Most popular to provide better process control for

2022-09-22
  • Detail

The development of high-precision machine tools, detection technology on machine tools and non-contact tool setting technology provides powerful tools for the automation and rapid prototyping of mold processing

the driving mechanism used for faster, labor-saving and more flexible production makes the industrial focus deviate from the traditional post process quality management. In most workshops, the most expensive work that cannot create value is the inspection of parts. Unqualified parts are a waste of time, money and manpower. Now the attention is not focused on the late detection, but shifted to the early prevention. Its purpose is to produce 100% qualified products with special tight fitting tolerance and minimum processing time from the beginning. Under this purpose, various practical technologies have been applied to machine tools to achieve better process control. Automatic process inspection can keep the process and parts under control, so as to minimize the downtime caused by operator intervention

these improvements in process control are very critical for the mold manufacturing industry. Most mold processing has the characteristics of one-time molding, because the high cumulative error value will be transferred to the complex mold, which requires us to complete all processing at one time. At the same time, shorter delivery times and global competition also require processing molds that are faster to deal with trade protectionism. In order to minimize the interference of operators and other factors, these process control systems add a pair of monitoring eyes for mold manufacturers, which is conducive to monitoring the processing of machine tools in the long-term processing and the second and third processes

processing capacity of machine tools

in order to prevent defects, enterprises must have the ability of process documents and the ability to ensure the process accuracy of machine tools. In order to achieve this goal, it is necessary to carry out inspection in accordance with national recognized and accepted standards, such as ISO 230 standard or ASME B5.54 standard. Both of these standards require the use of ball rods and laser interferometers to test the accuracy of the machine tool according to the recommended procedures. The purpose of adopting these standards is not to stipulate that the machine tool must meet a certain accuracy, but to find out what accuracy level the machine tool can achieve. The written information of the parts stipulates that the machine tool accuracy of the enterprise must be able to produce qualified parts, and the accuracy benchmark is set in this place. After testing, you can know how high your machine tool can reach. As long as the machine tool can reach that precision benchmark, it has the ability of process processing

modern machine tools have testing and calibration technology, and can also provide this technology, so that the workshop can ensure the accuracy and normal operation of machine tools. More and more factories and large workshops have their own laser interferometers and electronic equipment, while small factories can obtain equipment and testing services by leasing at competitive prices through various channels and commercialization

in fact, telescopic ball bar detectors can be provided for any workshop for rapid detection of machine tools. The detection task can be completed in only 15 minutes to maintain the machining accuracy of machine tools. The geometric accuracy, roundness and stick slip errors, servo gain mismatch, vibration, backlash, repetition accuracy and scale mismatch of the machine tool can be accurately evaluated by ball and rod detection. Some club software can provide diagnosis of specific errors according to ISO and ASME B5.54 and b5.57 standards. Please pay attention to the following matters, and then provide a common English list, listing the sources of various errors in the order of overall impact on the accuracy of the machine tool. This enables the machine tool maintenance personnel to deal with the problem directly

the periodic Club test can keep up with the performance development trend of machine tools. Preventive maintenance is conducive to making plans in advance before the machine tool deviates from the process processing capacity. Industry generally tends to calibrate machine tools according to needs rather than time. There is no reason to take out a good machine in production for maintenance to calibrate. When any abnormal condition is found, it is still up to the testing club and the produced parts to determine. Production can continue during the testing period

on-board probe detection

the accuracy and repetition accuracy that standard machine tools can achieve today are close to the level that only CMM can achieve in the past. This function enables the machine tool itself to automatically detect the workpiece with a probe at the key processing stage. Once the measuring instrument is installed on the machine tool, the measuring probe becomes the CNC measuring meter of the operator. The detection program can be programmed as a part of the processing technology, and automatically run at each point to detect the size and position and provide necessary compensation. In this way, the operator can be exempted from using the dial indicator and plug gauge for measurement, and the error caused by the offset of fixtures, parts and tools in the control system caused by human factors can be eliminated. On machine inspection has become a part of the process. It is an improved and powerful process tool, which can produce qualified parts for the first time in the shortest production time

can be used to automatically determine the position of parts, and then establish a working coordinate system. On machine detection can reduce the setting time, improve the utilization of spindle, reduce the cost of fixture, eliminate non production manufacturing technology level and overall strength, and further improve the processing travel time. In terms of complex parts processing, it used to take 45min to debug the fixture, but now the application of the detection device only takes 45s and is all automatically operated by CNC. When machining castings or forgings, the detection device can determine the shape of the workpiece, avoid wasting time due to empty cutting, and help determine the best cutting angle of the tool. The control in the process is to use the detection device to monitor the characteristics, size and position of the machine tool in the cutting process, and verify the accurate size relationship between the various characteristics of each processing process, so as to avoid problems. The probe can be programmed, and the actual machining results of each stage can be detected according to the program, and then the tool compensation can be realized automatically, especially after rough machining or semi precision machining

reference detection is to compare the part features with a size template or a reference surface with known position and size. It enables CNC to determine the positioning gap, and then generate an offset to compensate for this gap. Before the key processing, through the detection of the imitation template, CNC can check its own positioning according to the known size of the template, and then program the offset. If the dimension template is installed on the machine tool and exposed to the same environmental conditions, the reference detection can be used to monitor and compensate the coefficient of thermal expansion. The result is a closed cycle process, which will not be affected by the operator

each machine tool has many inherent small errors in its movement and structure. Therefore, there is always a small gap between the programmed position of CNC and the real position of the tool tip, even after the two are adjusted to be quite consistent through laser compensation. Programmable artificial sample inspection is a good method to further compensate the remaining errors of machine tools. It can provide feedback for process control and make the positioning accuracy close to the specification requirements of machine tool repetition accuracy. This closed-circuit process control can make the machining accuracy of the machining center reach the machining level of boring and milling machines and other precision machine tools

many probe detection operations are accomplished by using memory resident macroinstruction programs. The update of working coordinates, the change of tool geometry and the measurement of parts are automatically determined by CNC after successfully completing the probe detection cycle. This can eliminate serious errors caused by incorrect information links or incorrect calculations. Because large and expensive workpieces are very difficult to move and time-consuming, on-board inspection is particularly beneficial to large and expensive workpieces

here, two methods can also be used to complete the reference detection, that is, the machine tool correlation detection method is used to compare the data measured on the machine with the data of the previous CMM measuring machine; Or use the imitation template detection method to compare the on-board data with the traceability imitation template of known size. When making this comparison, CNC can determine whether the machine tool has really reached the specified machining tolerance. Based on these results, we can make a wise decision and adopt the correct treatment method for the workpiece that remains on the machine tool

the strain gauge probe is detecting the injection mold of a computer mouse. This strain gauge testing technology overcomes the disadvantage of using the ordinary contact trigger probe to measure the non-uniformity, because the parts with complex geometry need to be approached from all directions. This omni-directional probe keeps the machining accuracy of western industrial tooling in Redmond, Washington between +0.0000~-0.013 mm, and the accuracy of its parts reaches 25% of the tolerance required by customers.

non contact laser tool setting

exciting light tool setting instrument provides a fast and automatic method for verifying the size of tools, especially in mold manufacturing, for checking tool wear after long-term processing, Plays a key role. Laser tool setting instrument is an effective method for high-speed and high-precision tool adjustment and tool fracture detection. It has good cost-effectiveness. In the working state, when the tool is indexed by laser beam or rotated at normal speed, it can quickly measure its length and diameter. The laser detection working with the spindle speed can identify the errors caused by the uncoordinated clamping and radial vibration of the spindle, tool and tool holder. This function cannot be achieved by using the static tool setting system. Some NC tool setting instruments can detect broken tools at the highest transverse travel, so as to further reduce the non cutting time to a minimum

when the tool moves through the laser beam, the system electronic device will detect the interruption of the laser beam and send an output signal to the controller at the same time. The NC numerical control system can accurately measure the tool with a minimum diameter of 0.2 mm anywhere in the laser beam. When the laser beam exceeds the 50% threshold and is blocked by the detected tool, the system will be triggered. The non-contact tool setting system adopts a reliable red visible diode laser under processing conditions

advanced electronic components and simplified design make non-contact tool setting replace the contact system. Because there are no moving parts, the NC numerical control system can actually be free from maintenance. This design does not have the framework and actuator required by the contact system. Some NC numerical control laser tool setters are equipped with a protection system, which is installed in a solid stainless steel device and filled with uninterrupted compressed air. Even in the process of measurement, it can prevent the invasion of pollutants, chips, graphite and coolant. These systems can almost be installed on machine tools of various sizes and shapes, without any impact on the work of the machine tools

the mature application and controllability of these technologies, such as powerful tools to improve the process level, are of great benefit to improve the automation level of mold processing and achieve better process control. They enable mold manufacturers to produce molds faster with higher geometric and dimensional accuracy, requiring little operation

Copyright © 2011 JIN SHI