How to choose a good CNC machining supplier?
When you are purchasing cnc machining parts, in many cases we will not know how to choose the right supplier. We must consider not only the price, but also the quality, delivery, service and other factors. I hope that our article will give you some help.
(1) Choose high reliability: it means that when the machine tool performs its function under the specified conditions, it runs stably for a long time without failure, that is, the mean time between failures is long; even if it fails, it can be restored in a short time and put into use
(2) Choose machine tools with reasonable structure, well-manufactured, and mass-produced machines. Generally, the more users, the higher the reliability of the CNC system.
However, the quality of a CNC part reflects not only the strength of a manufacturer, but also his handling of some details. For CNC machining parts, if the manufacturer does not handle it well, the processed product is unqualified. What should the manufacturer pay attention to in order to avoid processing failures and reduce costs during processing?
I. Burrs on the surface of the workpiece
This point is easily overlooked by many businesses. For a part, CNC lathe processing parts are completed by equipment, then there will be problems during injection molding, and this burr is also generated at this time, if it is not polished in time If trimmed, this part can only be scrapped, otherwise it will affect other links during use.
For CNC lathe machining parts, its accuracy is very strict. Only the required accuracy can be used. The accuracy criterion is mainly based on the part's ability to control the size and the resulting tolerance. Within the allowable fluctuation range, if the tolerance is exceeded, the part is unqualified and cannot be put into future production and sales.
III. Analysis of test results
Parts need to undergo performance testing before leaving the factory. If the performance is qualified, they will be shipped. If they are not qualified, some of the reasons should be analyzed, so as to avoid mass scrapping. Manufacturers in the processing industry basically deal with it in this way. They will make a certain quality control chart based on the performance of many companies to analyze the reasons.
1. Attention should be paid to the CNC machining:
(1) For the current economic CNC lathes in my country, ordinary three-phase asynchronous motors are used to achieve stepless speed change through frequency converters. If there is no mechanical deceleration, the spindle output torque is often insufficient at low speeds. If the cutting load is too large, It is easy to get stuffy, but some machine tools have gears to solve this problem well;
(2) As far as possible, the tool can complete the processing of a part or a work shift. In the finishing of large parts, special attention should be paid to avoid changing the tool in the middle to ensure that the tool can be processed in one time;
(3) When using CNC turning to turn the thread, use a higher speed as much as possible to achieve high-quality and efficient production;
(4) Use G96 as much as possible;
(5) The basic concept of high-speed machining is to make the feed exceed the heat conduction speed, so that the cutting heat is discharged with the iron filings to isolate the cutting heat from the workpiece, and to ensure that the workpiece does not heat up or does not heat up. Therefore, high-speed processing is selected very high The cutting speed is matched with the high feed and the smaller back-grab is selected at the same time.
2. Vibration and tool breakage often occur during grooving. The fundamental reason for all of these is the increased cutting force and insufficient tool rigidity. The shorter the tool extension length, the smaller the clearance angle, and the larger the area of the blade, the better the rigidity. The cutting force can be increased with the greater the cutting force, but the greater the width of the groove tool, the cutting force it can bear will increase correspondingly, but its cutting force will also increase. On the contrary, the smaller the groove tool, the smaller the force it can bear. Its cutting force is also small.
3. Reasons for vibration during car trough:
(1) The extension length of the tool is too long, resulting in lower rigidity;
(2) The feed rate is too slow, which will cause the unit cutting force to increase and cause a large vibration. The formula is: P=F/back-cutting amount*f P is the unit cutting force, F is the cutting force, and the speed is too fast Also vibrate the knife;
(3) The machine tool is not rigid enough, which means that the tool can withstand the cutting force, but the machine tool cannot withstand it. To put it bluntly, the machine tool does not move. Generally, the new machine does not have this kind of problem. The machine with this kind of problem is either old. Either the machine killer is often encountered.
