Daily maintenance of ceramic hot press sintering furnace

The daily maintenance of ceramic hot press sintering furnace needs to start from the five core modules of furnace structure, heating system, atmosphere control, safety protection, and operating standards, combined with preventive maintenance and data-driven management, to extend equipment life and ensure sintering quality. The following are specific maintenance points:

1. Furnace structure maintenance: prevent thermal stress damage
Sealing inspection of furnace body
Daily inspection: Apply soapy water to the furnace door, observation window, gas interface, and other areas to observe for the formation of bubbles.
Sealing strip replacement: Replace the furnace door sealing strip (made of fluororubber material) every 50 sintering cycles to ensure a smooth and deformation free sealing surface.
Furnace deformation monitoring: Use a laser rangefinder to measure the verticality of the four corners of the furnace every quarter to prevent sealing failure caused by creep of the furnace at high temperatures.
Maintenance of insulation layer
Surface cleaning: Use a vacuum cleaner to clean the dust on the surface of the insulation layer every week to prevent impurities from carbonizing and corroding the insulation material at high temperatures.
Damage repair: If the insulation layer cracks or falls off, fill it with ceramic fiber cotton of the same material and fix it with high-temperature adhesive (temperature resistance ≥ 1800 ℃).

2. Heating system maintenance: ensure temperature uniformity
Heating element inspection
Graphite heating rod: Check the surface oxidation condition with an endoscope every month, and replace it when the oxide layer thickness is ≥ 0.5 mm; Use an infrared thermometer to detect temperature deviations in each area, with a tolerance of ≤± 5 ℃.
Molybdenum wire heating element: Check the molybdenum wire for brittle fracture every quarter, and replace it if the fracture length exceeds 10% of the total length; Before powering on, introduce nitrogen protection (flow rate ≥ 5 L/min) to prevent oxidation.
Thermocouple calibration
Periodic calibration: Every 3 months, calibrate the thermocouple with a standard temperature source (accuracy level 0.1) to ensure that the measured value has an error of ≤± 2 ℃ compared to the actual value.
Fixed position: Check the insertion depth of the thermocouple after each mold installation (50 ± 2 mm from the furnace bottom) to avoid measurement distortion caused by contact with the mold or furnace wall.

3. Atmosphere control system maintenance: avoid material oxidation/reduction
Gas pipeline maintenance
Leakage detection: Use a helium mass spectrometer to detect gas pipeline connections every month, with a leakage rate of ≤ 1 × 10 ⁻⁶ Pa · m ³/s.
Filter cleaning: Remove the gas filter every quarter and use an ultrasonic cleaning machine to remove impurities (frequency 40 kHz, time 15 minutes) to prevent clogging and affect flow accuracy.
Atmosphere purity control
Gas replacement: Before each sintering, perform a three-stage cycle of “vacuuming → filling with nitrogen gas (purity ≥ 99.999%) → vacuuming again” for 3 cycles to ensure that the oxygen concentration in the furnace is ≤ 1 ppm.
Dew point monitoring: Install a dew point meter (range -80 ℃ to 20 ℃) in the hydrogen usage area to monitor the gas dew point in real time and prevent material hydrolysis caused by water vapor.

4. Maintenance of safety protection system: prevention of explosion and poisoning
Hydrogen safety device
Concentration alarm: Install a hydrogen sensor (range 0-4% vol, response time ≤ 3 seconds) in the hydrogen usage area, automatically cut off the gas source and start exhaust when exceeded.
Flame arrester inspection: Remove the flame arrester from the hydrogen pipeline every six months and blow it with compressed air (pressure 0.3 MPa) to ensure no carbon buildup or blockage.
Mechanical safety device
Pressure protection: The hydraulic system is equipped with an overpressure alarm device (set pressure to 1.1 times the rated pressure), which automatically releases pressure when overpressure occurs.
Mold fixing: Adopting a dual safety structure of “bolt pre tightening+hydraulic locking”, check the bolt torque (≥ 50 N · m) after each mold installation to prevent the mold from loosening and flying out under high pressure.

5. Operational standards and data management
Operation Training
New employee assessment: Operators must pass a dual assessment of “theoretical examination+practical exercise” (theoretical score ≥ 80 points, practical score ≥ 90 points) before they can independently operate equipment.
Regular refresher training: Organize safety operation refresher training every six months, focusing on updating equipment failure cases and emergency response procedures.
Maintain record management
Electronic archives: Establish an equipment maintenance database to record the time, content, replacement part model, and repair results of each maintenance, supporting multi-dimensional queries by time, part type, and other dimensions.
Trend analysis: By using data analysis software to statistically analyze thermocouple calibration data, heating element replacement cycles, etc., predict equipment failure risks, and develop maintenance plans in advance.