What is high speed milling?
High-speed milling cannot be defined by any particular speed value, and achieving a very high value of speed or line speed is not its own goal. In contrast, high speed milling describes the method of using speed. In high speed milling, speed is a catalyst. When high-speed spindles are combined with precise positioning under high feed, high-speed cutting begins to show practical value. In mold machining, high-speed cutting makes it possible to use small-diameter tools and small depths of cut, so grooves and complex details can be machined by milling instead of EDM. In addition, the smooth surface obtained by high-speed machining makes it possible to eliminate manual polishing.
High-speed milling applications require not only the speed of the machine, but also the process used. This process is significantly different from traditional cutting requirements. High-speed milling involves many factors such as CNC machine tools, tool holder tools, cooling systems, and CAM CNC programming. This process even involves a more comprehensive and comprehensive understanding of the behavioral characteristics of the machine at different speeds. The following analysis of the similarities and differences between high-speed machining and general machining from the aspects of tool technology, machine tool technology, numerical control system performance and processing technology.
Tool technology
The tool for high-speed machining must have low chemical affinity with the workpiece material, excellent mechanical properties, chemical stability and thermal stability, and good impact and thermal fatigue resistance. Ordinary machining tool clamping technology is no longer compatible with high speed machining, and FIDIA machines use HSK tool holders. The taper and end faces of the shank are simultaneously positioned in contact with the inner taper hole and the end face of the main shaft, and the shank adopts an internal rising clamping technology to ensure the safety of the spindle at high speed.
Machine tool technology
In order to meet the requirements of high spindle speed, fast feed speed and high acceleration of moving parts of machine tools, high-speed machining machines have higher requirements than ordinary CNC machine tools in spindle unit, feed system, CNC system and mechanical system. The FIDIA high-speed milling center has excellent system functions and a good mechanical structure, which provides a reliable guarantee for the processing of high-quality molds. Typical pyramid structure, wide guide rails and low center of gravity for high speed movement of linear axes. The speed of motion of the coordinates can be accelerated from 0 to 30 m/min in 0.1 seconds. FIDIA high-speed machines are fixed with FIDIA's traditional workbench. In this way, the load-bearing capacity of the machine tool is larger than that of the movable worktable of the same specification; the inertia of the motion unit of the machine tool is constant, and the linear-axis motor is always operated under the optimal working condition, that is, the characteristics of the motor are not changed by changing the size of the machining mold; In addition, considering the special characteristics of high-speed motion, the motion inertia is minimized under the premise of ensuring the rigidity of the machine tool, so as to maximize the natural frequency of the coordinate, thereby obtaining a higher closed-loop gain, which makes the tracking error of the machine tool in high-speed machining At the minimum, the accuracy and quality of the machining are ultimately improved. FIDIA high-speed machining machines use FIDIA technology in CNC systems, drive systems, swivel pendulums and feedback encoders. As the source supplier of the end user, FIDIA ensures the quality and reliability of the whole machine.
CNC system performance
FIDIA has been a market leader in CNC systems and system integration of computational and digital profiling, and milling of complex profiles. Since 1974, FIDIA has been developing new CNC algorithms to improve the performance of milling. Over the past decade or so, FIDIA has been improving shaft control technology to reduce trajectory errors during machining. These algorithms reduce the dynamic error during machining and increase the machining feed rate and surface finish quality.
The Look-ahead function can be adapted to different conditions: machine type, type of workpiece being machined, machining requirements (roughing, semi-finishing or finishing). Different dynamic parameters can be called by G code to optimize machining performance.
Through ActiveTuning, ActiveDamping, and JerkControl, you can optimize and enhance the machining performance of high-speed cutting machines, reduce machining time and improve the surface finish quality.
These functions reduce dynamic trajectory errors and improve machining accuracy and perfect surface finish quality at high feed rates.
ActiveTuning and ActiveDamping can set optimal values ​​that match the characteristics of high-speed machine tools and do not create instability in the control loop.
The "step" type of acceleration causes oscillation, and FIDIA introduces the "JerkControl" technique to provide a gradual coordinate acceleration. Fast and smooth acceleration improves the quality of the acceleration zone.
Processing technology
Compared with ordinary processing, it can shorten the processing time, improve the production efficiency and machine utilization rate, the workpiece has small thermal deformation, high processing precision, good surface quality, wide processing technology, suitable for processing thin wall, poor rigidity and easy to generate thermal deformation. Parts. FIDIA high-speed machine tool tool cooling uses oil mist semi-dry cooling, using non-toxic vegetable lubricants, minimum lubricant supply. A thin film of oil is formed on the surface of the workpiece, which greatly improves the surface quality of the workpiece compared to the conventional method of using coolant or air cooling. Oil free bearing
In the past ten years, FIDIA has made great progress in drive technology and control systems, and has promoted the continuous innovation and performance improvement of its high-speed machining center structure. It plays a decisive role in improving the high speed, high dynamics and high precision of the machining center. In the various structural innovations of the mold processing machine, not only the rotary table but also the swinging and rotating spindle heads are applied, thereby forming various types of five-axis machining centers. The FIDIA five-axis gantry high-speed precision milling center provides technical support for machining large molds.
A ballcock (also balltap or float valve) is a mechanism or machine for filling water tanks, such as those found in flush toilets, while avoiding overflow and (in the event of low water pressure) backflow. The modern ballcock was invented by José Antonio de Alzate y RamÃrez, a Mexican priest and scientist, who described the device in 1790 in the Gaceta de Literatura Méxicana.[1] It consists of a valve connected to a hollow sealed float by means of a lever, mounted near the top of the tank. The float is often ball-shaped, hence the name ballcock. The valve is connected to the incoming water supply, and is opened and closed by the lever which has the float mounted on the end. When the water level rises, the float rises with it; once it rises to a pre-set level, the mechanism forces the lever to close the valve and shut off the water flow. This is an example of negative feedback and of proportional control.
Ball Cock, Brass Ball Bibcock, Ballcock Valve, Toilet Ballcock Valve
ZHEJIANG KINGSIR VALVE CO., LTD. , https://www.kingsir-valve.com