Debugging and Acceptance of CNC Machine Tool Machining Center
One. Debugging of CNC machine tool processing center
The purpose of CNC machine tool debugging is to check whether the machine tool installation is stable, whether the transmission, manipulation, control and other systems are normal, sensitive and reliable.The commissioning and trial operation work is carried out according to the following steps:
◆Refuel a lubricating point according to the requirements of the manual, fill the hydraulic oil tank with hydraulic oil that meets the requirements, and connect the air source.
◆Electricity, each component is powered separately or after each component is energized for a test, then fully powered. Observe whether there is an alarm in each part, whether it is normal to observe whether each part is manual, and whether each safety device works. Even every link of the machine tool can be operated and moved.
◆ Grouting, after the initial operation of the machine tool, roughly adjust the geometric accuracy of the machine tool, and adjust the relative position of the disassembled and assembled main moving parts and the main engine. Align the manipulator, tool magazine, exchange table, position, etc. After these tasks are completed, the anchor bolts of the main engine and each accessory can be filled with quick-drying cement, and the reserved holes of the anchor bolts can be leveled.
◆Debugging, prepare various testing tools, such as precision level, standard square ruler, parallel square tube, etc.
◆Finely adjust the level of the machine tool to make the geometric accuracy of the machine tool within the allowable error range, adopt multi-point pad support, adjust the bed to level in the free state, and ensure the stability of the bed after adjustment .
◆Adjust the position of the manipulator relative to the main shaft by manual operation, and use the adjustment mandrel. When installing the tool holder with the largest weight, it is necessary to perform automatic exchange from the tool magazine to the position of the main shaft for many times, so as to be accurate and free from collision.
◆Move the workbench to the exchange position, adjust the relative position of the pallet station and the exchange workbench to achieve a stable automatic exchange of the workbench, and install the maximum load of the workbench for multiple exchanges.
◆Check whether the setting parameters of the numerical control system and the programmable controller plc device conform to the specified data in the random data, and then test the main operating functions, safety measures, and the execution of common instructions.
◆Check the working conditions of the accessories, such as the lighting of the machine tool, the cooling shield, various guard plates, etc.
After the installation and debugging of a machining center, due to its various functions, after installation, it can run automatically for a long time under a certain load, and check whether the functions of the machine tool are complete and stable. The running time can be 8 hours a day for 2 to 3 days or 24 hours for 1 to 2 days. Test machine program can be used for continuous operation.
two. Acceptance of CNC machining center
The acceptance of CNC machining center is a complex detection technology work. It includes the comprehensive performance testing of the mechanical, electrical, hydraulic and pneumatic parts of the machine tool and the testing of the static and dynamic accuracy of the machine tool. There is a special organization in our country, that is, the National Machine Tool Product Quality Inspection Center. The user’s acceptance work can be carried out according to the acceptance method of the institution, or the above-mentioned institutions can be invited to conduct the acceptance. Mainly focus on two aspects: 1.Machining center geometric accuracy inspection
The geometric accuracy of the machining center is the geometric shape error after assembly, and the inspection content is as follows:
o flatness of the worktable
o each coordinate direction The mutual perpendicularity of the movement
o the parallelism of the X-axis movement and the worktable surface
o the Y-axis movement and the parallelism of the worktable surface
o the X-axis movement Parallelism to the sides of the upper and lower grooves of the table
o axial movement of the spindle
o radial runout of the spindle hole
o movement of the spindle box along the Z coordinate direction Parallelism to the spindle axis
o Perpendicularity of the spindle rotation axis to the worktable
o Straightness of the spindle box moving in the Z coordinate direction
Commonly used The best testing tools are: precision level, square, precision square box, square ruler, collimator, dial gauge or micrometer, high-precision spindle mandrel and rigid dial gauge rod. Each geometric accuracy is tested in accordance with the acceptance conditions of the machining center. Note: The grade of the inspection tool must be one grade higher than the measured geometric accuracy. At the same time, it must be carried out when the machine tool is slightly warmed up. After the machine tool is powered on, the spindle rotates at a medium speed for 15 minutes before inspection.
2. Machine tool performance acceptance
The test items stipulated in the “General Rules for Metal Cutting Machine Tool Experiments” are as follows:
Test items
Reliability dry run Vibration, thermal deformation, static stiffness
vibration resistance, cutting noise, vibration, positioning accuracy
spindle rotation accuracy, linear motion unevenness, machining accuracy
for machine tools A comprehensive performance test requires high-precision testing instruments. In the acceptance of specific machine tools, each acceptance content can be carried out in accordance with machine tool factory standards and industry standards.
Machining center operation points
As a skilled operator, he must understand the requirements of the processed parts, the process route, and the characteristics of the machine tool before he can manipulate the machine tool to complete various processing tasks. Therefore, sort out several operating points for reference:
◆In order to simplify positioning and installation, each positioning surface of the fixture should have precise coordinate dimensions relative to the machining origin of the machining center.
◆In order to ensure that the installation orientation of the parts is consistent with the direction of the selected workpiece coordinate system and machine tool coordinate system in programming, and orientation installation.
◆It can be disassembled in a short time and changed into a fixture suitable for new workpieces. Since the auxiliary time of the machining center has been compressed very short, the loading and unloading of the supporting fixtures cannot take too much time.
◆The fixture should have as few components as possible and high rigidity.
◆The fixture should be as open as possible, the space position of the clamping element can be as low as possible, and the installation fixture can not interfere with the tool path of the working step.
◆Guaranteed to be on the spindleThe machining content of the workpiece is fully completed within the stroke range.
◆For machining centers with interactive workbenches, fixture design must prevent spatial interference between fixtures and machine tools due to movement, upholding, downholding and rotation of the workbench.
◆Try to complete all the processing content in one clamping. When it is necessary to replace the clamping point, special attention should be paid not to damage the positioning accuracy due to the replacement of the clamping point, and explain it in the process document if necessary.
◆The contact between the bottom surface of the fixture and the workbench, the flatness of the bottom surface of the fixture must be within 0.01-0.02mm, and the surface roughness is not greater than Ra3.2μm.
