A cement mixer truck keeps concrete in a liquid state through continuous rotation of its drum until it's delivered to the construction site.
Here's a breakdown of how it works:
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Drum Rotation: The primary mechanism is the rotating drum. This constant movement prevents the cement from settling and hardening.
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Internal Blades (Spiral): The inside of the drum is fitted with a spiral blade. This blade serves two critical functions:
- Mixing: As the drum rotates in one direction, the spiral blades lift and mix the concrete ingredients (cement, water, aggregates) thoroughly.
- Discharging: When the drum rotates in the opposite direction, the spiral blade pushes the mixed concrete towards the rear of the truck for discharge.
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Agitation During Transport: The drum continues to rotate slowly during transport. This constant agitation ensures the concrete remains workable and doesn't segregate (separate into its constituent materials).
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Hydraulic System: A powerful hydraulic system typically powers the drum's rotation, allowing for precise control of the mixing and discharging process.
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Water Tank: Many cement mixer trucks carry a water tank to add water to the mix as needed to achieve the desired consistency or to clean the drum after use.
In summary, a cement mixer truck utilizes a rotating drum with internal spiral blades and a hydraulic system to mix, agitate, and discharge concrete, maintaining its quality until delivery.
