Precautions for brass turning

The processing technology of CNC lathes is similar to that of ordinary lathes, but because CNC lathes are one-time clamping and continuous automatic processing to complete all turning processes, the following aspects should be paid attention to.

1. Reasonable choice of cutting amount: For high-efficiency metal cutting processing, the processed material, cutting tools, and cutting conditions are the three major elements. These determine the processing time, tool life and processing quality. The economical and effective Machining method must be a reasonable choice of cutting conditions. The three elements of cutting conditions: cutting speed, feed rate and depth of cut directly cause tool damage. With the increase in cutting speed, the temperature of the tool tip will rise, which will cause mechanical, chemical, and thermal wear. Cutting speed increased by 20%, tool life will be reduced by 1/2. The relationship between the feed condition and the wear on the back of the tool occurs in a very small range. But the feed rate is large, the cutting temperature rises, and the back wear is large. It has less influence on the tool than cutting speed. Although the influence of cutting depth on the tool is not as large as the cutting speed and feed rate, when cutting at a small depth of cut, the material to be cut will produce a hardened layer, which will also affect the life of the tool. The user should select the cutting speed to be used according to the processed material, hardness, cutting state, material type, feed rate, depth of cut, etc. The selection of the most suitable processing conditions is selected on the basis of these factors. Regular, stable wear and longevity are the ideal conditions. However, in actual operations, the choice of tool life is related to tool wear, dimensional changes to be processed, surface quality, cutting noise, and processing heat. When determining the processing conditions, it is necessary to conduct research according to the actual situation. For difficult-to-process materials such as stainless steel and heat-resistant alloys, coolants or blades with good rigidity can be used.

2. Choose a tool reasonably: (1) When roughing, choose a tool with high strength and good durability, so as to meet the requirements of large back-grabbing and large feed when roughing. (2) When finishing turning, choose high-precision and durable tools to ensure the requirements of machining accuracy. (3) In order to reduce the time of tool change and facilitate tool setting, machine-clamped knives and machine-clamped blades should be used as much as possible.
3. Reasonable selection of fixtures: (1) Try to use general fixtures to clamp the workpiece and avoid using special fixtures; (2) The parts positioning datum overlaps to reduce positioning errors.
4. Determine the processing route: The processing route is the movement track and direction of the tool relative to the part during the processing of the index-controlled machine tool. (1) It should be able to ensure the machining accuracy and surface roughness requirements; (2) The processing route should be shortened as much as possible to reduce the tool idle travel time.
5. The connection between the processing route and the machining allowance: Under the condition that the CNC lathe has not yet reached the popular use, the excessive allowance on the blank, especially the allowance containing the forging and casting hard skin layer, should be arranged on the ordinary lathe for processing. If you must use a CNC lathe to process, you need to pay attention to the flexible arrangement of the program.
6. Main points of fixture installation: The connection between the hydraulic chuck and the hydraulic clamping cylinder is realized by a pull rod. The main points of clamping the hydraulic chuck are as follows: First, use a moving hand to remove the nut on the hydraulic cylinder, remove the pull tube, and remove it from the back of the spindle Pull it out, and then use a moving hand to remove the chuck fixing screw to remove the chuck.