliness of the cutting fluid, due to the small machining allowance of reaming, the shallow chip groove of the tool, and the small coolant hole in the tool holder, so the cleanliness of the cutting fluid is required to be high. In our production, the same two reaming devices process the same content. One day, the reaming quality of one device suddenly becomes very poor, and there is a rough phenomenon. The hole is a two-level hole with a gap in the middle. There is also the case of large upper and small lower, and the quality of reaming of another equipment is still very good. We looked for the reason from the process parameters, the spindle jumped, and found no problem. Considering whether the cutting fluid is related to the cutting fluid, we first tried to increase the cutting fluid concentration from 8% to 10%, but the effect was still not good, and then tried to replace the cutting fluid. After cleaning the cutting fluid backwash filter, the reaming hole was tested, and the hole wall accuracy met the requirements, indicating that the cleanliness of the cutting fluid directly affects the reaming accuracy.
In actual production, the cleanliness of the coolant also directly affects the use of tools. For example, some internal coolant holes cool reaming knives because the coolant is dirty and the internal coolant holes are clogged. Once the coolant holes are clogged, the debris often does not drain properly, allowing the hole wall hair to be processed and the workpiece to be scrapped. Also, dirty coolant can affect the tool and shank. Because the coolant is too dirty, the chip sticks to the shank, which makes the shank torque rise and twist and damage. The mouth eventually leads to failure consequences, the tool holder cannot be used normally, and the workpiece must be scrapped. 4. The temperature of the cutting fluid, the lubrication effect is that the cutting fluid penetrates into the contact material surface of the tool and the workpiece without forming a thin oil film, which can reduce the friction between the tool and the cutting surface of the workpiece, and reduce the incidence of chips and workpieces. Sticking of tools and generation of built-up edge. To form different oil films, the cutting fluid must develop a certain viscosity in China, but temperature has an unavoidably neglected effect on the viscosity. As far as the whole day is concerned, with the change of indoor space environment and temperature, there will be some social changes in the temperature of the coolant. At the same time, the temperature data of the cutting fluid in the equipment will also change greatly due to the continuation of the processing time. , Therefore, the control system of environmental design temperature is conducive to improving the quality of processed products, especially for finishing; in terms of the four seasons of the year, the temperature difference between summer and winter is larger, and the emulsion with the same effective concentration has a viscosity in summer. The viscosity becomes larger in winter. Therefore, when choosing an emulsion, one with a higher viscosity should be used in summer, and a slightly smaller viscosity should be used in winter.
