The steel casing also provides the mechanical interface between the magnetic unit and the formwork. Depending on the design, shuttering magnets can secure formwork directly through the casing or work together with adapters and brackets for different formwork profiles.
The holding force of shuttering magnets is typically specified as the maximum pull force measured perpendicular to a clean, sufficiently thick steel plate under controlled conditions. These ratings provide a useful reference for comparing different shuttering magnets, but they should not be treated as the actual load capacity of complete formwork systems.
In practical use, the available holding force can be reduced by air gaps, concrete residue, surface coatings, rust, uneven contact surfaces, or insufficient steel thickness. Because magnetic attraction decreases rapidly as the gap increases, keeping the working surfaces clean and maintaining good contact with the casting table are particularly important.
The required holding force depends on formwork height, profile geometry, concrete pressure, vibration, magnet spacing, and the way shuttering magnets are connected to the formwork. Higher rated pull force is not always necessary; shuttering magnets should be selected as part of the complete fixing arrangement rather than by pull force alone.
Before positioning shuttering magnets, the steel casting table and the magnetic working surfaces should be kept clean and free from concrete residue or other debris. The magnets are then positioned according to the formwork layout and connected to the side forms directly or through suitable adapters.
Pressing the operating button engages the magnetic unit with the casting table and secures the formwork in position. After casting and demoulding, a release tool is used to lift the magnetic unit and reduce the holding force. Shuttering magnets can then be removed or repositioned for the next production cycle.
Shuttering magnets should not be released by striking the casing or operating button with hammers or other hard tools, as repeated impact may damage the mechanism, casing, or internal magnetic assembly.
The working surfaces of shuttering magnets should be kept clean to minimize air gaps and maintain consistent magnetic contact with the steel casting table. Hardened concrete residue, rust, and surface damage can reduce the available holding force.
The casing, operating mechanism, and magnetic unit should also be checked periodically for deformation, wear, or impact damage. For shuttering magnets used frequently in production, pull force testing can help identify performance loss before it affects formwork positioning.
