Learning from Failures: On-site Treatment and Root Cause Analysis of the Ten Common Operational Problems of Brick Making Machines

Learning from Failures: On-site Treatment and Root Cause Analysis of the Ten Common Operational Problems of Brick Making Machines

The operation of a brick making machine is a constant battle with wear, vibration, and pressure. Failures are inevitable, but each one is a distress signal from the equipment and a valuable learning opportunity. Mastering the method from on-site treatment to root cause analysis is the key to transitioning from reactive maintenance to proactive maintenance. The following is an in-depth analysis of the ten common operational problems.

Problem 1: Loose Bricks and Insufficient Strength

On-site Treatment: Immediately check whether the hydraulic system pressure indicator reaches the set value; listen for a dull and weak vibration sound; and inspect the raw materials to see if they are difficult to form into a ball after being squeezed.

Root Cause Analysis:

Insufficient Pressure: Internal leakage in the hydraulic pump, low pressure setting of the relief valve or a stuck valve core, or damaged cylinder seals can lead to pressure leaks.

Insufficient Vibration Force: Damaged vibration motor bearings, improperly adjusted eccentric blocks, or loose screws can reduce the excitation force; a missing power phase can lead to insufficient motor speed.

Raw Material Issues: Imbalanced water-cement ratio (too much or too little water), insufficient cement content, or improper aggregate grading. Problem 2: Uneven brick thickness, chipped corners, and broken edges.

On-site intervention: Stop the machine and observe whether the material distribution vehicle is moving and discharging evenly; check whether the pallet is flat; and remove any hard material remaining on the mold walls.

Root cause analysis:

Uneven material distribution: Deformation of the distribution vehicle track, wear of the plow blade, or arching of material in the hopper results in uneven fill levels in the mold cavities.

Pad deformation: Poor pallet quality or long-term uneven load bending results in uneven mold cavity height.

Mold problem: Adhesion or wear to the mold wall, or excessive play on the ram guide rods, causes material to be squeezed to one side during pressing.

Problem 3: Hydraulic system noise and excessive oil temperature.

On-site intervention: Listen to the source of the noise (pump, valve, or motor); check the hydraulic oil tank temperature; and check whether the cooling water or fan are functioning properly.

Root cause analysis:

Pump cavitation: Clogged oil filter, leaking oil inlet pipe, or low oil level can cause pump cavitation noise.

Component damage: Internal wear in the hydraulic pump, bearing damage, or high-frequency oscillation of the valve core. System overheating: Cooler blockage, severe system leakage (energy converted into heat), improper oil viscosity, or prolonged overload operation.

Problem 4: Slow, creeping, or weak cylinder movement

On-site intervention: Observe the operation of a single cylinder or multiple cylinders; check the oil level and oil quality.

Root cause analysis:

System air intake: Poor seals in the oil suction line allow air to enter the system, resulting in jerky movement and creeping.

Oil line blockage: A clogged oil filter or undersized valve leads to insufficient flow and slow movement.

Internal leakage: Worn cylinder seals or internal leakage in the control valve cause pressure and flow loss, manifesting as weakness.

Problem 5: The vibrating table is noisy and banging.

On-site intervention: Immediate emergency shutdown! Use a hammer to check all bolts connecting the vibrating motor, vibrating table, and frame for looseness.

Root cause analysis:

Loose fasteners: This is the most common and dangerous cause. Equipment subjected to prolonged high-frequency vibration can easily loosen or shear bolts. Component damage: Damaged vibration motor bearing, broken eccentric block, or broken buffer spring/rubber pad.

Problem 6: Difficult demolding, damaged bricks

On-site solution: Check the mold inner wall and the pressing head for smoothness and scratches; apply grease to the mold guide pins; fine-tune the synchronization of the demolding ejector pins.

Root cause analysis:

Mold problem: Poor mold finish, back taper (wear), or lack of release agent (lubrication).

Operational problem: Overfilling or excessive pressure causes bricks to expand excessively and become stuck in the mold.

Ejection asynchrony: Multiple demolding ejector pins raise and lower asynchronously, causing bricks to tear.

Problem 7: No PLC output, entire machine inoperative

On-site solution: Check the PLC indicators (power, run, error); check that the emergency stop button is reset; check the main power circuit breaker.

Root cause analysis:

Power failure: Blown control circuit fuse, damaged power module.

Safety circuit disconnection: Protective devices such as the emergency stop button, safety door switch, and pressure relay have not reset. Hardware Failure: The PLC or output expansion module is damaged.

Problem 8: The solenoid valve is not operating or the coil is burned.

On-site Action: Use a multimeter to measure the coil resistance; manually force the output at that point in the electrical control cabinet and listen for a sound.

Root Cause Analysis:

Coil Problem: Voltage mismatch, frequent starts and stops leading to overheating, burnout, or quality defects.

Valve Spool Stuck: Oil contamination and impurities entering the valve spool clearance prevent the solenoid from moving the spool after power is applied.

Wiring Problem: Loose wiring or a damaged intermediate relay prevents the control signal from being delivered.

Problem 9: The silo is not unloading or the material distribution cart is malfunctioning.

On-site Action: Clear the silo of material accumulation; check the material distribution cart track for obstructions; and verify that the drive motor is functioning.

Root Cause Analysis:

Material accumulation: High moisture content of the raw material or prolonged retention in the silo creates a "rathole."

Mechanical Jam: Worn material distribution wheels, deformed tracks, or obstructions. Electrical Failure: Drive motor overload protection, limit switch failure, or inverter failure.

Problem 10: Extensive honeycombing on the brick surface.

On-site Action: Check whether the coarse aggregate particle size in the raw materials exceeds the standard; reduce the vibration frequency or duration; increase the slurry fluidity.

Root Cause Analysis:

Improper raw material ratio: Excessive coarse aggregate and insufficient fine aggregate (sand) prevent effective void filling; poor material workability and insufficient fluidity.

Improper vibration process: Excessive vibration causes aggregate to separate from the cement slurry, resulting in aggregate sinking and concentration.

Poor Venting: Air in the material cannot be effectively expelled before pressing, forming pores on the brick surface.

Conclusion: Troubleshooting is a temporary solution, while root cause analysis is a fundamental solution. By systematically recording the symptoms, solutions, and ultimate root causes of each fault, you will be able to create a "health map" for your equipment. This will not only enable faster problem resolution in the future, but also help you establish a predictive maintenance system to prevent faults from occurring, ultimately ensuring long-term production line operation.