1. Radial sliding flap (horizontal flap)

Principle: The valve blocks of the mold slide and open along a circular radial (horizontal) direction, driven by mechanisms such as guide grooves, guide rails, or diagonal pins.

For example, a slanted guide groove is set on the outer side of the valve block, which is guided by a slanted pin fixed on the mold. When opening the mold, the slanted pin drives the valve block to slide radially outward, achieving demolding.

Features:

Simple structure: suitable for small and medium-sized molds, with low processing costs.

Applicable scenarios: Commonly used for circular products with no complex concave convex structures on the surface, such as bottle caps, flanges, etc.

Limitations: The sliding space of the valve block is limited, making it difficult to handle products with large depths or complex inner walls.

2. Axial lifting flap (vertical flap)

Principle: The valve block moves up and down along the circular axis (vertical direction) to achieve opening and closing, usually driven by hydraulic, pneumatic, or cam mechanisms.

For example, a lifting platform is installed at the bottom of the mold, which drives the petals to descend vertically during mold opening, separating the product from the petals.

Features:

Small footprint: No need for radial sliding space, suitable for scenarios where mold installation space is limited.

Applicable scenarios: Suitable for high cylindrical and deep cavity circular products, such as cups, pipes, etc., especially suitable for situations where radial strain of products needs to be avoided.

Limitations: High precision and stability requirements are placed on the lifting mechanism, and complex products may require the use of other demolding methods.

3. Rotating flap (hinged flap)

Principle: The petal block is connected to the mold body through hinges or shafts. When opening the mold, the petal block rotates around a fixed axis to open, similar to "petal unfolding".

For example, one end of the petal block is hinged on the mold base, and the other end is linked through a connecting rod or gear mechanism to synchronously rotate and unfold during mold opening.

Features:

Smooth demolding: Rotating motion can reduce the impact on the product, suitable for thin-walled or easily deformed circular products (such as plastic containers, precision parts).

Applicable scenarios: Suitable for complex molds with multiple valve combinations, such as circular products with side concave, threaded, or multi segment shapes.

Limitations: The hinge structure is prone to wear and requires regular maintenance, and the mold design and processing are difficult.