One, Why do fireproof board panels crack?
1、Material-related issues
Framework Materials: Framework materials include studs and other accessories. If the quality of the framework materials does not meet the requirements, it will directly affect the overall stability of the framework, and is a major cause of plate seams, cracking, and deformation.
Panel Quality: As a facing material, the fire-resistant board is fixed tightly to the lightweight steel frame using high-strength self-tapping screws. If the board does not meet the quality requirements, the board and the frame cannot be securely fastened. When subjected to external forces, shear forces will occur at the board joints, leading to cracking.
Joint Filling Materials: Joint filling putty must possess excellent strength, adhesion, and flexibility, as well as good workability. If these properties are not met, cracks are unavoidable.
2、Reasons for Construction
Improper construction practices, such as deviating from design specifications and operating procedures, including:* Insufficient spacing between boards at joints* Uneven laying of large areas* Shorter or sparsely distributed fasteners* Insufficient or overly soft application of joint filler putty* Improper application of profiles for butt joints, interior corners, and exterior cornerswill all reduce the overall rigidity and strength of the frame, create internal stresses, and potentially lead to cracking at the joints.
3、Human factors
Under the influence of the pursuit of maximum profit, the construction contractor unilaterally lowered the quality requirements, manipulated construction materials, and engaged in practices such as "filling in the gaps with inferior materials," "thin layers for thicker coverage," and "using substandard materials to replace genuine ones."
4、Environmental Impact
Construction is typically performed in natural conditions, but indoor and outdoor temperatures and humidity levels are not constant throughout the year. In particular, the effects of indoor air conditioning and heating can reduce indoor humidity, which significantly alters the environmental conditions compared to the initial construction conditions. This can disrupt the original moisture balance in the magnesium board, causing shrinkage and cracking.
Two. How to repair fire-resistant board cracking
1、The resin has not fully cured; the molecules are too small, and the unqualified resin should be discontinued.
2. If the resin does not fully cure, appropriately increase the hot pressing temperature or extend the hot pressing time.
3、Excessive adhesive content in the surface adhesive film causes cracking in the fireproof board. Control the adhesive content of the surface adhesive film.