working principle of precast concrete slab machine

Precast concrete slab machine is a kind of equipment specially used for producing precast floor, which is usually used for large-scale industrialized construction production. Its working principle involves key links such as concrete molding, steel bar arrangement, vibration compaction and curing demoulding. The following is the specific working principle:

1. Material preparation

Mix cement, sand, gravel, water and other additives according to the designed proportion to make a uniform concrete mixture.

2. Mold arrangement and preparation

The production of floor can be carried out in horizontal molds or vertical molds.
The position of expansion joints, holes or cable troughs will be pre-set on the mold (such as hollow floor requires core mold or inflation pipe).
Rebar arrangement: Pre-place steel mesh or steel skeleton in the mold to enhance the bending and tensile strength of the floor.

3. Concrete filling and molding

Feeding: The concrete mixture is evenly delivered to the mold through automatic feeding equipment.
Compacting: Depending on the machine model, the equipment uses the following methods to compact the concrete:
Vibration compaction: The mold is vibrated by a high-frequency vibrator to make the concrete fully fill the mold gap and be dense and free of bubbles.
Extrusion molding: The concrete is pressed by the extrusion system to force it to form, which is suitable for the production of large-span prestressed slabs.
Rolling molding: The concrete is rolled and compacted using rolling equipment.

4. Prestressing technology (if applicable)

For Precast slabs, the equipment applies tension to the Precast steel bars before the concrete is filled. After molding, the prestress of the steel bars will enhance the bending resistance of the slab when the concrete is cured.

5. Curing and demoulding

Curing and curing: The formed concrete slab is sent to the curing room, and steam curing or natural curing is used to accelerate the hardening of the concrete. The curing time is usually 12-24 hours.
Demolding: After the slab reaches a certain strength, it is removed from the mold using an automatic demoulding device.

6. Post-processing

Cutting: Some equipment is equipped with a cutting device to cut the slab into specified sizes.
Surface treatment: Surface polishing, patching or spraying can be performed to improve the appearance quality of the floor.
Stacking and transportation: The finished floor is ready to be sent to the construction site after being stacked.
Summary of key technologies and working principles
Mechanized feeding and forming: Improve production efficiency and plate quality.
Vibration or extrusion technology: Ensure the compactness of concrete and avoid internal defects.
Precast steel bar technology: Improve the bearing capacity and is suitable for large-span floor slabs.
Rapid curing and automatic demoulding: Ensure continuous operation of the production line.
Common types of floor slab machines
Hollow floor slab machine: Uses core molds or tubular core materials, leaving hollow parts during the molding process to reduce weight.
Precast concrete slab machine: Uses Precast steel bar technology, suitable for floor slabs with larger spans.
Composite floor slab machine: Can produce composite floor slabs with insulation layer or additional functions.