How to choose WEDM machine tool?

WEDM machine tool is developed on the basis of WEDM machine tool. It uses repeated machining of the same part to achieve higher precision and better surface quality than WEDM machine tool.

1.2 Why is it called "middle line"?

The term "intermediate wire feeding" itself is not scientific, it is just a general term for machine tools with reciprocating wire feeding and multiple cutting functions. It is obviously different from fast wire cutting machine and slow wire cutting machine. Strictly speaking, there is no intelligent control, only a single multiple cutting function, which cannot be called "wire feeding". It is precisely because of the unscientific name of "wire feeder" that a loophole has been drilled in the fake wire feeder bed, which has caused troubles to users in the choice of wire feeder, and many customers have shouted injustice.

1.3 How to distinguish different grades from the advanced nature of WEDM?

All WEDM manufacturers have made a lot of publicity about their products. As users, especially those who don't know much about WEDM, it's difficult to tell the truth from the false. WEDM itself is a new concept, so most users are often "wise after the event".

The grade difference of WEDM machine tools should be distinguished mainly from the mechanical structure and control technology, not from the appearance or appearance of the machine tools. At present, most wire cutting machines on the market can only be regarded as simple wire cutting at best. This kind of machine tool adds the function of multiple cutting on the basis of fast wire cutting machine tool, and adds a guide rail which is extremely inconvenient for threading wire. In other respects, it has made no achievements in the structure or automatic control of machine tools.

Therefore, simple WEDM machine tools require high skills of operators. Operators should not only master the combination and matching of all high-frequency parameters with different materials, different thicknesses and different cutting times, but also often observe the operation of electrode wires, which requires high skills for operators. This is also the fundamental reason why most users are disappointed with WEDM.

Through the intelligence of the control system, the precision wire feeder realizes the intelligence of high frequency parameter control and feed tracking. Operators no longer need to master the selection and combination of high-frequency parameters. The process data provided by the system can provide corresponding cutting parameters, and users can modify the parameters according to their own material characteristics to form a corresponding user process database.

BSGXP control system is the most powerful processing technology database system in the market at present, which has the following six automatic technology functions:

① Automatically adjust the linear speed;

② Setting and adjusting the machining offset;

③ Intelligently set the number of tool repairs;

④ Automatic setting of high frequency parameter matching;

⑤ Automatic adjustment of feed tracking intelligence;

⑥ Short circuit judgment is automatically adjusted.

In this way, any beginner can quickly master the operation of the wire feeder.

Customers must know China silk loom thoroughly and carefully, shop around, listen more and see more, and never listen to it. Don't believe that high prices are always good. In the current silk cutting market, there are few manufacturers like Suzhou Gem Pavilion, which are transparent in price and publish all technical parameters. Not afraid of not knowing the goods, but afraid of shopping around. When buying medium-speed thread cutting, the actual cutting effect must be considered. Don't blindly believe the manufacturer's propaganda. The machine tool bought at sky-high price is not practical.

What are the four technical problems of WEDM in 1.4?

① Large-area stable cutting with low roughness.

(2) Ensure the absolute dimensional accuracy of multiple cutting processes.

(3) Consistency error in machining multiple identical parts.

④ Positioning accuracy of porous machining.

If these four key indicators are not effectively solved, it will not be a real wire cutting machine and will eventually be abandoned by the market.

Positec-M precision WEDM machine tool solves these technical problems well, and some technical parameters can be compared with WEDM machine tools.

What are the four obstacles to the operability of WEDM in 1.5?

(1) requires the operator to have very skilled winding and tightening skills;

(2) With experience, we should be able to pay attention to and eliminate the elastic change of electrode wire at any time;

(3) It is necessary to use a guide which is extremely inconvenient for threading, which is a great test for the operator's patience;

(4) The operator should master the combination and matching of more than a dozen process parameters such as various electrical parameters of different materials and thicknesses, machining allowance compensation, etc. Without considerable experience and time to verify, it is difficult to do so.

These problems have seriously hindered the popularization and application of WEDM.

Positec-M precision WEDM machine tool solves these technical problems.

1.6 How to judge the accuracy retention of WEDM?

To judge the quality of a real WEDM machine tool, we should not only look at the surface roughness of the workpiece, but also pay attention to the machining accuracy of the machine tool, and the machining accuracy should not only pay attention to the cutting accuracy, but also pay attention to the positioning accuracy of the machine tool. Because the actual service life of the machine tool far exceeds the warranty life, it is more important to judge the accuracy of the machine tool.

The accuracy retention rate of machine tools is mainly judged from the following two aspects:

The first is the mechanical structure of the machine tool itself, which is the foundation. No matter how beautiful the machine tool with unreasonable structure is, it is useless. The structure of machine tool determines the rigidity of machine tool, and the rigidity of machine tool determines the accuracy maintenance. At present, fully supported structures are considered as highly rigid structures. Taking machining centers as an example, all machining centers adopt fully supported structure because of the great cutting force, and WEDM also adopts fully supported structure in order to obtain high accuracy and stability of the whole stroke.

The biggest feature of the fully supported structure is that the movement of the workbench is always within the support range of the machine tool guide rail, which makes the machine tool have the smallest rigid deformation and is stable and reliable in the whole travel range.

The second is to know the technological level of machine tool production technology and the selection of key components, which is often difficult for users, but it can be understood from the aspects of enterprise reputation, user reputation and comprehensive strength of enterprises.

1.7 Can the grating ruler (electronic ruler) really improve the machining accuracy of WEDM?

The so-called fully closed-loop WEDM machine tool can obtain good machining accuracy, firstly, the structure of the machine tool, and secondly, the manufacturing quality of the machine tool itself. The application of grating ruler can only play a role on the basis of the above two points, because the detection position of grating ruler is not the machining position of machine tool, and there will always be errors in the straightness of movement when the workbench moves. Microscopically, as long as any two positions on the workbench do not overlap, their movements will be inconsistent when the workbench moves, and the greater their distance, the worse the consistency of their movements. However, the installation position of the grating ruler is often far away from the machining position, so there must be a large Abbe measurement error. In addition, the systematic error of all moving parts after assembly will inevitably lead to a great difference between the detection accuracy of the grating ruler and the actual accuracy of the machining position. Therefore, only a high-quality machine tool with reasonable structure can ensure the consistency of the two positions during the movement of the workbench. Facts have proved that the high precision of WEDM is not as simple as just installing a grating ruler. Therefore, customers should not be confused by the grating ruler when selecting the type, but should try to understand the structure and quality of the machine tool itself.

1.8 guide rail can really improve the accuracy?

As we all know, the gem guide is installed in the upper and lower thread guides of WEDM, which plays a key role in improving the accuracy. Because the wire feeding speed of WEDM is very slow and the wire feeding is made of copper with low hardness, the wear of electrode wire on the guide rail is very small. In addition, due to the small internal stress of copper, it is easy to straighten, so the electrode wire can easily pass through the guide manually (or automatically). However, the situation of WEDM is different. Because the electrode wire is molybdenum wire, its hardness and stress are much greater than that of copper wire. Observing molybdenum wire under microscope, there are a lot of "lumps" on the surface of molybdenum wire, which is tantamount to a "wire saw" for guiding molybdenum wire running at high speed. Therefore, compared with wire cut, the wear of the guide rail is very large, and it is difficult to overlap the small hole of the guide rail with the molybdenum wire between the upper and lower winches when installing the guide rail. This not only accelerates the wear of the guide rail, but also directly affects the spatial position of molybdenum wire during cutting. This is very fatal to the position accuracy of mold processing and the consistency accuracy of the same parts. In addition, due to the great internal stress of the molybdenum wire, the small hole of the guide can only be 0.0 1mm larger than the diameter of the molybdenum wire (otherwise there is no guiding effect), and both the guide and the molybdenum wire are full of working fluid, so it is difficult for the operator to pass the molybdenum wire through this small hole, which is a great test for the operator's patience. From the practical application, most customers finally gave up the application of guide rail, which shows that the application of guide rail is not the key to provide accuracy and smoothness for WEDM.

1.9 Why do some WEDM manufacturers demonstrate well, but they can't use it when they buy it back?

This is related to the current technical status of most wire feeders. Although it has the function of cutting many times, because of poor control technology, the operator is required to have a very skilled technical level, and it is difficult for the user's operator to reach this level, so the manufacturer demonstrates it very well. The demonstration is often a small-sized trial cut piece (which is also pretended by the wire cutting machine), but it cannot be used normally after being bought, so the real reason is the low technical level of the manufacturer.

How to correctly evaluate the cutting efficiency of WEDM?

Cutting efficiency is an important index to evaluate the performance of WEDM. For example, the maximum efficiency of WEDM can generally reach 300mm2/min. Due to different machining principles, WEDM and WEDM have different efficiency evaluations. For wire cutting, because the use of electrode wire is disposable, no matter how many wires are consumed, the processing is continuous, so his maximum efficiency is his normal working efficiency. However, for the intermediate WEDM, the situation is completely different. Because the electrode wire is reused, the wire consumption directly affects the length of continuous cutting, so it is necessary to add the condition of continuous cutting of more than 20000mm2 in the evaluation of online cutting efficiency (this is the cutting area of ordinary small and medium-sized molds). Therefore, the maximum cutting efficiency (referred to as maximum efficiency) and normal working cutting efficiency (referred to as working efficiency) are two completely different concepts for wire cutting machines with medium wire (including fast wire). The index that is really valuable to users is not maximum efficiency, but working efficiency. That is, it can continuously cut 20000mm2 continuous filaments, with the highest efficiency. It is conceivable that when you use the intermediate wire to process the mold, although the cutting efficiency reaches 300 mm2/min or even higher, the wire will still be broken in a short time. Can you still accept such efficiency?

1. 1 1 How to comprehensively evaluate the technical indicators of wire-walking?

Fierce market competition and the market's helplessness to China WEDM gave birth to many WEDM cutting manufacturers, which dazzled users. How to correctly evaluate the technical indicators of tightrope walking is the key to avoid being deceived.

Evaluation of a WEDM machine tool must start from two aspects. One is the technical indicators such as accuracy and roughness, and the other is operability, which is the concrete embodiment of the advanced nature of a machine tool. Without operability, it is meaningless to say technical indicators, and users must not only pay attention to accuracy and roughness. Because of this, it is difficult for most China WEDM machines to reach the targets advertised by the manufacturers after they reach the users. It can be seen that high indicators must be based on convenient operation. Only the machine tools with high degree of automation control can users easily get the benefits brought by high indexes.

Therefore, the evaluation of machine tools should first examine the operability.

At what stage has the wire feeder in 1. 12 developed?

At present, most WEDM machines are in the primary stage, at which the convenience of machine operation is very poor. These machine tools are in the initial stage or experimental stage, and the operation is difficult. The manufacturers exaggerate when promoting them, which brings endless confusion to customers.

1. 13 What functions should a truly practical middle thread cutting machine have?

The essence of WEDM is to cut the same surface many times with different parameter combinations. However, due to the different cutting materials and thicknesses, various parameters (such as voltage, current, pulse width, pulse interval, tracking frequency) need to be combined and matched during machining, which is difficult for ordinary customers to do comprehensively, and can only be done through numerical control technology and process database technology. As we all know, WEDM machine tools abroad can simplify the operation process, eliminate human factors as much as possible, and obtain good machining effect through parameter control.

1. 14 how to distinguish the operation convenience of wire feeder?

The expert database itself, the technical core of convenient operation, is a continuous optimization, continuous improvement and endless innovation process. This feature determines who develops it early. As time goes by, its convenience function will be more powerful and customers will be relaxed when applying it. Wire cutting is the best proof. The wire cutting machine in the 1950s is not as good as the fast-moving wire cutting machine now.

What is the core technology of 1. 15 WEDM?

The technical difficulty of WEDM is cutting with large area and low roughness, such as Ra = 1.0 ~ 1.2 um, and the machined surface is more than 25,000 m ㎡. If the high-frequency power supply, tracking speed and wire feeding can't be fully controlled automatically, it is difficult to realize. So as to realize full-automatic control of high-frequency electrical parameter control, feed tracking control and electrode wire dynamic control.

How to correctly understand the development of WEDM?

Medium-sized WEDM is the inevitable development direction of reciprocating WEDM in China, and it is an upgraded product of fast WEDM. Due to different market demands, WEDM will develop into three different market positions with different grades and prices, just like WEDM for wire shears. With the continuous innovation and development of WEDM technology, the high-grade WEDM machine tool will be equally divided with the entry-level WEDM machine tool and will gradually replace it.