How to operate a self-loading concrete mixer and what safety regulations need to be observed

The core operations of the self-feeding mixer truck can be summarized as: starting preheating→ feeding and batching→ mixing → transportation→ discharge→ cleaning; The safety red line is to prevent tipping, roll clamping, electric shock, solidification, and falls from heights. Below is a step-by-step explanation.

1. Standard Operating Procedures (Six Steps)

1. Pre-startup inspection and preheating

Environment and vehicles: Park on a solid, flat ground, pull the handbrake, and use triangular wood wheel pads; Check the exterior, tires, lights, horn, brakes, and hydraulic pipelines for leaks.

Control reset to zero: The stirring drum handle is stopped, and the feeding arm/bucket is retracted and locked.

Engine start: idle mode, stirring drum idle at low speed for 10 minutes, hydraulic oil temperature ≥ 20°C before operation.

Barrel cleaning: Before feeding, reverse the mixing drum to drain accumulated water and debris.

2. Automatic feeding and batching

Alignment: The vehicle faces the material pile at a moderate distance, with a solid ground.

Bucket operation (hydraulic handle):

Forward thrust: lowering the arm downward; Rear pull: arm pull upward

Left push: Load buckets to unload; Right pull: Collect the bucket and scoop up the material

Batching sequence: sand→ gravel→ cement, weigh according to the proportions; After the hopper is lifted into position, it is tilted and unloaded into the drum.

Automatic water filling: connect the water source, start the pump, and add water precisely according to the ratio (typically 30–40 seconds). After filling, the handle returns to normal.

3. Mixing operations

Start stirring: Close the stirring switch, stir forward, speed 3–8 rpm; Stir for 90–140 seconds until evenly mixed.

Process monitoring: Monitor current, oil temperature, and material status inside the cylinder; strictly avoid overloading.

4. Transportation and driving

Stirring Hold: Maintain forward rotation at 2–3 rpm during transport to prevent segregation and solidification.

Speed limits: ≤ 5 km/h in factory areas, 40 km/h ≤ on highways; Sudden braking and sharp turns are strictly prohibited (a high center of gravity can cause rollover).

Height/Slope: Pay attention to height limits (generally ≥ 3.8m); climbing ≤ 15°, engine braking is required for downhill use, and coasting in neutral is prohibited.

Safety lock: The feeding arm / bucket is fully retracted and locked to prevent swinging and injury.

5. Unloading operations

Alignment: The rear of the car aligns with the hopper/pouring point, ensuring the ground is flat and solid.

Unloading operation:

The tank body tilts forward by 30°–45°

Low-speed forward rotation unloading, idle control, and no sudden acceleration

When using the extended groove, keep your hand stuck in the groove gap; fold and lock it after use

6. Cleaning and Finishing

Timely cleaning: After unloading, immediately add water and rapidly clean the cylinder, blades, hopper, and discharge chute to prevent concrete solidification.

Drainage: After cleaning, reverse the wastewater to drain thoroughly. In winter, thoroughly empty the water tank, pipes, and cylinder to prevent freezing and cracking.

Shutdown: Idle for 3–5 minutes to cool down, turn off the engine, cut off power, pull the handbrake, lock the car.

2. Core Safety Regulations (Must Be Followed)

1. Personnel safety

Certified Employment: Professional training and licensed operation; Strictly prohibit working without a license, under the influence of alcohol, or while working while fatigued.

Protective attire: safety helmets, non-slip shoes, goggles, dust masks.

No entry into the danger zone: No one is allowed to stand within 3 meters of operation; crossing, drilling the truck, or staying under the hopper/arm is prohibited.

Boarding and alighting: Use special ladders/handrails, three-point contact, no jumping out; Pedals and handrails should be free of oil stains and no icing.

2. Anti-rollover (top priority)

Floor: Must be solid and level; soft ground should be covered with steel plates or sleepers; It is forbidden to work or park on slopes, potholes, or soft surfaces.

Driving: Sudden turns and sudden braking on highways are strictly prohibited; When heavily loaded, slow down and drive slowly, with sufficient turning radius.

Hoisting: When lifting the feeding arm, the vehicle must be level; tilting is prohibited to prevent center of gravity shift and tipping.

3. Mechanical and operational safety

Maintenance, lubrication, and cleaning are prohibited during operation; Inside the cylinder operation must be: turn off the engine→ remove the key→ hang a "Staff Operating" sign→ and use double U-shaped clips to lock the cylinder (to prevent rotation).

Hydraulic system: Overpressure is prohibited; if a pipeline ruptures, immediately turn off the flame to release pressure and then handle it.

Electrical: Waterproof, moisture-proof, reliable leakage protection; Do not operate the switch with wet hands.

Emergency shutdown: If abnormal noises, odors, leakage, material jamming, or loss of control occur, immediately turn off the engine and cut off power.

4. Concrete quality and equipment protection

Time limit: ≥ 30°C, 2 hours from discharge to pouring ≤ 2 hours; Low temperature ≤ 2.5 hours; do not use after the time limit.

Do not dry spin or stop for long periods: Maintain low speed during transport or waiting to prevent segregation and solidification.

Pump protection: No idling, continuous operation ≤ 15 minutes; Drain thoroughly in winter to prevent frost.

5. Fire prevention and emergency response

Come with a **≥2kg dry powder fire extinguisher ** and place it in an easily accessible location.

Fuel/hydraulic oil leaks: Immediately turn off the flame, prohibit open flames, ventilate, and clean up any leaks.

Fire: Use a fire extinguisher → alarm → power outage; Do not use water to extinguish electrical or oil-related flames.

3. Common Taboos (Ten Restrictions / Ten Prohibitions)

Operation without licenses, under the influence of alcohol, or while fatigued is prohibited.

Do not work or park on slopes, soft ground, or potholes.

Do not brake suddenly, make sharp turns, or drive at high speeds.

Do not stand, cross, or drill under the hopper/arm.

Maintenance, cleaning, or lubrication during operation is prohibited.

No work inside the cylinder is allowed, without locking the cylinder body or hanging a sign.

Do not use concrete beyond the time limit (over 2–2.5 hours).

Do not dry or stop the mixing drum for long periods (to prevent segregation and solidification).

Do not drain in winter (to prevent frost cracking).

Do not overload, overpressure, or improperly operate hydraulic/electrical systems.

4. Shorthand Mnemonics

First, check, second, warm, third, add ingredients; fourth, stir, fifth, transport, sixth, wash; Stable vehicles on flat ground to prevent rollovers, certified protection against entry; No emergency, no deviation, no dry stop; concrete that has expired cannot be used; Turn off the fire lock cylinder and inspect it again to prevent fire and electrical safety.