You can evaluate whether the price of second-hand punching machines is reasonable from the following aspects: 1. Brand and model factors Brand value: Second hand punching machines from well-known brands are relatively expensive. For example, brands such as Yangli and Xieyi have a high reputation in the field of punching machines, and their equipment performs well in terms of quality, accuracy, and stability. Under the same tonnage and service life, the price of second-hand punching machines from these brands will be about 10% -30% higher than that of small brands. Because branded products have more assurance in design, manufacturing processes, and material selection, the durability and performance of equipment are more trustworthy. Model differences: Different models of punching machines have different functions and performance, and their prices may also vary. For example, CNC punching machines are generally more expensive than ordinary mechanical punching machines due to their higher degree of automation and precision. Even for second-hand CNC punching machines, their price may be 1.5-2 times that of ordinary punching machines of the same tonnage. In addition, some models with special functions (such as high-speed stamping, deep throat punching, etc.) may also have different prices. For example, deep throat punch presses can process longer sized workpieces, which may be about 20% more expensive than regular punch presses. 2. Equipment performance indicators Accuracy status: The accuracy of the punching machine has a significant impact on the price. If the slider of a second-hand punch press has high perpendicularity to the worktable, good worktable flatness, and the stroke accuracy can reach a high standard (such as slider perpendicularity error within ± 0.05mm/300mm stroke, worktable flatness error less than 0.05mm), its price will be much higher than that of a punch press with poor accuracy. High precision punching machines can produce high-quality stamped parts, which are more valuable in the field of precision stamping. Generally speaking, the price of second-hand punch presses with good accuracy will be 20% -50% higher than those of the same model with poor accuracy. Stamping tonnage and stroke: Stamping tonnage is a key indicator of punching machines. The larger the tonnage, the higher the price usually. For example, the price of a 160 ton second-hand punch press will be much higher than that of a 25 ton punch press. Meanwhile, the stroke of the slider is also one of the factors affecting the price. Punching machines with longer strokes can process larger workpieces at relatively higher prices. All other conditions being equal, the price may increase by around 10% -15% for every additional 100mm of travel. Running speed and efficiency: The running speed and production efficiency of the punch press are also important for price evaluation. Punching machines with higher stamping frequency can produce more products per unit time and have higher value. For example, some high-speed punching machines can punch 100-200 times per minute, which is 30% -80% more expensive than ordinary punching machines (which punch 30-60 times per minute), even second-hand high-speed punching machines. 3. Equipment age and usage status Service life: Punching machines with a shorter service life are relatively more expensive. Generally speaking, for every year of reduced service life, the price may increase by 5% -10%. For example, the price of a punch press that has been used for 3 years will be about 10% -20% higher than the same punch press that has been used for 5 years. However, this is also related to factors such as the brand and maintenance of the equipment. Running time and degree of wear: In addition to service life, actual running time and degree of equipment wear have a more direct impact on price. Evaluate by checking the wear of key components such as sliders, guide rails, crankshafts, etc. If the key components wear slightly, the equipment price will be higher; And for equipment with severe wear and tear, the price will be significantly reduced. For example, if the wear of the guide rail exceeds a certain limit (such as a guide rail gap greater than 0.1mm), it may reduce the price of the punch press by 30% -50%. At the same time, punch presses with short operating time and low wear and tear have relatively more reliable electrical and control systems, and their prices will also be reflected. Appearance condition: Punching machines with good appearance, no obvious rust, paint peeling, or collision marks will be more expensive. The appearance condition can to some extent reflect the usage environment and maintenance situation of the equipment. A clean looking punch press may also have its internal mechanical and electrical systems well maintained. The price of second-hand punch presses with good appearance may be 10% -15% higher than equipment of the same model with poor appearance. 4. Market supply and demand relationship and regional factors Market demand: When there is a strong demand for a certain type or tonnage of punch press in the market, prices will rise. For example, during the peak season of the automotive parts processing industry, the demand for large stamping tonnage (such as 160 tons or more) punching machines increases, and the price of such equipment in the second-hand market will also rise accordingly, which may be 10% -20% higher than the off-season. On the contrary, when market demand is weak, prices will decrease. Regional differences: The prices of second-hand punching machines may vary in different regions. In industrialized areas, the supply and demand for second-hand punching machines are relatively large, and the prices are relatively stable. In some areas with relatively underdeveloped industries, due to the small number of equipment and low market competition, prices may be higher or lower. At the same time, transportation costs can also affect prices. For areas far from the equipment sales location, transportation costs need to be considered, which may increase the purchase price. For example, purchasing punching machines from the south and transporting them to the north may increase the total cost of the equipment by 5% -10% due to transportation costs. 5. Equipment configuration and accessory situation Standard configuration integrity: The standard configuration of the punch includes clutch, brake, lubrication system, electrical control system, etc. If these configurations are complete and functioning properly, the device price will be higher. For example, a high-performance electrical control system can improve the automation level and operational safety of punching machines, and the lack or damage of these configurations can reduce equipment prices by 10% -20%. Attachment situation: Special accessories attached to the equipment (such as automatic feeding devices, rapid mold replacement devices, etc.) can also affect the price. These attachments can improve the production efficiency and processing convenience of the punch press. The price of second-hand punching machines with advanced accessories will be 20% -30% higher than similar equipment without accessories.

When purchasing a second-hand punch press, you need to pay attention to the following aspects: 1. Equipment performance inspection Accuracy testing -Check the stroke accuracy of the slider, including whether the up and down movement of the slider is vertical, which will directly affect the quality of the stamped parts. A dial gauge can be used to measure the perpendicularity between the slider and the worktable. Under normal circumstances, the perpendicularity error should be controlled within a certain range, such as ± 0.1mm/300mm stroke. -The flatness of the workbench is also crucial, as an uneven workbench can cause unstable placement of the workpiece and affect stamping accuracy. Use a level to check the flatness of the workbench, generally requiring a flatness error between 0.05-0.1mm. Operation status check -Conduct an air run test to observe the operation of the punch press in an unloaded state. Pay attention to whether there is any abnormal noise. The normal operation sound of the punch should be smooth and regular. If there are sharp friction sounds, impact sounds, etc., it may indicate wear or looseness of internal parts. -Check if the movement speed of the slider is uniform. Uneven movement speed of the slider in the punch press can cause instability in the stamping process. Meanwhile, observing the braking performance of the punch press, a good braking system should be able to stop the slider from moving in a short period of time, ensuring safe operation. Stress testing -If possible, conduct a pressure test to check if the punch can reach the nominal pressure tonnage. Pressure sensors and other tools can be used to measure the actual pressure, ensuring that the pressure meets the processing requirements. For punch presses with insufficient pressure, it may not be possible to complete stamping work on thicker or harder materials. 2. Equipment quality assessment Appearance inspection -Check if there are any obvious deformations, cracks, or repair marks on the punch press body. The integrity of the body structure is crucial for the stability and service life of the punch press. If the body undergoes deformation, it may affect the accuracy and safety of the punch press. -Check the surface rust of the punch press. Slight surface rust can be cleaned, but severe rust may have already corroded the internal parts. Meanwhile, observing whether the paint has peeled off can also indirectly reflect the equipment's usage environment and maintenance situation. Component inspection -Focus on inspecting the wear of key components such as crankshafts, connecting rods, sliders, and guide rails. Worn parts will reduce the performance and accuracy of the punch press. For example, rail wear can cause the slider to move unevenly, increasing maintenance costs. You can manually move the slider to feel the smoothness of its movement and determine the degree of wear on the guide rail. -Check the working status of the clutch and brake, which are related to the start, stop, and safe operation of the punch press. Check if they can bind and separate properly, and if there is any slipping or malfunction. 3. Equipment history investigation Service life and frequency -Understanding the service life of punching machines, generally speaking, punching machines with shorter service life have relatively better performance and accuracy. At the same time, inquire about the frequency of device usage, such as the number of stamping operations per year. If the device is used too frequently, it may lead to increased wear and tear on critical components. Usually, the economic service life of a punch press is around 10-15 years, but the specific situation also depends on factors such as equipment brand and maintenance. Maintenance and upkeep records -Require the seller to provide maintenance records of the equipment, including the time and content of regular maintenance, as well as information on the main components replaced. Good maintenance can extend the service life of equipment and improve its reliability. If the equipment lacks regular maintenance, it may hide various potential faults. Repair history -Inquire whether the equipment has experienced any major malfunctions, such as crankshaft damage, electrical system failures, etc. Understand the cause of the malfunction, repair time, and the recovery situation after repair. If the equipment has frequent maintenance records, especially those involving critical components, it may affect the performance and stability of the equipment. 4. Safety device inspection Protective fence and light curtain -Check if the protective fence around the punch press is complete and secure. The height and clearance of the fence should meet safety standards and effectively prevent operators from coming into contact with hazardous areas. A light curtain is a safety protection device, and when the operator's hands or body obstruct the light curtain, the punch press should immediately stop running. Check the sensitivity and reliability of the light curtain to ensure its normal operation. Emergency stop button -Check if the position of the emergency stop button is easy to operate and if the button is sensitive. In emergency situations, operators should be able to quickly press a button to stop the punch press and prevent accidents from occurring. At the same time, test the connection between the emergency stop button and the punch control system to ensure that it can effectively control the operation status of the punch. 5. Price and after-sales service Price evaluation -Before purchasing, conduct research on the prices of punching machines of the same brand, model, and similar color in the market. Consider factors such as device performance, service life, and configuration to evaluate whether the price quoted by the seller is reasonable. To avoid losses due to excessively high prices, while also being alert to potential issues with low-priced equipment. after-sale service -Understand whether the seller provides after-sales service, such as the warranty period, warranty scope, and repair response time of the equipment. For second-hand equipment, some sellers may provide a certain period of warranty service, which can provide buyers with certain protection. At the same time, ask the seller if they can provide technical support, including equipment operation training, troubleshooting guidance, etc.

The price of second-hand punching machines varies greatly due to factors such as brand, model, tonnage, and degree of newness. The following is a rough price range: 1、 Small punch press: 16 tons: About 80% new domestically produced second-hand punching machines weighing 16 tons, with prices generally ranging from 12000 to 15000 yuan. 25 tons: Used punching machines weighing 25 tons are more common, with prices typically ranging from 5000 to 15000 yuan. 2、 Medium sized punch press: 63 tons: The price is approximately 20000 to 50000 yuan. 80 tons: 80 tons of second-hand punching machines such as Jinzhong Gongding punching machines, with prices generally ranging from 30000 to 80000 yuan depending on the specific situation 3、 Large punch press: 160 tons: The prices of large second-hand punching machines weighing 160 tons and above vary greatly, ranging from tens of thousands to hundreds of thousands of yuan. 800 tons: 800 tons forging machine tool from Frunzesh, Russia, priced at approximately 1.1 million yuan 4、 Numerical Control Punching Machine: The price of numerical control punching machines is relatively high. 90% of the new Japanese Murata MOTORUM numerical control punching machine and M2048TE rotary tower punching machine are priced at 88888.88 yuan

The quality of second-hand punching machines can be evaluated from the following aspects: Appearance inspection: Check the overall appearance of the punch press, including whether there are obvious deformations, cracks, rust, and other conditions on the body. If there are serious appearance issues, it may indicate that the device has been affected by improper use or harsh environments, which in turn affects its internal structure and performance. Accuracy testing: For punch presses, accuracy is crucial. Professional testing tools such as dial indicators can be used to detect key accuracy indicators such as the accuracy of the slide stroke, the flatness of the worktable, and the perpendicularity between the slide and worktable of the punch press. Punching machines with substandard accuracy may lead to dimensional deviations and quality issues in the processed parts. Run test: Conduct air load test and load test when conditions permit. Observe whether the various parameters of the punch press during operation, such as slider movement speed, punching force, noise, vibration, etc., are normal. Abnormal noise and vibration may indicate potential internal faults in the equipment. Check the wear condition of components: Focus on inspecting the wear degree of key components of the punch press, such as sliders, guide rails, crankshafts, connecting rods, etc. Overly worn components can reduce the performance and service life of the punch press, increase maintenance costs and downtime. Electrical system inspection: Check the electrical control system of the punch press, including motors, control cabinets, button switches, sensors, etc. Ensure that electrical components are intact, wiring connections are secure, the control system operates stably, and there are no fault alarm signals. Understand equipment maintenance records: Request maintenance records of the punching machine from the seller to understand their past maintenance situation, including regular maintenance time, replaced parts, and other information. Good maintenance records help to assess the usage status and potential issues of equipment.

There are several factors that affect the price of second-hand machining centers, including: 1. Brand and Model Brand influence: Processing centers of well-known brands usually have higher prices. For example, brands such as DMG MORI from Germany and Mazak from Japan enjoy a high reputation in the global machine tool industry. These brands, with their advanced technology, high-precision manufacturing processes, and reliable quality, offer relatively high prices even for second-hand equipment. Because their brand value is reflected in the performance, stability, and service life of the equipment, users have high recognition of these brands, and the market demand is also large. Model differences: Different models of machining centers have differences in functionality, accuracy, processing range, and other aspects, which affect the price. For example, machining centers with five axis linkage function are more expensive than three-axis machining centers. Five axis machining centers are capable of processing more complex parts, with higher requirements for equipment's mechanical structure, CNC system, and technical content. Therefore, their second-hand prices will correspondingly increase. Similarly, large machining centers (such as gantry machining centers) are generally more expensive than small vertical machining centers due to their large machining dimensions and strong load-bearing capacity. 2. Equipment performance and accuracy Machining accuracy: Machining accuracy is a key indicator for measuring the quality of machining centers. High precision machining centers have higher second-hand prices. For example, devices with positioning accuracy within ± 0.005mm and repeat positioning accuracy within ± 0.003mm will have a significant price difference compared to devices with lower accuracy. High precision equipment can meet strict size and shape requirements when processing precision parts such as aerospace components, high-end molds, etc., and its value is naturally higher. Processing efficiency: The processing efficiency of equipment can also affect prices. A machining center with high spindle speed, fast feed system, and efficient tool changing device can complete more machining tasks per unit time and improve production efficiency. These devices will also have correspondingly higher prices in the second-hand market, as they can bring higher economic benefits to users. 3. Equipment age and usage status Service life: Generally speaking, machining centers with shorter service life are more expensive. The longer the device is used, the greater the degree of wear on its components and the higher the possibility of performance degradation. For example, a machining center that has been in use for 2-3 years may be 30% -50% more expensive than the same equipment that has been in use for 8-10 years. Running time and processing workload: In addition to the service life, the actual running time and processing workload of the equipment are also crucial. If the equipment runs for a long time and has heavy processing tasks, its mechanical components (such as guide rails, screws, spindles, etc.) will wear more severely, and there may also be more potential faults in the electrical and numerical control systems. In this case, the equipment price will decrease. Equipment condition and appearance: Equipment with good appearance, no obvious collision or corrosion marks is relatively expensive. Although appearance does not fully represent the intrinsic quality of the device, it can to some extent reflect the usage environment and maintenance situation of the device. A machining center with a clean appearance and good maintenance may also have better maintenance of its internal mechanical and electrical systems, making it more cost-effective. 4. Equipment configuration and accessories Standard configuration integrity: The standard configuration of the machining center includes a tool magazine, automatic tool changer, cooling system, lubrication system, etc. If these configurations are complete and functioning properly, the device price will be higher. For example, a large capacity, high-speed tool changing tool magazine can improve machining efficiency, and the lack or damage of these configurations can reduce equipment prices. Attachment situation: Special accessories attached to the equipment (such as measuring probes, fourth or fifth axis rotating workbenches, etc.) may also affect the price. These attachments can expand the functionality of the device, enabling it to complete a wider range of processing tasks. The price of second-hand machining centers with advanced accessories will be much higher than that of similar equipment without accessories. 5. Market supply and demand relationship and regional factors Market demand: When there is a strong demand for a certain type or brand of machining center in the market, prices will rise. For example, during the peak season of the mold processing industry, the demand for high-precision mold processing centers increases, and the price of such equipment in the second-hand market will also rise accordingly. On the contrary, when market demand is weak, prices will decrease. Regional differences: Second hand equipment prices may vary in different regions. In industrialized areas, the supply and demand for second-hand processing centers are relatively high, and prices are relatively stable. In some areas with relatively underdeveloped industries, due to the small number of equipment and low market competition, prices may be higher or lower. At the same time, transportation costs can also affect prices. For areas far from the equipment sales location, transportation costs need to be considered, which may increase the purchase price. 6. After sales service and technical support After sales service commitment: If the seller can provide a certain period of after-sales service, such as warranty, repair services, etc., the equipment price will be relatively high. Because this can reduce the worries of buyers and lower the risks during device use. Technical support capability: The technical support capability of the seller or supplier is also important. If they can provide technical support such as equipment operation training and troubleshooting guidance, the value of the equipment will be increased and the price will correspondingly rise.

The budget for purchasing a second-hand machining center varies due to various factors. Usually, domestically produced second-hand small vertical machining centers, such as the 850 model, are priced at around 80000 to 160000 yuan. For example, the 850 machining center sold in Huizhou, Guangdong is priced at 16000 yuan, and the VMC850 vertical machining center in Qingdao is priced at 119000 yuan Domestic medium-sized second-hand machining centers, such as 1060, 1160, etc., have prices ranging from 150000 to 300000 yuan depending on their configuration and precision. For example, the 95 new 1160 machining center transferred from Guangzhou costs 150000 to 250000 yuan Large domestic second-hand gantry machining centers are relatively expensive, with gantry machining centers ranging from 2 to 5 meters costing around 300000 to 1 million yuan. For example, the HaiTian gantry machining center in Qingdao, which is 2 * 5 meters long, costs 950000 yuan In terms of imported brands, second-hand vertical machining centers from Japanese brands such as Mazak and German brands such as Demag are often priced between 200000 and 500000 yuan, even for older models. For example, the second-hand Mazak NEXUS 510C vertical machining center that has been transferred is negotiable, but usually not less than 200000 yuan; And its high-end five axis linkage machining centers, such as Demagi DMU75mono BLOCK, may cost over 1 million yuan or even higher, and the specific details need to be discussed face-to-face

The quality and performance of second-hand machining centers can be evaluated from the following aspects: 1. Evaluation of machining accuracy Dimensional accuracy testing -Standard inspection tools such as calipers, micrometers, coordinate measuring instruments, etc. can be used to measure the dimensions of processed parts. Choose some simple geometric shapes, such as cubes or cylinders, for processing, and then compare the deviation between the design dimensions and the actual processing dimensions. For example, for precision machining centers, the dimensional accuracy deviation should be controlled within ± 0.01mm. -Check the positioning accuracy and repeatability accuracy of the equipment. Positioning accuracy refers to the degree to which the actual position of moving parts such as the machine tool worktable is close to the commanded position, while repeat positioning accuracy refers to the accuracy of locating the same position multiple times under the same conditions. This can be measured using professional equipment such as laser interferometers. Generally speaking, the positioning accuracy of high-precision machining centers can reach ± 0.005- ± 0.01mm, and the repeated positioning accuracy can reach ± 0.003- ± 0.005mm. Shape accuracy check -Observe the shape accuracy of processed parts, such as flatness, straightness, roundness, cylindricity, etc. For flat machining, a knife edge ruler and a feeler gauge can be used to check the flatness; For cylindricity, a roundness meter can be used for measurement. Taking flatness as an example, the flatness error of the plane machined by a high-precision machining center should be controlled within 0.01mm. Surface roughness assessment -Measure the surface roughness after processing using a roughness meter. Surface roughness refers to the unevenness of the machined surface with small spacing and small peaks and valleys. Different processing techniques and parameters can affect surface roughness. For general machining centers, the surface roughness Ra value can reach 1.6-3.2 μ m, while precision machining centers can reach 0.8-1.6 μ m. 2. Mechanical system inspection Spindle system -Check the radial runout and axial displacement of the spindle. A dial gauge can be used for measurement. Place the dial gauge head in contact with the end of the spindle, rotate the spindle, and observe the swing range of the dial gauge pointer. In general, the radial runout of the spindle should be less than 0.005mm, and the axial displacement should be less than 0.003mm. -Check the speed range and stability of the spindle. Run the spindle at different speeds and observe for any abnormal vibrations and noise. A stable spindle speed is crucial for ensuring machining quality, especially during high-speed cutting. -Check if the tool clamping device of the spindle is working properly. Ensure that the tool can be firmly installed on the spindle without loosening during the machining process. feed system  -Check the motion accuracy of each axis (X, Y, Z, etc.). Manually move the workbench and feel the smoothness of the movement, whether there are any lagging or crawling phenomena. Check the guide rails and screws of each axis for wear, scratches, and other conditions. Severely worn guide rails and screws can affect motion accuracy, and can generally be preliminarily judged by observing surface gloss, checking clearances, and other methods. -Evaluate the performance of the drive motor in the feed system. The motor should be able to provide sufficient power and respond quickly to ensure feed rate and accuracy during the machining process. 3. CNC system evaluation System function check -Verify the basic functions of the CNC system, such as program input, editing, storage, and execution. Ensure the normal input of various machining instructions, including linear interpolation, arc interpolation, tool compensation, and other functions. -Check if the operating interface of the CNC system is clear, intuitive, and easy to operate. The friendliness of the user interface can affect the efficiency of programming and operation. -Test the auxiliary functions of the CNC system, such as automatic tool changing, coolant control, chip removal control, etc. For example, checking the tool changing speed, accuracy, and reliability of the automatic tool changing system is crucial for improving machining efficiency in machining centers. System stability testing -Run the CNC system for a long time and observe whether there will be any abnormal situations such as crashes, errors, program loss, etc. A complex machining program can be run in a CNC system for several hours to check the stability of the system. -Check the anti-interference ability of the CNC system. Turn on some equipment around the machine tool that may generate electromagnetic interference, such as welding machines, large motors, etc., and observe whether the CNC system can work normally. 4. Inspection of tool magazine and tool changing system Tool storage capacity and tool specifications -Confirm whether the capacity of the tool magazine meets the processing requirements. Different machining tasks require different quantities and types of cutting tools, and the tool magazine capacity should be selected according to the actual situation. At the same time, check the maximum size and weight of the tools that can be accommodated in the tool magazine to ensure that the required tools can be installed. Tool changing speed and accuracy -Test the tool changing speed of the tool changing system, which directly affects the machining efficiency. Observe whether the tool changing process is smooth and accurate, and whether there are any situations such as tool dropping or loose clamping. The reliability of the tool changing system can be checked through multiple manual and automatic tool changing operations. 5. Inspection of working fluid and lubrication system Working fluid system -Check the cleanliness of the working fluid tank, there should be no excessive impurities or metal shavings in the working fluid. The cleanliness of the working fluid can affect the machining quality and the service life of the machine tool. -Check the working status of the working fluid pump, including whether the flow rate and pressure are normal. The working fluid pump should be able to provide sufficient working fluid flow to ensure cooling and chip removal in the machining area. -Check if the filtration system of the working fluid is effective. A good filtration system can remove impurities from the working fluid and extend its service life. lubrication system -Check if the oil level of the lubrication system is normal and if the quality of the lubricating oil is good. Regular lubrication is the key to ensuring the normal operation of machine tool mechanical components. -Check whether the oil pump of the lubrication system is working properly and whether the lubricating oil can be evenly distributed to various parts that need lubrication, such as guide rails, screws, etc.

Here are some well-known second-hand machining center brands and models: 1、 Imported brand DMG MORI: cxgamma1250tc vertical machining center, equipped with five axis linkage function, using high-speed spindle and high-precision linear guide rail, suitable for automotive parts, aerospace, mold manufacturing and other fields; The DMU75monoBLOCK machining center has a compact structure, high precision, good dynamic performance, and machining stability, and can be used for the machining of complex parts Mazak: VTC-200BN vertical machining center, with the characteristics of high precision and high speed, can achieve efficient cutting processing, suitable for various mechanical processing industries; The VCN series vertical machining center has excellent performance in precision retention, machining efficiency, and can meet the machining needs of different users Makino Makino: A99 horizontal machining center, is one of Makino's classic models, with the characteristics of high precision and high rigidity, suitable for processing box type parts, etc; V22, V33 and other types of machining centers have wide applications in mold manufacturing and other fields due to their high-speed and high-precision machining performance Okuma: MCR-BII 2540 gantry machining center adopts advanced technology and structural design, with the characteristics of high rigidity, high precision, and high machining efficiency, suitable for the machining of large parts; The MCM25 18i-MB machining center has a powerful CNC system that can achieve high-precision machining control 2、 Domestic brand Shenyang Machine Tool: VMC2010 vertical machining center, with a large worktable size, can meet the machining needs of large-sized parts and is suitable for various industries; The machining centers of models such as 1000B and 850E have high cost-effectiveness and are widely used in the domestic market Haitian: 3225 machining center, equipped with Farac MD Mitsubishi M70 system, has good stability and machining accuracy, and can be used for the machining of general mechanical parts Yongjin: YCm-V65A machining center, this model adopts Fanuc system, with high machining accuracy and efficiency, suitable for the machining of small and medium-sized parts

When purchasing a second-hand machining center, the following points should be noted: 1. In terms of equipment performance Processing accuracy testing -To check the positioning accuracy and repeatability accuracy of the machine tool. Sellers can be required to provide accuracy testing reports for their devices, or they can conduct simple testing themselves. For example, using professional tools such as laser interferometers to measure the positioning accuracy of each axis, under normal circumstances, the positioning accuracy of high-precision machining centers can reach ± 0.005mm - ± 0.01mm, and the repeated positioning accuracy can reach ± 0.003mm - ± 0.005mm. -Process test specimens to test shape accuracy and surface roughness. For example, processing a cube specimen, observing its flatness, verticality, and other shape accuracy indicators, while checking whether the surface roughness after processing meets the requirements. For precision machining centers, the surface roughness Ra should be able to reach 0.8-1.6 μ m. Mechanical transmission system inspection -Check the wear of the guide rail and screw. Manually move the workbench and feel for any lag, looseness, or abnormal noise. For ball screws, severe wear can affect transmission accuracy. Generally, a preliminary judgment can be made by observing the gloss and wear marks on the surface of the screw. A severely worn screw may need to be replaced, which will increase additional costs. -Check the accuracy and stability of the spindle. It can be evaluated by measuring the radial runout and axial displacement of the spindle. Under normal circumstances, the radial runout of the spindle should be less than 0.005mm, and the axial displacement should be less than 0.003mm. Meanwhile, observe whether there is any abnormal vibration of the spindle during high-speed rotation, which may be caused by bearing damage or imbalance. Numerical Control System Inspection -Confirm the brand, version, and functionality of the CNC system. There are differences in the operating interface, programming functions, and control accuracy among different brands and versions of CNC systems. For example, well-known brands such as Siemens and Fanuc have powerful and stable CNC systems. -Check whether the operation of the CNC system is normal, including program input, editing, storage, and execution functions. Test whether the manual and automatic control of each axis, as well as various auxiliary functions such as tool compensation and coordinate system setting, are effective. You can also check if the system has any fault prompts or historical fault records, which can help understand potential issues with the equipment. 2. In terms of device history Service life and frequency -Understand the service life of the equipment. Generally speaking, equipment with a shorter service life has better performance and accuracy. At the same time, inquire about the frequency of device usage, such as the number of processing hours per year. If the device is used too frequently, it may lead to increased wear and tear on critical components. Usually, the economic service life of machine tools is around 10-15 years, but the specific situation also depends on factors such as equipment brand and maintenance. Maintenance and upkeep records -Require the seller to provide maintenance records of the equipment, including the time and content of regular maintenance, as well as information on the main components replaced. Good maintenance can extend the service life of equipment and improve its reliability. If the equipment lacks regular maintenance, it may hide various potential faults. Repair history -Inquire whether the equipment has experienced any major malfunctions, such as spindle damage, electrical system failures, etc. Understand the cause of the malfunction, repair time, and the recovery situation after repair. If the equipment has frequent maintenance records, especially those involving critical components, it may affect the performance and stability of the equipment. 3. Appearance and configuration Appearance inspection -Check the overall appearance of the device for obvious collision, deformation, rust, and paint peeling. These surface issues may suggest that there is also damage inside the device. For example, if there are collision marks on the appearance of the equipment, it may cause damage to the structural accuracy of the machine tool. Configuration check -Confirm whether the standard configuration of the equipment is complete, such as whether the tool magazine capacity and tool specifications meet the requirements, whether the automatic tool changing device is working properly, and whether the auxiliary systems such as the cooling system and lubrication system are intact. Check the tool changing speed and accuracy of the tool magazine. For machining centers, fast and accurate tool changing is one of the key factors in improving machining efficiency. 4. Price and after-sales aspects Price evaluation -Before purchasing, conduct research on the prices of processing centers of the same brand, model, and similar color in the market. Consider factors such as device performance, service life, and configuration to evaluate whether the price quoted by the seller is reasonable. To avoid losses due to excessively high prices, while also being alert to potential issues with low-priced equipment. after-sale service -Understand whether the seller provides after-sales service, such as the warranty period, warranty scope, and repair response time of the equipment. For second-hand equipment, some sellers may provide a certain period of warranty service, which can provide buyers with certain protection. At the same time, ask the seller if they can provide technical support, including equipment operation training, troubleshooting guidance, etc.

1. Mechanical structure of the machine factors Guideway accuracy: Sodick EDM machine tool guideway is the electrode wire and workpiece relative movement of the benchmark. If the guideway has wear and tear, straightness and flatness errors, it will directly affect the motion accuracy of the electrode wire. For example, for every 0.01mm increase in the straightness error of the X and Y axis guideways, the machining accuracy may decrease by about 0.02 - 0.03mm. High-precision Sodick machines usually use high-precision linear guideways, and their accuracy is ensured by regular maintenance and calibration. Screw rod accuracy: The accuracy of the screw rod is critical to the positioning accuracy of the electrode wire. Pitch error and cumulative error of the silk rod can lead to inaccurate positioning of the electrode wire during movement. For example, a pitch error of 0.005mm in the screw rod will cause the positioning error of the electrode wire to increase significantly after a long stroke movement, thus affecting the machining dimensional accuracy. Worktable precision: the flatness and parallelism of the worktable will affect the clamping accuracy of the workpiece. If the table flatness is poor, the workpiece will be tilted after clamping, which will lead to deviation of the perpendicularity between the machining surface and the electrode wire during machining, so that the shape accuracy of the machined parts will be poor, such as tilting in plane machining, and cylindrical machining with over-degree of cylindricity. 2. Electrode wire factor Electrode wire diameter: the precision and consistency of the diameter of the electrode wire will affect the size of the discharge gap, which in turn affects the machining accuracy. Different diameters of the electrode wire, the discharge gap is different. For example, the discharge gap of 0.1mm electrode wire is generally around 0.02 - 0.03mm, and the discharge gap of 0.2mm electrode wire may be 0.03 - 0.04mm. If the diameter of electrode wire is not uniform, it will lead to unstable discharge gap, and the machining accuracy will be reduced. Electrode wire tension: Uneven or unstable electrode wire tension will cause the electrode wire to shake during the discharge process. Appropriate tension can ensure the straightness of the electrode wire and improve the machining accuracy. If the tension is too small, the electrode wire jitter increases, which will make the discharge position unstable, and the machining accuracy may be reduced by 0.01 - 0.02mm; while the tension is too large, which may lead to electrode wire breakage or excessive wear of machine parts. Electrode wire material and quality: The material of the electrode wire (e.g. brass, galvanised copper, etc.) affects its electrical conductivity and corrosion resistance. Good quality electrode wire can provide more stable discharge performance, which is conducive to improving machining accuracy. Poor quality electrode wire may have uneven local discharge, resulting in increased roughness of the machined surface and decreased dimensional accuracy. 3. Discharge parameter factors Discharge energy: the size of the discharge energy is directly related to the degree of discharge corrosion. If the discharge energy is too large, it will cause the discharge pit to be too large and too deep, so that the machining accuracy is reduced and the surface roughness becomes worse. For example, when processing precision parts, too high a discharge energy may cause the dimensional accuracy to drop by 0.02 - 0.03mm, and the surface roughness Ra value to rise from 0.4μm to more than 0.8μm. Too little discharge energy, on the other hand, will slow down the machining speed. Discharge pulse width and interval: Pulse width determines the duration of each discharge, and pulse interval affects the frequency of discharge. A suitable pulse width and interval can ensure the stability of the discharge process. If the pulse width is too long or the interval is too short, it is easy to produce arc discharge, burn the workpiece and electrode wire, so that the machining accuracy and surface quality decline. 4. Working fluid factor Cleanliness of the working fluid: the working fluid will affect the stability of the discharge if it contains more metal shavings and impurities. Dirty working fluid will make the insulation of the discharge gap decrease, easy to produce short-circuit discharge, resulting in reduced machining accuracy. For example, too high a concentration of metal chips in the working fluid may reduce the machining dimensional accuracy by about 0.01 - 0.02mm. Performance of the working fluid: the conductivity, viscosity and other properties of the working fluid will also have an impact on the machining accuracy. Conductivity is not suitable working fluid will affect the transfer of discharge energy, viscosity is not suitable will affect the working fluid chip removal and cooling effect. For example, if the viscosity of the working fluid is too high, the chip removal is not smooth, which will make the metal chips in the discharge gap accumulate and affect the machining accuracy. 5. Control system factors Precision of the CNC system: The CNC system of Sodick EDM controls the movement trajectory of the electrode wire and the discharge parameters. A high-precision CNC system can achieve precise interpolation operations to ensure that the electrode wire moves according to the preset trajectory. If the interpolation precision of the CNC system is low, it will lead to the deviation of the movement trajectory of the electrode wire and reduce the machining precision. For example, in the processing of complex shaped parts, the interpolation error of the CNC system increases by 0.001mm, the machining shape accuracy will be significantly affected. Feedback and compensation mechanism: a good control system has a feedback and compensation function, which can monitor the position of the electrode wire, discharge state, etc. in real time and compensate accordingly. If the feedback and compensation mechanism is not sensitive or inaccurate, for example, when the temperature changes lead to thermal deformation of the machine tool, the position of the electrode wire can not be compensated in time, which will affect the machining accuracy.

1. Dimensional accuracy     Sodick EDM machine tools have excellent performance in dimensional accuracy. Under good machining conditions, its machining accuracy can reach ±0.001 - ±0.005mm, for example, when machining some small parts of precision moulds, such as inserts of mobile phone moulds, the dimensional accuracy can be controlled stably within ±0.003mm. This is thanks to Sodick's advanced CNC system and high-precision mechanical structure, which can precisely control the movement trajectory of the electrode wire. 2. Shape accuracy    For shape accuracy, indicators like cylindricity and flatness can also reach a high level. In the processing of cylindrical parts, the cylindricity can reach 0.002 - 0.005mm. taking the processing of some small shaft parts in the aerospace field as an example, through the precision machining of Sodick EDM, the cylindricity of the parts can reach a very high standard and meet the requirements of high-precision assembly.    In terms of flatness, the flatness error after machining can be controlled between 0.003 - 0.008mm, which is very important for the processing of some electronic component moulds with strict requirements on flatness. 3. Surface roughness    Sodick EDM can achieve excellent surface roughness. Its surface roughness after processing can reach a value of Ra 0.1 - 0.8 μm. For example, in the processing of some optical moulds or medical parts, by optimizing the processing parameters, such as adjusting the discharge energy, electrode filament tension and walking speed, etc., the surface roughness can reach Ra 0.2 μm or so, to achieve the effect of similar to the mirror, reducing the subsequent polishing and other surface treatment processes.

1. Electrical discharge principle   Sodick EDM adopts the principle of electric spark discharge machining. In processing, the electrode wire (generally copper wire and other conductive materials) and the workpiece to be processed are connected to the two poles of the pulse power supply. When the distance between the electrode wire and the workpiece is small to a certain extent (generally a few microns to tens of microns), the electric field strength between the poles will reach a very high value, so that the working fluid (usually deionised water or EDM special working fluid) medium is penetrated, the formation of discharge channels.    The electrons in the discharge channel run to the positive pole at high speed, and the positive ions run to the negative pole, and the electric energy is instantly transformed into heat energy, and the temperature can be as high as 10000 - 12000℃, which makes the electrode wire and the local metal materials on the surface of the workpiece melt or even vaporise rapidly. 2. Material removal process    Due to the high temperature generated by the discharge, the metal is melted and vaporised, and under the action of the explosive force of the discharge, the melted and vaporised metal is thrown away from the electrode wire and the surface of the workpiece, forming a small discharge crater.    As the pulse power supply continuously sends out pulse signals, the discharge between the electrode wire and the workpiece is continuously carried out, and countless discharge craters overlap each other, so that the material of the workpiece is finally removed according to the predetermined shape and the cutting process is realised. 3. Role of electrode wire movement    The electrode wire of a Sodick EDM moves slowly (the origin of the name ‘EDM’), which is different from that of a Rapid Walking Wire. The slow movement of the electrode wire plays an important role in that it constantly updates the discharge position of the electrode wire and prevents the electrode wire from being repeatedly discharged in the same position, which would lead to excessive losses.    The new electrode wire continuously enters the discharge area, which can maintain a stable discharge state, and is conducive to improving processing accuracy and surface quality. At the same time, the movement of the electrode wire can also bring the metal chips generated by the discharge out of the discharge area, preventing the metal chips from accumulating in the discharge gap and affecting the subsequent discharge machining. 4. Function of working fluid    The working fluid plays the roles of cooling, chip removal and insulation in the process of Sodick EDM cutting. In terms of cooling, it can take away a large amount of heat generated by the discharge, preventing the electrode wire and workpiece from being deformed or damaged due to overheating.    Chip removal, the flow of the working fluid can discharge the metal chips generated by the scouring away, so that the discharge gap to keep clean, in favour of the discharge continues. Insulation role is to ensure that the discharge occurs only in the narrow gap between the electrode wire and the workpiece, and will not generate discharge in other unwanted places.