What are the daily maintenance and maintenance methods of the carving equipment for die processing?

The daily maintenance of engraving equipment for die cutting directly affects the accuracy, service life and processing quality of the equipment. The following systematic maintenance scheme is provided from the core modules such as machinery, electricity and cutting tools, with operation points and periodic suggestions:

I. Maintenance of mechanical system: guide rail, lead screw and transmission parts.

1. Maintenance of guide rail and slide block

Cleaning frequency: after each shift of processing (metal processing needs to be increased to every 2 hours)

Operating steps:

Dip kerosene or special cleaning agent for guide rail with a dust-free cloth, and wipe the crumbs and oil stains (especially iron filings after metal processing) on the surface of guide rail and in the groove of slider.

Check the surface of the guide rail for scratches and rust. If slight rust spots are found, use fine sandpaper (1000 mesh) for light grinding and then apply antirust oil.

Lubrication requirements:

When using automatic lubricating pump, check the oil level daily (the scale of oil window should be ≥1/2) and replenish the guide rail oil every week (ISO VG32 lubricating oil is recommended).

Manual lubrication needs to apply a thin layer of lubricating oil evenly on the guide rail surface, and run the equipment back and forth for 2-3 times to ensure the lubrication is in place.

Precautions: Avoid using viscous lubricants such as butter to prevent dust from blocking the guide rail.

2. Ball screw maintenance

Cleaning cycle: every 3 days or after 50 hours of processing.

Key operation points:

Clean the cutting fluid residue and metal powder on the surface of the lead screw with a brush, and focus on cleaning the dust-proof sealing rings at both ends of the nut.

Check the screw pitch error: run the screw manually. If there is jamming or abnormal sound, use a laser interferometer to detect the accuracy (if the error exceeds 0.02mm, it needs to be adjusted or replaced).

Lubrication mode:

Remove the dust caps at both ends of the lead screw every quarter, and apply special lead screw grease (such as lithium-based grease NLGI No.2), and the dosage should be 1/2 of the nut groove.

It is recommended to replenish grease once a month for high-speed equipment (rotating speed > ＞15000rpm).

3. Maintenance of transmission gear and rack

Applicable scene: large-scale equipment driven by rack (such as gantry engraving machine)

Maintenance steps:

Blow off the debris on the rack and pinion with compressed air every week, and then wipe the tooth surface with cotton cloth dipped in alcohol.

Check the gear meshing clearance (the standard value is 0.05-0.1mm) every month. If the clearance is too large, adjust the tensioner or replace the gear.

Apply gear oil (viscosity grade GL-4 85W/90) every six months, and pay attention to avoid oil dripping on the guide rail.

Second, the spindle and cooling system maintenance

1. Maintenance of spindle motor

Temperature monitoring:

When running, use infrared thermometer to detect the temperature of spindle housing (normally ≤45℃, and stop the machine for inspection if it exceeds 60℃). If the temperature rises too fast, it may be due to bearing wear or insufficient cooling.

Bearing replacement cycle:

Metal processing equipment needs to replace the spindle bearing every 2000 hours (NSK or SKF high-precision bearing is recommended), and nonmetallic equipment can be extended to 3000 hours.

When replacing, the spindle taper hole should be cleaned synchronously, and the radial runout (≤0.01mm) should be detected with a special inspection rod.

Dynamic balance calibration:

Dynamic balance should be done after each tool change (dynamic balance instrument can be used), and imbalance will lead to increased spindle vibration (it must be calibrated when the amplitude is greater than ＞0.05mm).

2. Maintenance of cooling system

Water cooling system (spindle cooling):

Change the cooling water every week (deionized water or special coolant is recommended) to avoid using tap water to prevent scaling.

Check the water pump flow (standard ≥5L/min) every month, and check the water pressure (0.1-0.2MPa) with a pressure gauge. If the flow is insufficient, clean the pipeline or replace the water pump.

Clean the inner wall of water tank and filter every quarter to remove scale and impurities (it can be soaked in citric acid solution for 1 hour).

Oil cooling system (servo motor cooling):

Replace the hydraulic oil of the oil cooler every six months (ISO VG46 hydraulic oil is recommended), and clean the dust on the radiator of the oil cooler.

Three, electrical and control system maintenance

1. Servo motor and driver maintenance

Cleaning requirements:

Use compressed air (pressure ≤0.4MPa) to blow off the dust from the cooling holes of the motor encoder and driver every month to avoid overheating alarm caused by dust accumulation.

Insulation detection:

Measure the insulation resistance of motor winding (≥5MΩ) with a megger every year. If it is lower than 1MΩ, dry or replace the motor.

Encoder calibration:

When the position deviation of the equipment occurs (such as the machining dimension continuously exceeds the tolerance), it is necessary to re-calibrate the encoder zero point with special software (such as Lei Sai servo debugging software).

2. CNC system and circuit maintenance

System backup:

Back up CNC system parameters (such as pitch compensation and reverse clearance parameters) every week, and store them in U disk or cloud to prevent data loss caused by system failure.

Line inspection:

Open the electrical box every quarter, check whether the terminals are loose (mainly servo motor power line and encoder line), and use multimeter to detect the terminal voltage (DC24V 10%).

Aging cables (such as damaged sheath and exposed core) need to be replaced immediately. It is recommended to use shielded cables to reduce electromagnetic interference.

Heat dissipation of electric box:

Clean the filter screen of the fan in the electric box every month, and replace the fan every six months (to ensure that the wind speed is ≥2m/s) to avoid PLC crash caused by high temperature.

Four, tool and tool magazine maintenance (with tool magazine equipment)

1. Tool management

Storage requirements:

The tool should be stored in a constant temperature drying cabinet (temperature 20 5℃, humidity ≤50%), and the taper surface of the handle should be coated with antirust oil to avoid accuracy failure caused by bumping.

Wear detection:

After every 50 workpieces are processed, the tool presetting instrument is used to detect the wear of the cutting edge (if the flank wear of the metal tool is more than ＞0.3mm, it needs to be replaced; if the non-metal tool is more than 1 mm).

Dynamic balance management:

Tools with a diameter of > ＞10mm must be dynamically balanced (residual unbalance ≤G2.5), and high-speed machining (> ＞20000rpm) requires the use of hydraulic tool holders or heat-shrinkable tool holders.

2. Maintenance of tool magazine and tool changing mechanism

Tool magazine cleaning:

Clean the debris on the tool sleeve of the tool magazine with a brush every week, and check whether the positioning pin of the tool sleeve is loose (the positioning error is ≤0.02mm).

Tool change accuracy calibration:

Check the repeated positioning accuracy of tool changing (≤0.01mm) with the calibration table every month, and adjust the tightness of tool magazine positioning sensor or mechanical gripper when it is out of tolerance.

Lubrication points:

Apply dry grease (such as molybdenum disulfide grease) to the transmission gear of the tool magazine every quarter to avoid oil pollution to the tools.

Five, the whole machine precision calibration and performance test

1. Regular precision testing

Check the standard value cycle of project tools

Table flatness Marble level+feeler gauge ≤0.03mm/1000mm every quarter.

X/Y/Z axis linearity laser interferometer ≤0.02mm/1000mm every six months.

Triaxial verticality square+dial indicator ≤0.02mm/300mm every six months.

Repetitive positioning accuracy of laser interferometer ≤±0.005mm per month.

2. Performance test method

Idle running test: let the equipment run idle for 30 minutes at the highest speed of 70% every week, and check whether each axis runs smoothly and whether there is abnormal noise (≤75dB).

Cutting test: Machining test pieces with standard parts (such as aluminum alloy squares) every month to detect dimensional accuracy and surface roughness (Ra≤1.6μm for metal parts).

Emergency stop response: test the response time of emergency stop button (≤0.5 second) every quarter to ensure the safety protection function is effective.

Six, maintenance records and fault warning

1. Establish a maintenance ledger

Records include: maintenance date, items, consumables used, test data (such as spindle temperature and guide rail clearance) and operator's signature, which is convenient for tracing back the problem.

It is recommended to use spreadsheets or equipment management software (such as EAM system) to automatically remind maintenance intervals.

2. Early warning signals of common faults

Mechanical abnormality: abnormal sound of guide rail (possible lack of oil or wear), screw sticking (insufficient lubrication or debris blockage).

Electrical anomalies: driver alarm (overcurrent, overheating), system crash (unstable voltage or poor line contact).

Abnormal precision: the dimensions of three consecutive workpieces are out of tolerance (the screw pitch needs to be calibrated for compensation), and vibration lines appear on the surface (the spindle dynamic balance fails).

VII. Environment and Safety Management

Workshop environment requirements:

The temperature is 15-30℃ and the humidity is 40%-70%. Keep away from direct sunlight and vibration sources such as stamping equipment (vibration acceleration ≤0.5g).