How to evaluate the performance and quality of a used jogging wire?

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.