Large gantry milling machining center has a strong ability, the workpiece can finish more processing content after clamping at one time, and the processing accuracy is high. For the batch workpiece with medium processing difficulty, its power is 5-10 times of that of general equipment, especially it can finish the processing that many general equipment can’t finish, and it is more suitable for the single piece processing with messy shape and high precision or small and medium batch production with many kinds Use. Here is a brief introduction to the idea of gantry milling machine.
- The safe operation of large gantry milling machining center has the following points:
The working object should be clamped by pressing plate, screw or special tool. The general wrench is not allowed to add casing, so as to avoid slipping and injury.
The cutting tool must be clamped firmly, otherwise it is not allowed to drive.
Before work, check the operation of the transmission part of the machine tool, and install the baffle of the machine tool before operation.
When milling various workpieces, especially rough milling, slow cutting should be carried out at the beginning.
When moving the worktable and tool rest, loosen the fixing screw first.
When loading and unloading tools, use copper hammer or wooden mallet to gently hit to prevent tool fragments from flying out and injuring people.
In cutting, it is not allowed to change the speed and adjust the cutting tool. It is not allowed to touch or measure the workpiece by hand.
- The gantry milling machine bed is equipped with X-axis guide rail, and the gantry milling machine worktable is fixed on the bed. A gantry is erected on the movable span above the worktable, and the gantry also includes a gantry carriage, which is clamped on the x-axis guide rail. The z-axis guide rail is installed on the gantry. The crossbeam is provided with a Z-axis carriage, the crossbeam is movably clamped on the z-axis guide rail through the z-axis carriage, and the crossbeam is also provided with a Y-axis guide rail.
The milling device of the gantry milling machine is movably installed on the y-axis guide rail, so that the gantry can be milled in the three-dimensional space of X, y and Z axes under the control of the numerical control circuit control system. The CNC gantry milling machine has high precision milling, drilling, boring, cutting and other operations.
a. Reasonable selection of equipment. High machining accuracy is required. Roughing is mainly to cut off most of the machining allowance. Rough machining should be carried out on the machine tool with high power and low precision, while finish machining should be carried out on the machine tool with high precision. Rough machining and finish machining are processed on different machine tools, which can not only give full play to the equipment capacity, but also extend the service life of precision machine tools.
b. In order to ensure the machining accuracy, rough and finish machining should be carried out separately. The amount of cutting is large, because when rough machining. For some parts with high machining accuracy. After roughing and before finishing, low temperature annealing or aging treatment should be arranged to eliminate the internal stress. The cutting force and clamping force of the workpiece are large, the calorific value is large, and there is a significant work hardening phenomenon on the surface of the workpiece. There is a large internal stress in the workpiece. If the rough and rough machining is carried out continuously, the precision of the finished part will be lost quickly because of the redistribution of the stress.
c. Heat treatment process is often arranged in machining process. In order to improve the mechanical properties of parts, quenching and tempering are generally arranged after machining. The location of heat treatment process is as follows: in order to improve the cutting performance of metal, such as annealing, normalizing, quenching and tempering, it is generally arranged before machining. In order to eliminate internal stress, such as aging treatment, quenching and tempering treatment, it is generally arranged after roughing and before finishing. There are many tool materials that can be used in large spark machining, such as diamond, graphite, Cu. Cu based alloy and Cu based composite, and polymer composite is also one of the tool materials for spark machining.
At present, the components of polymer composites used in spark machining are still in the stage of research and development. Good plastic electrodes should have high thermal conductivity, good formability, low resistivity, dimensional stability in water, low coefficient of thermal expansion, and thermal cycling. Compared with graphite electrode, a tool material for spark machining, it has the advantages of low cost, and can be molded into complex geometry. Its manufacturing speed is much faster than milling. The other advantage is that the density is relatively low and the resistivity is relatively high. Therefore, the loss rate of the electrode will be relatively high, but the electrode is in the process of milling In the process of use, it can be trimmed by re molding.
At present, a conductive thermoplastic polymer composite material is used as the electrode, and air and water are used as the working medium to process or polish the surface of the workpiece. Then 60% – 65% of the solid carbon material is evenly distributed in the thermoplastic matrix material to make the electrode. The required geometry can be softened and molded repeatedly.