Aluminum Alloy Bicycle Parts Lay Back Seat Post

fay@pride-cnc.com

Block D, Dianlian Science Park, Matian St., Guangming District, Shenzhen 518106, China

+8613477665385

13477665385

Process Measures to Reduce the Deformation of Aluminum Processing

1. Reduce the stress in the hair.

Natural or manual limitations and vibration treatment can partially eliminate the internal stress of the blanks. Pre-processing is also an effective process method. On the fat head large ear of the blank, because of the large margin, so after processing deformation is also large. If the excess part of the blank is pre-processed and the margin of each part is reduced, not only can the process deformation of the later process be reduced, but also after the pre-processing is placed for a period of time, it can also release some of the internal stress.

2. Improve the cutting ability of the tool.

The material and geometric parameters of the tool have an important influence on cutting force and cutting heat, and the correct selection of the tool is very important to reduce the deformation of part machining.

(1) Choose the tool geometry parameters reasonably.

(1) Front corner: in maintaining the edge strength of the conditions, the front corner is appropriately selected erroneity, on the one hand can grind out a sharp edge, in addition can reduce cutting deformation, so that the chip smooth, and thus reduce cutting force and cutting temperature. Avoid using a negative front angle cutter.

(2) Rear corner: the size of the rear corner has a direct effect on the wear of the rear face and the quality of the processing surface. Cutting thickness is an important condition for selecting the rear corner. Coarse milling, due to the large amount of synth, heavy cutting load, large heat, the tool is required to have good cooling conditions, therefore, the rear corner should be selected smaller. When milling, the edge is required to be sharp, reduce the friction between the rear face and the machining surface, reduce elastic deformation, therefore, the rear corner should be selected 1.

(3) Spiral angle: In order to make milling smooth and reduce milling force, helix angle should be selected as large as possible.

(4) Main angle: a proper reduction of the main angle can improve the cooling conditions, so that the average temperature of the processing area decreased.

(2) Improve the tool structure.

(1) Reduce the number of milling cutter teeth, increase the chip space. Because the aluminum material is more plastic, the cutting deformation in the processing is larger, the need for a larger chip space, so the bottom radius of the chip slot should be larger, the number of milling cutter teeth is less good.

(2) Fine grinding knife teeth. The roughness value of the cutting edge of the tooth is less than Ra?0.4um. Before using the new knife, a few gentle grinds should be made in front of and behind the knife teeth with fine oil stone to remove the remaining burrs and slight serrated marks when grinding the blade teeth. In this way, not only can reduce the cutting heat but also the cutting deformation is relatively small.

(3) Strict control of tool wear standards. When the tool is worn, the surface roughness value of the work piece increases, the cutting temperature increases, and the deformation of the work piece increases. Therefore, in addition to the selection of good wear resistance tool materials, tool wear standards should not be greater than 0.2mm, otherwise it is easy to produce crumb tumors. When cutting, the temperature of the work piece should generally not exceed 100 degrees C to prevent deformation.

3. Improve the clamping method of the work pieces.

For less rigid thin-walled aluminum work pieces, the following clamping methods can be used to reduce deformation:

(1) For thin-walled bushing type parts, if the three claws self-center chuck or spring chuck from radial clamping, after processing once released, the work piece will inevitably deform. At this point, a method of axial face tightening with better rigidity should be used. Positioned with the inner hole of the part, make a threaded perforated shaft, which is placed into the inner hole of the part, which is pressed on the end face with a cover and then tightened with the nut back. When processing the outer circle, the clamping deformation can be avoided, so as to obtain satisfactory processing accuracy.

(2) When processing thin-walled sheet work pieces, it is best to choose a vacuum suction cup to obtain a uniform distribution of clamping force, and then a smaller amount of cutting to machine, can be a good way to prevent deformation of the work pieces.

In addition, the filling method can be used. To increase the process rigidity of thin-walled work pieces, media can be filled inside the work pieces to reduce deformation during clamping and cutting. For example, a urea melt containing 3% to 6% potassium nitrate is poured into the work piece, and after processing, the filler can be dissolved and poured out by dipping the work piece into water or alcohol.

4. Reasonable arrangement of operations.

When cutting at high speeds, milling processes often produce vibrations that affect machining accuracy and surface roughness due to the large machining balance and intermittent cutting. Therefore, CNC high-speed cutting process can generally be divided into: roughing - semi-finishing - clear angle processing - finishing and other processes. For parts with high accuracy requirements, secondary semi-finishing is sometimes required before finishing. After roughing, parts can be cooled naturally, eliminating internal stress from roughing and reducing deformation. The amount left after roughing should be greater than the amount of deformation, generally 1 to 2mm. Finishing, part finishing surface to maintain a uniform finishing surplus, generally 0.2 to 0.5mm is appropriate, so that the tool in the process of machining in a stable state, can greatly reduce cutting deformation, obtain good surface finishing quality, to ensure the accuracy of the product.

Hot Tags: aluminum alloy bicycle parts lay back seat post, China, manufacturers, suppliers, factory, wholesale, customized, made in China