Basic Process for Small-Scale Concrete Mixing Operations

Basic Process for Small-Scale Concrete Mixing Operations

For small-scale concrete mixing operations, whether for patio paving or home repairs, following a clear and safe basic process is crucial. This not only ensures the concrete is of uniform quality and meets performance standards, but also guarantees a safe and efficient operation. The entire process can be logically divided into three main stages: preparation, mixing, and finishing.

Stage One: Thorough Preparation Before Operation. This is the foundation of safety and success. First, choose a flat, solid site near the materials and construction area to place the mixer, ensuring it is stable and does not wobble. Check that all parts of the equipment are in good condition, especially that the mixing blades are securely installed, and lubricate the necessary parts as required. Next, prepare the dry aggregates (sand and gravel) and cement near the mixer according to the pre-calculated mix ratio (e.g., how many buckets of sand and gravel per bag of cement), ensuring the cement is stored in a moisture-proof environment. Also, prepare a sufficient supply of clean water. Operators must wear protective equipment such as work gloves, dust masks, safety glasses, and non-slip shoes.

Stage Two: Feeding, Mixing, and Discharging. This is the core of the process, and the key is controlling the feeding order and mixing time. Start the mixer and let it run for a short time to ensure it is operating correctly before adding materials. A "wet first, then dry" method is recommended to reduce dust and improve uniformity: first add most of the mixing water to the mixing drum, then add all the sand and cement, mix for about 1 minute to form a mortar, and finally add the gravel and the remaining water, continuing to mix. The total mixing time, starting from when all materials are added, generally takes 2-3 minutes, until the mixture is uniformly colored and there are no dry clumps or cement lumps. During mixing, it is strictly forbidden to put hands, tools, or any objects into the rotating mixing drum. After mixing is complete, place the wheelbarrow or hopper under the discharge port and smoothly discharge the concrete using the handle or switch.

Stage Three: Cleaning and Equipment Maintenance After Operation. After discharging, the concrete should be used as soon as possible to avoid premature setting if left in the mixer or wheelbarrow for extended periods. Next, add an appropriate amount of clean water and a few handfuls of pebbles to the mixing drum. Start the machine and let it run empty for 3-5 minutes for cleaning. The rotating blades and the friction of the pebbles will scrub away any remaining material adhering to the drum walls and blades. Then, drain the dirty water. This process may need to be repeated once or twice. Finally, thoroughly rinse the inside and outside of the mixing drum, the discharge chute, and the equipment surface with a high-pressure water gun or hose to ensure no residue remains. Clean the work area and return all tools to their proper places. A proper cleanup not only extends the equipment's lifespan but also provides safe and convenient conditions for the next operation.