There are several potential risks in using used machine tools:- **Technical performance issues**    - **Equipment wear and aging**: Used machine tools have been in operation for a certain period, resulting in inevitable wear and aging of components. This can lead to a decline in processing accuracy. For example, the guide rails of a lathe may wear out, affecting the straightness of the workpiece being processed. The spindle of a milling machine may have clearance, reducing the precision of milling operations. In severe cases, frequent breakdowns may occur, increasing maintenance costs and downtime, which in turn affects production efficiency.    - **Outdated technology**: With the rapid development of manufacturing technology, the functions and performance of new machine tools are constantly being upgraded. Used machine tools may have obsolete control systems, backward processing technology, and limited functionality. They may not be able to meet the requirements of modern high - precision, high - efficiency, and complex - shaped part processing. For example, an old - model machining center may lack advanced interpolation functions, making it difficult to machine complex curved surfaces.- **Lack of after - sales service**    - **Warranty limitations**: Most used machine tools are sold without a comprehensive warranty. Once a problem occurs, the buyer may have to bear the full cost of repair. Even if some used machine tools come with a limited warranty from the seller, the scope and duration of the warranty are often very limited.    - **Difficulty in obtaining spare parts**: As used machine tools are often older models, some manufacturers may have stopped producing relevant spare parts. This makes it difficult and expensive to source replacement parts. In some cases, it may be necessary to custom - make parts, which further increases the repair cost and time.- **Hidden defects and unknown history**    - **Previous misuse or abuse**: The previous user of the used machine tool may have used it improperly, such as overloading, operating without following the correct procedures, or lacking regular maintenance. These hidden problems may not be immediately apparent during the inspection before purchase but can cause serious failures and malfunctions during subsequent use.    - **Incomplete maintenance records**: Inaccurate, incomplete, or non - existent maintenance records make it difficult for the buyer to accurately assess the true condition of the machine tool. Some latent faults that have not been properly recorded or addressed may emerge after the machine is put into use, bringing unexpected troubles and costs to the user.

Using used machine tools offers several advantages, mainly in terms of cost - effectiveness, performance reliability, and diverse options. Here is a detailed breakdown:- **Cost - savings**: The most significant advantage is the lower price. Usually, the price of used machine tools is only a fraction of that of new ones. For example, a used lathe might cost 30% to 50% of the price of a new one. This significantly reduces the equipment procurement cost, allowing enterprises to save a large amount of capital, which can be used for other aspects of production and operation, improving the efficiency of capital utilization.- **Proven Performance**: Many used machine tools still have stable performance. If a machine tool has been well - maintained during its previous use, it can continue to perform reliably. Some high - quality machine tools can maintain good working conditions even after years of use. Moreover, since the machine has been in operation, potential issues have likely already surfaced and been addressed, making its performance more predictable and reliable in subsequent use.- **Immediate Availability**: In contrast to new machine tools, which often have a lead time for production and delivery, used machine tools can be put into use quickly. Once purchased, with some minor debugging and maintenance, they can be operational, reducing the waiting time for enterprises to start production and enabling them to respond more promptly to market demands.- **Wide Selection**: The market for used machine tools offers a rich variety of brands, models, and specifications. Whether an enterprise needs a common - use lathe, a precision milling machine, or a large - scale machining center, it is likely to find a suitable model in the used market. This wide range of options allows enterprises to select machine tools that precisely meet their production requirements, even if they have specific or unique processing needs.- **Lower Depreciation**: New machine tools experience significant depreciation in the first few years of use. In contrast, since used machine tools have already undergone some depreciation, their value tends to be more stable. For enterprises that may need to resell the equipment in the future, the loss from depreciation is relatively smaller.

Used machine tools refer to pre - owned machine tools that have been previously used in manufacturing or other industrial processes. Here is some relevant information about them: ### Market Situation- **Increasing Demand**: With the development of the manufacturing industry, many small and medium - sized enterprises are increasingly demanding used machine tools to reduce production costs and improve production efficiency. Due to their relatively low prices and acceptable performance, used machine tools have become a choice for many enterprises.- **Diverse Supply**: Used machine tools on the market come from a wide range of sources, including equipment phased out by enterprises during upgrades, equipment liquidated by bankrupt enterprises, and imported used machine tools from abroad. As a result, there is a rich variety of brands, models, and specifications of used machine tools available. ### Advantages- **Price - effective**: The price of used machine tools is usually only a fraction of that of new ones or even lower. For enterprises with limited funds, purchasing used machine tools can significantly reduce equipment procurement costs and improve the efficiency of capital utilization.- **Stable Performance**: Some used machine tools with a short service life and good maintenance still have relatively stable performance and can meet the production needs of enterprises. Moreover, after a period of use, some potential problems of the machine tools have been exposed and solved, making them more reliable in operation.- **Wide Selection**: There are numerous brands and models of used machine tools on the market. Enterprises can choose the ones that suit their production needs and budgets, including various types such as lathes, milling machines, grinders, and machining centers. ### Risks- **Equipment Aging**: Some used machine tools have been in use for a long time and may have problems such as aging and wear, which can affect processing accuracy and production efficiency, and increase maintenance costs and downtime.- **Outdated Technology**: With the continuous progress of science and technology, the technology of machine tools is also constantly being updated. Some used machine tools may have relatively backward technology and cannot meet the enterprise's requirements for high - precision and high - efficiency processing.- **Lack of After - sales Service**: Generally, used machine tools that have passed the warranty period are not covered by after - sales service. Although some used machine tools purchased through qualified and reliable second - hand companies may come with after - sales service, it is often more difficult to repair and maintain most used machine tools after purchase. ### Purchase Considerations- **Appearance Inspection**: Check whether there are obvious damages, deformations, rusts, etc. on the appearance of the machine tool. See if the paint is peeling off and whether the components are complete.- **Evaluate Service Life and Maintenance Conditions**: Find out the manufacturing date and service time of the machine tool. Check the maintenance records to understand its daily maintenance situation and judge the degree of wear and the remaining service life of the machine tool.- **Performance Testing**: Conduct a test - run to check whether all performance indicators of the machine tool are normal, such as spindle speed, feed rate, processing accuracy, etc. Observe whether there are any abnormal noises, vibrations, and other phenomena during the operation of the machine tool.- **CNC System Inspection**: For CNC machine tools, check whether the functions of the CNC system are normal, whether the program input, editing, and running are smooth, whether the display screen is clear, and whether the keys are sensitive. ### Transaction Channels- **Second - hand Equipment Markets**: There are some specialized second - hand equipment markets in various regions, which gather a large number of used machine tool suppliers and buyers. It is possible to on - site view and compare different machine tool equipment.- **Online Platforms**: Such as Wangyou Second - hand Equipment Network, Second - hand Machine Tool Network, 58 Tongcheng, etc. These online platforms provide rich information on used machine tools, which facilitates enterprises to search and filter, and directly contact the sellers.- **Auctions**: Some used machine tools are sold through auctions, such as those from bankrupt enterprise liquidations or enterprise equipment upgrades. It is possible to bid for good - quality machine tool equipment at a relatively low price at auctions.

Selection of tools suitable for Mazak QT250 CNC lathe machining, need to consider a number of factors, the following is the specific selection method:1, according to the processing material- **Steel parts**: processing of general hardness of steel parts, you can choose carbide tools, such as YW1, YW2 and other grades of inserts, with better wear resistance and cutting performance. For higher hardness steel parts, you can use cobalt-containing high-speed steel tools or coated carbide tools, coated tools can improve the hardness, wear resistance and lubricity of the tool, such as TiN coated tools.- **Cast iron parts**: when processing cast iron parts, tungsten and cobalt carbide tools can be used, such as YG6, YG8 and so on. These tools have better impact resistance and wear resistance, and can adapt to the intermittent cutting of cast iron materials.- **Non-ferrous metals**: Processing non-ferrous metals such as aluminum, copper, etc., diamond tools or PCD tools can be used, which have extremely high hardness and wear resistance, and can achieve high-precision and high-efficiency cutting, and obtain good surface quality. You can also use tungsten and cobalt carbide tools, cutting speed can be increased appropriately.2、According to the process requirements- ** Roughing **: roughing, in order to improve machining efficiency, should choose a large feed of the tool, such as indexable milling cutter, large size of the turning tool, etc.. The cutting edge of the tool should have strong impact resistance and wear resistance, and can choose carbide tools, and can use a larger tip arc radius to increase the strength of the tool.- **Finishing**: Finishing requires tools with high precision and surface quality to ensure the dimensional accuracy and surface roughness of the processed parts. For example, high-precision fine-tuning tools can be used for fine turning, and precision boring tools can be used for boring. Cutting edge of the tool should be sharp to reduce the cutting force and cutting heat, to avoid the production of chip tumors and burrs, can choose PCD tools, CBN tools or high-precision carbide tools.3、According to the performance of the machine tool- **RPM**: The maximum speed of Mazak QT250 CNC lathe is high, and the speed range of the tool should be considered when selecting the tool. For high-speed cutting, should choose a good dynamic balance, can adapt to the high speed of the tool, such as the use of HSK shank tool, has a better rigidity and accuracy retention, can adapt to the requirements of high-speed cutting.- **Power**: If the machine tool power is large, you can choose a large size, large feed tool, give full play to the power advantage of the machine tool, improve processing efficiency. For some complex machining, such as multi-axis linkage machining, you also need to consider the tool interference problem, select the appropriate tool shape and length, to avoid collision between the tool and the workpiece or fixture.4, according to the type of machining- **Turning**: external turning can choose different types of external turning tools, such as offset, sharp, arc knife, etc., according to the processing requirements to choose the appropriate insert material and type. Bore turning requires the selection of bore turning tools, according to the diameter, depth and accuracy requirements of the bore to select the size and accuracy level of the tool.- **Milling**: plane milling can choose end milling cutter, face milling cutter, etc.; contour milling can choose end milling cutter, ball end milling cutter, etc.. For some complex surface milling, you may need to use five-axis linkage milling machine and the corresponding tool, such as impeller processing can use a special impeller milling cutter.- **Drilling**: Select the appropriate drill bit according to the diameter, depth and accuracy requirements of the drill, such as ordinary twist drills, center drills, deep hole drills and so on. For high-precision drilling, reamers can also be selected for reaming processing to improve the dimensional accuracy and surface quality of the holes.5、 According to cost and efficiency- **Cost**: Under the premise of meeting the processing requirements, the cost of the tool should be considered. Generally speaking, the price of coated tools is relatively high, but long service life, the overall cost may be more cost-effective; and ordinary carbide tools are relatively low in price, suitable for some of the processing occasions that do not require high tool life.- **EFFICIENCY**: Selection of tools to consider its cutting efficiency, such as indexable tools due to the fact that they can continue to be used by replacing the inserts, reducing the tool replacement time and improving the processing efficiency. Some new tool materials and tool structure, such as high-efficiency milling cutters, new drills, etc., can increase the cutting speed and feed, thus shortening the processing time and improving productivity.

Mazak QT250 CNC lathe can use a variety of types of tools, tool models and specifications will vary depending on the processing needs and workpiece materials. The following is to introduce you to the common types of cutting tools and the corresponding model specifications example:1、Outside turning tool - **Use**: Mainly used for turning external cylindrical surfaces, conical surfaces, etc. - **Model example**:    - **DNMG150608**: “DNMG” is the insert model code, “15” that the insert diameter of the inner cutting circle is 15.875mm, “06” indicates that the thickness of the blade is 6.35mm, “08” indicates that the radius of the tip of the blade is 0.8mm.    - **CNMG120404**: “CNMG” is the code, “12” means that the diameter of the inner cutting circle of the blade is 12.7mm, “04” represents the thickness of the blade 4.76mm, “04” that the tip of the arc radius 0.4mm.2、Bore turning tool - **Use**: Used for processing internal holes, such as blind holes, through holes, etc.. - **Examples of models**:    - **CCMT09T304**: “CCMT” is the blade model, “09” that the blade inner cutting circle diameter 9.525mm, “T3” that the blade Thickness of 3.97mm, “04” that the tip of the arc radius of 0.4mm.    - **TCMT16T304**: “TCMT” for the code, “16” on behalf of the blade diameter of the inner cutting circle 16.51mm, “T3” that the blade thickness of 3.97mm, “04” that the tip of the arc radius 0.4mm.3, cut off the knife - **Use**: Used to cut off the workpiece or cut grooves in the workpiece. - **Example of model number**:    - **VCMT090204**: “VCMT” is the blade model, “09” that the blade inner cutting circle diameter 9.525mm, “02” that the blade Thickness of 2.38mm, “04” that the tip of the arc radius 0.4mm.    - Cutting knife width specifications, common 2mm, 3mm, 4mm, etc., according to the diameter of the workpiece and cut off the requirements of the choice.4、Thread Turning Tools - **Use**: Used for processing a variety of threads, such as triangular threads, trapezoidal threads, etc.. - **Model Example**:    - **TNGP160304**: “TNGP” is the blade model, “16” that the blade internal cutting circle diameter 16.51mm, “03” that the blade Thickness of the insert is 3.18mm, and “04” means that the radius of the tip of the insert is 0.4mm.    - The tooth angle of the thread turning tool is 60° (for ordinary triangular threads), 55° (for inch threads), and so on.5、Drill - **Use**: Used for drilling holes in workpieces. - **Examples of specifications**: There are abundant specifications of drill diameters, ranging from several millimeters to tens of millimeters, such as φ3mm, φ5mm, φ10mm, etc. The length of drill bits also varies. The length of the drill bit also has different specifications, common short drill bit, long drill bit, etc., in order to adapt to the different depth of the drilling needs.6、Reamer - **Use**: Used for finishing drilled holes to improve the dimensional accuracy and surface quality of the holes. - **Specification example**: The reamer diameter usually matches the size of the hole to be processed, such as φ6H7, φ8H7, etc., where “H7” indicates the tolerance level of the hole. The number of edges of the reamer usually has 4 edges, 6 edges and so on. 

The wearing parts of Mazak QT250 CNC lathe mainly include the following categories:- **Tools**: CNC lathe in the process of processing, the tool will constantly contact with the workpiece and cutting, so tool wear is inevitable. For example, the cutting edge of the lathe tool will gradually wear out, boring tools, drills and other tools in the use of the process will also be affected by wear and tear of machining accuracy and efficiency, and need to be replaced periodically.- **Guide guards**: such as machine tool guide guards, which are used to prevent chips, coolant, etc. from entering the guide, to protect the accuracy and life of the guide. However, in long-term use, the guard plate may be damaged or deformed due to collision, friction and other reasons, and needs to be replaced in time to ensure its protective effect.- **Chip removal device parts**: The scraper, chain and other parts of the chip removal machine will wear out due to friction with the chips and frequent movement during long-term operation. If the scraper wears seriously, it may lead to poor chip discharge; if the chain wears, it may be loose, broken and other problems, affecting the normal work of the chip removal device.- **Components of the lubrication system**: The oil pump, oil nozzle, oil pipe and other components in the lubrication system are prone to malfunction or blockage. The oil pump may be worn out after a long period of work, resulting in insufficient oil supply pressure; the oil nozzle and oil pipe may be clogged with impurities, affecting the normal supply of lubricant, thus affecting the lubrication effect of various parts of the machine tool.- **Some components of the electrical system**: such as relays, contactors, fuses, etc.. Relays and contactors in the process of frequent opening and closing of the circuit, its contacts are prone to wear and abrasion, resulting in poor contact or can not be properly suction, disconnection; fuse in the circuit overload, short circuit and other faults will be melted, need to be replaced in a timely manner.- **Cooling system components**: cooling pumps in long-term operation, its impeller, seals, etc. may wear out, resulting in cooling pump flow and pressure drop, affecting the cooling effect. Cooling pipes may also be clogged by impurities, scale, etc. in the coolant and need to be cleaned or replaced regularly.- **Drive system parts**: such as belts, gears, bearings, etc. Belts will slacken and wear after a long time of use, affecting transmission accuracy; gears in the transmission process, the tooth surface will be due to wear, fatigue, etc., tooth shape changes, affecting the transmission efficiency and accuracy; bearings are the key components to support the rotating parts, long-term use may be worn, increased clearance and other problems, resulting in a decline in the accuracy of the spindle or other rotating parts.

When buying used Mazak QT250 CNC lathe, you need to consider the overall condition of the machine, performance performance, technical data and other aspects to ensure that you buy the equipment that meets your needs and is reliable in quality. The following are specific things to pay attention to:1. **Overall condition of the equipment** **Overall condition of the equipment** **Overall condition of the equipment    - **Useful life and appearance **: Check the production date and use of the equipment, in general, the use of a shorter life of the equipment is relatively less wear and tear. At the same time, observe the appearance of the machine tool there is no obvious bumps, scratches, paint, etc., if there are more such problems, may reflect the lack of good maintenance of the equipment in the use of the process, or have experienced a more severe use of the environment.    - ** mechanical parts wear **: focus on checking the spindle, guide, screw and other key mechanical parts of the degree of wear. Can be manually operated by the machine tool axes movement, feel whether there is jamming, abnormal resistance or excessive gap phenomenon. For the spindle, you can check whether its radial runout and axial runout are within the allowable range, which directly affects the machining accuracy. Wear and tear of the guide rail and screw will lead to a decrease in motion accuracy, affecting the machining dimensional accuracy and surface quality of the parts.    - **Electrical system**: Check whether there are signs of aging, damage, overheating and discoloration of electrical components in the electrical cabinet, and whether there are problems such as broken wires, aging and short circuits. Check whether the system parameters are normal and whether there are any alarm messages. If there are problems with the electrical system, it may lead to unstable operation and frequent failures of the machine tool, and even affect the machining accuracy and safety.    - **Lubrication and cooling system**: Check whether the lubrication system is working properly, whether the lubrication points can be well lubricated, and whether the oil quality and quantity of lubricant meet the requirements. For the cooling system, check whether the cooling pump can work normally, and whether there is any blockage and leakage of the coolant pipeline. The lubrication and cooling system is vital to the normal operation and life of the machine tool, and if there are problems with the system, it may lead to overheating and increased wear of the machine parts.2. **Machine tool performance test**    - **Precision testing**: Use laser interferometer, ballbar and other professional testing equipment to test the positioning accuracy, repeat positioning accuracy, perpendicularity, parallelism and other precision indicators of the machine tool. You can also check whether the machining accuracy of the machine tool meets the requirements by machining some standard test pieces, such as cylindrical, plane, thread, and so on.    - **Functional test**: Comprehensive test of the various functions of the machine tool, including spindle forward and reverse, high and low-speed operation, turret tool change action, tailstock expansion and contraction, as well as a variety of automatic cycle function. Check whether each function can be realized normally, whether the action is accurate and smooth, and whether there is any abnormal noise or jamming phenomenon.    - **Load test**: Within the permitted range of the machine tool, run the test under different load conditions. It can be used to simulate the load conditions in the actual machining process, observe whether the running status of the machine tool, motor current, voltage and other parameters are stable, and judge the performance of the machine tool under different loads.3. **Equipment history**    - **Use records**: Learn from the seller about the frequency of use of the equipment, the main types of parts processed, routine maintenance, etc.. If the equipment is used frequently and the parts processed are of high strength and high precision requirements, the wear and tear of the equipment may be relatively large. And good maintenance records can to some extent reflect the potential better condition of the equipment.    - **Maintenance records**: check the maintenance records of the equipment, to understand whether there has been a major failure, as well as the cause of the failure and repair. Especially for the key components of the maintenance records to focus on, such as the spindle, guide rail and other maintenance, which may affect the performance and reliability of the equipment.4. **Random accessories and technical data**    - **Random accessories**: Confirm whether the equipment's random accessories are complete, such as tools, chucks, tailstock, center stand, etc.. The completeness of these accessories is very important for subsequent machining production. If key accessories are missing, it may increase the purchase cost and time cost.    - **Technical information**: the seller is required to provide the technical information of the equipment, such as machine tool manuals, electrical schematics, PLC programs, etc.. This information is very important for the operation, commissioning, maintenance and repair of the equipment, and the lack of information may cause many inconveniences to the subsequent use.5. **Price assessment**    - **Market Research**: Before buying, understand the price quotations of used Mazak QT250 CNC lathes of the same model and age in the market, which can be carried out by consulting used equipment dealers, checking relevant industry websites or forums, and asking experienced peers for advice.    - **Comprehensive Assessment Pricing**: Based on the actual condition of the equipment, performance test results, accessories and completeness of the information and other factors, comprehensively assess the value of the equipment to determine a reasonable purchase price, to avoid the information asymmetry that leads to the price is too high or too low.6. **Transaction contract**    - **Clear terms**: Before signing the transaction contract, carefully read the terms of the contract to ensure that the contract specifies the model, specifications, configuration, price, delivery time, payment method, after-sales service and other important information of the equipment. There should also be a clear agreement on the quality assurance terms of the equipment, warranty period, liability for breach of contract, etc., in order to protect their legitimate rights and interests. Buying used Mazak QT250 CNC lathe needs to be careful and meticulous, as comprehensive as possible to understand all aspects of the equipment, if necessary, can hire professional technicians or third-party testing organizations to assist in the assessment, in order to ensure that the purchase of cost-effective and reliable quality equipment.

Mazak QT250 is a CNC lathe produced by Yamazaki Mazak, and will be introduced in detail from the following dimensions: machining capacity, structural design, control system, degree of automation and so on:1、Machining capability    - **Rotary diameter and processing diameter**: the maximum rotary diameter of up to 23.6 inches, the maximum processing diameter of 15.7 inches, able to process a certain size range of various rotary body parts.    - **Machining Length**: The maximum machining length is 19.7 inches, which can meet the machining requirements of some longer shaft parts.    - **Spindle Parameters**: Equipped with a 25hp spindle motor, the spindle speed ranges from 40-4000rpm, which can be flexibly adjusted according to different machining materials and process requirements to achieve the best machining results. In addition, the spindle bore diameter is 2.44 inches, and the maximum bar passing diameter is 2 inches, which is convenient for processing bar type parts.2、Structural design    - **Bed**: Adopting high-precision bed structure with good rigidity and stability, it can effectively reduce vibration and deformation during machining to ensure machining accuracy.    - **Turret**: Equipped with a 12-station turret, it can be installed with a variety of different types of tools, such as turning tools, boring tools, drills, etc., which realizes the one-time completion of a variety of machining processes, reduces the time of tool change, and improves the machining efficiency.    - **Tailstock**: With programmable tailstock, tailstock sleeve taper is MT#4, tailstock body stroke is 18.1 inches, tailstock sleeve stroke is 5.1 inches, which can be used to support longer workpieces and improve stability during machining.3、Control System    - **MAZATROL Fusion 640T system**: Mazak QT250 is equipped with the MAZATROL Fusion 640T CNC system, which has a dialog programming function and is easy and convenient to operate, so that even operators without extensive programming experience can get started quickly. It also supports EIA/ISO standard code programming, which can meet the programming needs of different users.- **Automation degree**    - **Automatic chip removal device**: It is equipped with automatic chip removal device as standard, such as scraper chip removal machine or chain plate chip removal machine, which can timely remove the chips generated in the process of machining out of the machine tool and keep the working area clean, which is conducive to improving the machining efficiency and quality, and reduces the workload of manually cleaning the chips.    - **Tool detection function**: The machine tool is equipped with tool detection devices, such as Tool Eye, which can automatically detect the wear and breakage of the tool and remind the operator to replace or adjust the tool in time to ensure the machining accuracy and tool life.4、Other Features    - **Rapid feed**: X-axis rapid feed speed is 1200 ipm, Z-axis rapid feed speed is 1300 ipm, which can quickly locate the tool, reduce non-processing time, and improve processing efficiency.    - **Protection device**: It is equipped with perfect protection devices, such as machine guard, which can effectively prevent chips and coolant from splashing and protect the safety of operators and the neat appearance of the machine tool.

Here are some ways to determine if a slow-feeding machine needs to be repaired: ### In terms of machining accuracy- **Dimensional deviation**: If the size of the processed workpiece is consistently out of tolerance compared to the design size, for example, when processing a batch of mold parts, the dimensional accuracy is required to be ±0.01mm, but the actual size deviation of the processed parts exceeds this range and cannot be improved by adjusting the machining parameters, it is possible that the mechanical structure of the equipment, the control system, or the discharging system has a This may be a problem with the mechanical structure of the equipment, the control system or the discharge system, and maintenance is required.- **Decline in shape accuracy**: When the shape of the processed workpiece is obviously not in line with the requirements of the situation, such as cylindricity, flatness, straightness and other shape accuracy indicators deteriorate. For example, the cylindricity error of the processed cylindrical parts increases from the original 0.002mm to more than 0.01mm, or there is a wavy undulation after the plane processing, which is most likely caused by the wear of the guide rail, the reduction of the precision of the silk rod, the uneven discharge, etc., and needs to be repaired.- **Surface roughness deterioration**: Under normal circumstances, slow walking wire processing can achieve a better surface roughness, such as Ra value below 0.8μm. If the surface roughness deteriorates significantly during processing, and there are obvious lines, pockmarks, scratches, etc. on the surface, and it is not due to changes in the electrode wire, processing parameters, or workpiece materials, the discharge circuit, working fluid system, or mechanical transmission components may be faulty, and the equipment needs to be inspected and repaired. ### Electrode wire operation aspects- **Automatic Threading Failure**: If the success rate of automatic threading decreases significantly, e.g., if the success rate of automatic threading was originally above 95%, but now threading fails frequently, or if the threading time increases significantly beyond the normal range (e.g., from an average of 15 seconds to more than 1 minute), it may be a result of the wear of the mechanical parts of the automatic threading mechanism, a faulty sensor, or a problem with the electrical control system that Repair is required.- **Electrode wire tension abnormality**: When the electrode wire tension is unstable and fluctuates significantly during processing, or the tension display value is out of the normal range, it will cause the electrode wire to jitter and affect the processing accuracy. This may be a failure of the motor, sensor, controller and other components of the tension control system, which needs to be repaired.- **Frequent electrode wire breakage**: under normal processing parameters and material conditions, the electrode wire breaks frequently, e.g. originally the number of wire breakage was not more than 2 - 3 times in a day, but now the wire breaks every time a few workpieces are processed, which may be caused by the quality of electrode wire, abnormal discharge parameters, insufficient supply of working fluid or poor chip removal, etc., and the relevant systems of the equipment need to be inspected and repaired. ### Mechanical movement- **Abnormal table movement**: When the table has obvious jamming, jittering, crawling phenomenon in the process of moving, or the moving speed is unstable, for example, the speed appears to be fast and slow when the uniform speed is set, which may be caused by the wear of guide rail, the decline in precision of silk rod, motor failure or loose transmission parts, etc., and it is necessary to carry out repairs on the mechanical movement system.- ** Inaccurate positioning of the axes **: equipment in the positioning operation, the axes can not accurately reach the set position, there is a large positioning error, more than the range allowed by the equipment (such as positioning accuracy requirements for ± 0.005mm, but the actual error reaches more than 0.01mm), which may be a failure of the encoder, the transmission system error accumulation or control system positioning algorithm problems, need to carry out maintenance. ### Control system aspects- **Error in program execution**: If there is an error in the execution of the machining program by the equipment, for example, it cannot recognize the program instruction correctly, the machining path is deviated, and it cannot be machined according to the set parameters, etc., this may be a CNC system software failure, program transmission error, or a controller hardware failure, which needs to be inspected and repaired on the control system.- **Frequent system alarms**: The control system of the equipment frequently sends out alarm signals, and the alarm information shows that it is related to the hardware or software failure of the equipment, such as motor overload alarms, abnormal discharge alarms, high temperature alarms, etc., which indicates that there are problems with the equipment, and it needs to be repaired accordingly based on the alarm information. ### Working fluid system aspects- **Working fluid level abnormality**: The working fluid level shows abnormal fluctuation, such as the level drops too fast, or the level sensor malfunctions cause the equipment can't recognize the level height correctly, which may be caused by the working fluid tank leakage, pipeline rupture, or the level sensor is damaged, etc., and needs to be repaired.- **The working fluid temperature is too high**: under normal processing conditions, the working fluid temperature is too high, exceeding the temperature range specified by the equipment (e.g., more than 60 ℃), which will affect the performance of the working fluid and the processing quality, it may be the working fluid cooling system failure, such as damage to the cooling pump, radiator clogging, etc., and need to be repaired.- **Serious contamination of the working fluid**: the working fluid becomes turbid, has a strange odor, or it contains a large number of metal shavings, impurities, etc. This will affect the insulating performance and chip removal effect of the working fluid, which may be caused by the failure of the filtration system or a long period of time without replacing the working fluid, and the working fluid system needs to be repaired or maintained. ### Electrical system- **Equipment fails to start or stops suddenly**: When the equipment fails to start normally after the start button is pressed, or stops suddenly during the machining process, and there is no obvious external reason (e.g., power outage), this may be caused by power supply failure, contactor failure, motor failure, or control system failure, etc., and the electrical system needs to be comprehensively inspected and maintained.- **Abnormal heat or smoke in electrical components**: In the process of equipment operation, found that some components in the electrical control cabinet (such as transformers, contactors, drives, etc.) appeared abnormal heat, or even smoke, which indicates that these components may have been damaged or short-circuit and other malfunctions, the need for immediate shutdown and maintenance.

Evaluating the performance and quality of a used jogging wire requires a comprehensive consideration of several aspects, and here are some specific ways to do so: ### Machining accuracy- **Direct Measurement Method**: Use professional gauges to measure the accuracy of workpieces processed by the slow-feeding wire equipment. For example, use calipers to measure the dimensional accuracy of the processed parts, including the length, width, height and other dimensions, to see if they meet the nominal machining accuracy range of the equipment. For shape accuracy, you can use a micrometer to measure cylindricity, flatness and other indicators. For example, machining a cylinder with a diameter of 10mm, the cylindricity deviation should be within the accuracy range specified by the equipment, such as ±0.005mm.- **Test Piece Processing Evaluation**: Evaluate the accuracy of the equipment by processing standard test pieces. For example, process a specimen with different shape characteristics (e.g. square, round, skew, etc.) and observe its dimensional accuracy, shape accuracy and surface roughness. For high-precision slow-feeding equipment, the dimensional accuracy of the machined specimen can reach ±0.001mm, and the surface roughness Ra can reach below 0.8μm. ### Cutting speed- **Practical test**: Compare the cutting speed of the equipment under the same processing conditions (e.g. using the same electrode wire, the same processing parameters, the same workpiece material, etc.). You can choose a standard size and thickness of the workpiece, such as a piece of mold steel with a thickness of 50mm and an edge length of 200mm, and record the time required for the equipment to finish cutting the workpiece. Equipment that cuts faster can complete the processing task in a shorter period of time, which is critical to improving productivity.- **Technical Parameters Comparison**: Check the equipment's technical parameters manual to understand its nominal cutting speed range. However, it should be noted that the actual cutting speed may be affected by a variety of factors such as equipment aging, wear and tear, and processing conditions, so the technical parameters are only used as a reference. ### Electrode wire operation system- **Automatic Threading Function Test**: Perform automatic threading operation several times to check the success rate and time required for threading. For a good performance of slow walking equipment, the success rate of automatic threading should be above 95%, and the threading time is shorter, usually around 10 - 30 seconds. Observe whether the threading process is smooth, there is no jamming, broken wire and other conditions.- **Electrode wire tension control check**: Check whether the electrode wire tension control system is working properly. Stable tension is very important to ensure processing accuracy and surface quality. You can check whether the tension of the electrode wire is within the specified range through the tension display device of the equipment or with a tensiometer, and whether the tension can be kept stable during the processing. ### Mechanical structure- **Appearance Inspection**: Look at the overall appearance of the equipment and check whether there are obvious traces of collision, deformation, paint loss, etc. on the body of the machine. These surface damages may imply that there are also problems with the internal structure of the equipment, or that it has been subjected to improper use or transportation.- **Guide rail and screw check**: Check the wear and tear of the equipment's guide rails and screws. Slight wear may affect machining accuracy, while severe wear may cause the equipment to move unevenly, lose accuracy or even fail to work properly. You can move the table manually to feel the smoothness of the movement, or use a tool such as a plug ruler to measure the gap between the guide rail and the silk rod. ### Control system- **Functional Integrity Test**: Check whether the functions of the CNC system are normal, such as program input and output, coordinate display, machining parameter setting, automatic compensation and other functions. Try to input different types of machining programs and observe whether the equipment is able to perform the operation correctly and automatically compensate according to the set parameters during the machining process to ensure the machining accuracy.- **System stability assessment**: During the operation of the equipment, observe whether the CNC system will crash, report errors, program interruptions and other abnormalities. A stable control system is one of the key factors to ensure the stable operation of the equipment for a long time. ### Working fluid system- **Cleanliness check**: See whether the inside of the working fluid tank is clean, with no impurities, sediments and oil, etc.. The cleanliness of the working fluid will directly affect the processing effect and equipment life. If the working fluid tank is dirty, it may lead to contamination of the working fluid, which in turn affects the discharge performance of the electrode wire and machining accuracy.- **Working fluid circulation and filtration check**: Check the working condition of the working fluid pump, including whether the pump pressure and flow rate are normal, and whether the filter is clogged. Problems with the working fluid pump and filter will affect the circulation and filtration effect of the working fluid, resulting in poor chip removal and high temperature in the machining area, thus affecting the machining quality. ### Electrical system- **Electrical component inspection**: Open the electrical control cabinet of the equipment and check the appearance of the electrical components for signs of burning, discoloration, corrosion, etc., which may indicate component malfunction or aging problems. At the same time, check whether the connection of the wire is firm, there is no damage, aging and so on.- **Insulation Performance Test**: Use an insulation resistance tester to check the electrical insulation performance of the equipment to ensure that there is no risk of leakage. Good insulation performance is one of the important conditions to ensure the safe operation of the equipment.

The following are some of the factors that can affect the price of a jogging machine: ### Brand factors- **Brand awareness**: such as Fanuc, Shadick, Charmilles and other international brands, by virtue of its long-accumulated good reputation, advanced technology and high-quality product quality, has a high brand value in the market, and the price of its equipment tends to be on the high side.- **Brand market positioning**: high-end brands usually focus on technological research and innovation, is committed to providing customers with high-precision, high-performance, high-stability slow-wire equipment to meet the high quality and efficiency of processing requirements of the user needs, so the price positioning is also higher; and low-end brands may be more focused on the price competition to attract the more price-sensitive, relatively low-processing requirements of the customer base. ### Technical parameters- **Machining Accuracy**: Machining accuracy is one of the key indicators of the slow-feeding equipment, the higher the accuracy of the equipment, such as the ability to achieve smaller dimensional tolerances and higher surface roughness requirements, its price is usually higher. For example, some used in aerospace, precision mold manufacturing and other areas of ultra-high precision slow walking wire equipment, the price is often much higher than the ordinary precision equipment.- ** cutting speed **: cutting speed of the slow walking wire equipment can improve productivity and reduce processing costs, but this type of equipment is usually in the technical development, motor performance, control systems and other aspects of higher requirements, so the price will be raised accordingly.- ** processing size range **: equipment table size, stroke and the maximum size of the workpiece can be processed and other parameters determine the range of parts it can process. The larger the processing size range of the slow-feeding equipment, the higher the price, because it requires a larger body structure, a stronger drive system and a more stable control system to ensure processing accuracy and stability.- **Automation**: A high degree of automation of the slow walking equipment, such as automatic threading, automatic unloading, automatic compensation and other functions, can reduce manual intervention, improve production efficiency and processing quality, but also increase the manufacturing cost and price of the equipment. ### Equipment configuration- **Core component quality**: The quality of the core components of the host, control system, motor, guide rail, silk rod and other core components of the slow-feeding equipment directly affects the performance and service life of the equipment. The use of high-quality imported components or well-known brands of domestic components, will increase the cost of equipment, the price will increase accordingly.- **Accessories equipped with **: equipment equipped with accessories will also have an impact on the price, such as cooling system, chip removal system, electrode wire tension control system, filtration system. Full-featured, high-performance accessories can improve the overall performance of the equipment and processing quality, but will also increase the total price of the equipment. ### Equipment new and old degree- **Brand new equipment**: The price of brand-new slow-feeding equipment is relatively high because it includes the equipment's research and development costs, manufacturing costs, sales costs and a reasonable profit margin. At the same time, brand new equipment also enjoys complete after-sales service and warranty period, which is also part of its price.- **Used equipment **: the price of used slow-feeding equipment is relatively low, its price is mainly affected by the equipment's service life, frequency of use, maintenance and color of the equipment and other factors. The price is mainly affected by the use of the equipment, the frequency of use, maintenance and equipment and other factors. The use of shorter, well-maintained, newer used equipment prices will be relatively high, while the use of longer, equipment wear and tear of the second-hand equipment prices will be lower. ### Market demand and supply- **Market Demand**: When the market demand for slow-feeding equipment is strong, the supply exceeds the demand, manufacturers in order to obtain higher profits, will be appropriate to increase the price of the equipment; on the contrary, when the market demand is weak, the supply exceeds the demand, manufacturers in order to promote the sale of equipment, will reduce the price to attract customers.- **Market Competition**: A competitive market environment will prompt manufacturers to continuously improve product quality, reduce costs, and through pricing strategies to compete for market share. In a competitive market, consumers have more choices, it is easier to find cost-effective equipment, which has a certain inhibition on the price. ### After-sales service- **Service quality**: Quality after-sales service is vital to the normal operation and long-term use of slow-feeding equipment. Provide perfect after-sales service, such as timely technical support, fast maintenance response, adequate supply of spare parts, etc., manufacturers need to invest a lot of manpower, material and financial resources, so after-sales service quality of the brand, the price of its equipment will be relatively high.- **Service content**: different brands and manufacturers to provide after-sales service content may vary, some manufacturers may provide a longer warranty period, free training services, regular equipment maintenance, etc., these additional services will also increase the value and price of the equipment.    

Here are some recommended brands and models of slow-wire equipment:### Fanuc- **α-C400iB**: Table travel is 400mm×300mm, Z-axis travel is 255mm, workpiece size can be processed 730mm×630mm×250mm, using wire diameter 0.1-0.3mm, suitable for processing small and medium-sized precision parts, the equipment has high precision, automatic threading function is powerful, it can complete the automatic threading of 0.10 fine wire in 10 seconds, and it has good processing stability and can effectively guarantee the processing precision and surface quality. The machine has high precision and powerful automatic threading function, which can finish 0.10 fine wire threading automatically within 10 seconds.- **α-C600iB**: Stroke 600mm x 400mm, Z-axis stroke 310mm, workpiece size 1050mm x 820mm x 300mm, load capacity up to 1000kg, suitable for medium-sized molds and parts machining, high cutting efficiency to meet the needs of mass production, and its high-precision positioning and repetitive positioning system, which ensures the consistency of the machining dimensions. .- **α-C800iB**: Table travel 800mm×600mm, Z-axis travel 310mm, workpiece size up to 1250mm×1020mm×300mm, mainly used for large molds and large parts machining, with strong cutting capacity and stability, can adapt to complex shapes and high-precision requirements of the machining task.### West- **M35HP**: the movement of each axis is 350mm×300mm×230mm, the maximum workpiece size is 700mm×630mm×220mm, the maximum workpiece weight is 350kg, the diameter of the wire electrode is 0.07-0.3mm, it is suitable for small precision parts machining, it has the characteristics of high precision and high efficiency, and its pitch machining accuracy can reach ±1um, it can It has high precision and high efficiency, and its pitch machining precision can reach ±1um, which can meet the production of parts with extremely high requirements for machining precision.- **M50B**: table stroke 500mm x 350mm, maximum cutting thickness 300mm, surface roughness 0.2um, electrode wire diameter range 0.1-0.3mm, maximum load-bearing capacity of 800Kg, taper ± 10 ° / plate thickness of 300mm, can be processed for larger sizes and weights of the parts, while maintaining a high degree of machining accuracy and surface quality, and can adapt to the needs of diversified precision machining. It can meet the diversified demands of precision machining.### Sardick- **AQ325L**: with high cutting accuracy and surface quality, it is suitable for processing small and medium-sized precision molds and parts, with good stability and long time stable operation, which can effectively reduce the production interruption caused by equipment failure and improve the production efficiency.- **AQ400LS**: excellent processing accuracy and stability, can achieve high precision cutting processing, suitable for the processing of parts with strict requirements for dimensional accuracy and surface roughness, such as precision molds, aerospace parts and so on.- **ALN400**: balanced performance in cutting efficiency and precision, can meet the general demand for precision parts processing, has a good cost performance, suitable for small and medium-sized enterprises and processing workshop selection.### Charmilles- **CUT P 350 Pro**: The standard configuration of wire guide nozzle diameter is 0.10-0.30mm, the maximum cutting taper is 30°/100mm, the maximum moving speed of X and Y axes is 3m/min, and the threadable height is 250mm, which is suitable for machining small precision parts with high precision and high efficiency, and its advanced electronic control system can provide higher machining precision and stability.- **CUT P 550 Pro**: similar performance to CUT P 350 Pro, but the processing size range is larger, can meet the processing needs of medium-sized parts, with higher cutting accuracy and surface quality, can effectively improve processing efficiency and product quality.- **CUT P 800 Pro**: can process parts of larger sizes, the maximum cutting taper and threading height and other parameters are further improved, suitable for large molds and parts processing, its stable cutting performance and high-precision machining capabilities to ensure that the processing of large parts precision and quality.### Mitsubishi- **FA20S**: suitable for processing small precision parts, with high processing accuracy and stability, high success rate of automatic threading, easy to operate, can effectively improve processing efficiency and reduce labor costs, suitable for small and medium-sized enterprises and processing workshops.- **MV1200S**: Adopting sleeve linear motor drive and Opt Drive System, it improves machining precision and response speed, realizes high speed machining of micro-fine surfaces, greatly improves the success rate of automatic threading of electrode wires, and extends the corresponding range of bending rate from 3% to 10%, and greatly improves the success rate of threading of broken wires of thick plates, which is suitable for machining of parts with high requirements for machining precision and surface quality. This makes the machine suitable for processing parts with high demands for machining accuracy and surface quality.- **DWC-200HA**: With excellent performance in precision and efficiency, it can meet the needs of medium and large-sized molds and parts processing, and its advanced drive system and control system can ensure the stability and precision of the processing process and improve productivity.### Precision Presentation- **V50 water jet type**: large workpiece size 950mm x 650mm x 255mm, XY-axis travel 500mm x 300mm, UV-axis travel 120mm x 120mm, Z-axis travel 260mm, using wire diameter 0.15-0.3mm, adopting stabilized arc-inducing voltage circuit and electrolysis-free discharging power supply system, which can maintain cutting stability and increase speed, and at the same time The RTS discharge circuit can effectively monitor the discharge state, reduce the phenomenon of broken wires, and improve the processing efficiency and precision.