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Maintenance and Operation of Jaw Crushers

The jaw crusher (referred to as "jaw crusher" for short) is a core crushing equipment in industries such as mining, construction, and building materials. Its stable operation relies on scientific operation specifications and regular maintenance. The following details the key points of its maintenance and operation from four dimensions—"correct operation methods", "daily/regular maintenance points", "common fault diagnosis and troubleshooting", and "safety operation specifications"—to help extend the equipment service life and reduce failure rates.

I. Correct Operation Methods of Jaw Crushers

Proper operation is the foundation for reducing equipment wear. Focus on three links: "pre-startup inspection", "in-operation monitoring", and "post-shutdown handling".

1. Pre-Startup: Comprehensive Inspection to Eliminate Hidden Risks

Before starting the machine, the key parts of the equipment must be inspected to avoid starting with faults:

• Lubrication System: Check the oil level in the lubricating oil tank (it should be between the oil gauge scales) and oil quality (no turbidity, no impurities, no emulsification). Ensure the lubricating pump and oil pipes are unobstructed, and the lubrication points (such as main shaft bearings and movable jaw bearings) are supplied with oil normally.

• Fastening Components: Check if the connecting bolts of the frame, movable jaw, and fixed jaw (e.g., jaw plate fixing bolts, bearing seat bolts) are loose. If loose, tighten them immediately (it is recommended to use a torque wrench to fasten according to the torque value specified in the equipment manual).

• Crushing Chamber Inspection: Remove residual ore and debris in the crushing chamber (to avoid "choking" when starting the machine). Check the wear condition of the jaw plates (fixed jaw plate and movable jaw plate); if the wear is severe, replace them to prevent scratching the equipment body. Ensure the liner fits closely with the jaw plate.

• Transmission System: Check the tension of the V-belts (the deflection should be approximately 15-20mm when pressing the belt by hand) and whether the pulleys are aligned (to avoid belt deviation and wear). Check if the elastic pads of the coupling are intact and if there is any potential for abnormal noise.

• Electrical System: Check if the power cables and control lines are damaged, if the motor wiring is secure, and if the overload protection and emergency stop button are functioning properly.

2. In-Operation: Standardized Feeding and Real-Time Monitoring

During equipment operation, control the feeding method and parameters, and monitor the operating status in real time:

• Feeding Specifications:

• Feed materials evenly and continuously. Avoid "one-sided feeding" (which causes uneven stress and eccentric wear of the jaw plate) or "overfeeding" (which leads to blockage of the crushing chamber and motor overload).

• The feed particle size must meet the equipment design requirements (the maximum particle size should not exceed 80%-85% of the inlet width of the crushing chamber). It is forbidden to mix hard objects such as metal blocks and steel bars (it is recommended to install an iron removal device at the feed port).

• Operation Monitoring:

• Listening: During normal operation, there should be a uniform "crushing sound". If there is a "metal impact sound" (possibly due to loose jaw plates or hard objects entering), "dull sound" (possibly due to blockage in the chamber), or "abnormal noise" (possibly due to bearing damage), stop the machine immediately for inspection.

• Observation: Observe whether the crushed product particle size is uniform (if the particle size becomes larger, it may be due to jaw plate wear or an increase in the discharge port). Monitor the bearing temperature (normal temperature ≤ 60℃; if it exceeds 70℃, stop the machine to check the lubrication or bearings).

• Control: It is forbidden to adjust the discharge port or clean the crushing chamber when the equipment is running. If "choking" occurs (motor overload and equipment shutdown), cut off the power immediately, remove the materials in the chamber, and then restart.

3. Post-Shutdown: Timely Cleaning and Status Recording

After shutdown, complete the finishing work to prepare for the next startup:

• Clean the residual materials and dust on the equipment surface and in the crushing chamber to prevent material caking or equipment corrosion.

• Check the wear degree of the jaw plates and liners, and record the wear condition (it is recommended to establish an equipment ledger and mark the replacement cycle).

• Turn off the lubrication system. If the equipment is out of service for a long time (more than 1 week), drain the lubricating oil in the oil tank and apply anti-rust oil to the exposed metal parts.

• Record the operation time, fault conditions, and maintenance content of this time to form an equipment operation file (facilitating problem tracing).

II. Maintenance Points of Jaw Crushers

Maintenance is divided into "daily maintenance", "regular maintenance", and "long-term shutdown maintenance", which must be carried out according to the cycle to avoid fault accumulation.

1. Daily Maintenance (Implemented Daily)

• Lubrication Inspection: Replenish lubricating oil (use the oil recommended in the equipment manual, such as 46# or 68# anti-wear hydraulic oil) and ensure no oil leakage or blockage at the lubrication points.

• Fastening Inspection: Focus on checking the jaw plate fixing bolts, bearing seat bolts, and frame connecting bolts. Tighten them immediately if loose (loose bolts may cause jaw plate displacement and equipment vibration).

• Cleaning Inspection: Clean the debris around the equipment to ensure good ventilation (to prevent poor heat dissipation of the motor).

2. Regular Maintenance (Implemented According to the Cycle, Refer to the Equipment Manual)

Adjust the maintenance cycle according to the equipment usage frequency (e.g., 8 hours of operation per day vs. 24 hours). The core maintenance items are as follows:

3. Long-Term Shutdown Maintenance (Shutdown for More Than 1 Month)

• Thoroughly clean the materials in the crushing chamber and hopper, and blow off the dust inside the equipment with compressed air.

• Dismantle rust-prone parts (such as jaw plates and liners), apply anti-rust oil, and store them separately (avoid humid environments).

• Cover the motor and electrical cabinet with dust covers, cut off the main power supply, and conduct power-on inspections of the electrical system regularly (every 2 weeks) to ensure normal operation.

• Check the anchor bolts of fixed parts such as the frame and base; tighten them if loose to prevent equipment inclination due to ground settlement.

III. Common Fault Diagnosis and Troubleshooting

Most common faults of jaw crushers are related to "insufficient lubrication", "improper feeding", and "part wear". Quick troubleshooting can reduce downtime.

IV. Safety Operation Specifications

Jaw crushers are heavy-duty equipment. Safety rules must be followed during operation to avoid personal injury:

1.Operators must receive professional training, be familiar with the equipment structure and operation process, and unqualified personnel are prohibited from operating.
2.Before starting the machine, confirm that there are no personnel around the equipment (especially near the crushing chamber and transmission parts), and sound the whistle for warning before starting.
3.When the equipment is running, it is forbidden to reach into the crushing chamber with hands or tools to clean materials. If cleaning is necessary, the machine must be stopped and the power supply must be cut off (hang a "No Switching On" warning sign).

4.During maintenance operations such as adjusting the discharge port or replacing the jaw plate, use a jack or bracket to fix the movable jaw (to prevent the movable jaw from falling), and prohibit overhead operations.

5.If the equipment malfunctions, stop the machine immediately and report it. It is forbidden to disassemble key parts (such as bearing seats and main shafts) without authorization; professional maintenance personnel must handle it.

6.Operators must wear personal protective equipment (safety helmet, dust mask, anti-smashing shoes, goggles) to avoid dust inhalation or material splashing injury.

Summary

The core of jaw crusher maintenance and operation is "prevention first"—reduce abnormal wear through standardized feeding, eliminate hidden risks in advance through regular maintenance, and avoid accidents through safe operation. It is recommended to formulate a personalized maintenance plan based on the equipment manual (parameters and maintenance cycles may vary for different manufacturer models) and establish an equipment ledger to record operation and maintenance data, thereby maximizing the equipment service life and reducing comprehensive operating costs.