In the machining industry, thin-walled workpiece due to poor rigidity, in the turning process is prone to vibration and deformation, its shape and position tolerance and dimensional tolerance can not be guaranteed, if the solution is not appropriate, even the processing can not be carried out.
1. Processing problems
The machining of thin-walled parts is a difficult problem in turning, because the thin-walled parts are rigid and weak, so it is easy to deform in the process, which makes the parts ' shape and position error increase, and it is difficult to ensure the machining quality of parts.
For this reason, the strict requirements are put forward for the clamping of thin-walled parts, the reasonable selection of cutting tools and the choice of cut dosage.
Machining analysis of thin-walled stainless steel pipe in machinery industry Our thin-walled stainless steel tube is a product of the nozzle heat impact casing, the workpiece belongs to the large diameter thin-walled workpiece, pipe diameter of 292mm, material z2cnd17-12 control nitrogen stainless steel, wall thickness requirements 4mm, the total length of the workpiece more than 550mm (leaving a clamping allowance), roundness requirements 0.05mm,
All surface roughness values are ra=6.3μm, which determines that the workpiece's precision coefficient is very high.
2. Processing technology development
(1) Increase the process chuck, so that the length from the finished product 550mm lengthened to 610mm.
(2) Dividing the processing stage: ① roughing phase. Use coarse car and coarse boring to remove the allowance.
Roughing, the back to eat knife and feed can be larger; finishing, the back to eat knife in general in 0.2~0.5mm, feed in general in 0.1~0.2mm/r, or even smaller, cutting speed 6~120m/min, precision cars with as high a cutting speed, but not too high. ② half processing stage. For the main surface of the finishing preparation, the completion of a number of secondary surface processing, the use of semi-precision vehicle processing before finishing to achieve the necessary precision and processing allowances. If the pipe is clamped on the chuck force too large, it will make the thin-walled parts deformation, resulting in the roundness error of the parts. If the chuck is not tightly clamped, it is possible to make the parts loose and scrap when turning. When we take a rough car, we clamp it tight, and the car is loosely clamped to control the deformation of the part. Semi-precision processing stage back to eat less knife, so that the internal stress of thin-walled stainless steel tube release, reduce the amount of precision processing deformation.