As the starting link of the production process, the mold design plays a huge role in the entire construction process of the prefabricated building. It not only needs to connect the upstream in-depth design but also plays a leading role in the entire component production process. If the design is unreasonable, there will be design defects. , then it will cause problems with PC components, concrete components cannot be assembled and used, resulting in direct economic losses, so the quality of the mold is directly related to the quality of the product, and the mold is designed to meet the requirements can be mass-produced components to ensure the accuracy and consistency of components It can also greatly shorten the manufacturing time and improve the production efficiency.
Since prefabricated buildings are just emerging, all links are in the research and exploration stage, and the design of prefabricated building molds has not received enough attention and attention, resulting in mold design There is no unified design standard in the industry, whether it is mold design, material selection, manufacturing There is no unified template mode for process and demoulding method, and the design and production method is relatively rough, and there are many deficiencies. How to innovate the tradition, move towards the modern production mode, and establish the development ideas and routes of prefabricated building molds that meet the market conditions under the premise of the current industry development are the primary issues in the development of molds at present.
1.Mold Design Guidelines
Combined with the current production situation of prefabricated building components production workshop and the design standards of other mature mold design industries in China, the mold design of prefabricated building components should follow the following principles to ensure practicability of the designed molds.
1) Facilitate the demoulding of components. PC components are concrete components with large mass and volume, which are inconvenient for transportation. Therefore, whether the mold release is convenient is the primary consideration in the mold design process. Demoulding will also increase the difficulty of on-site demoulding, and will also lead to damage to components during the demoulding process, greatly reducing production efficiency, resulting in a lot of waste of labor and material costs, and it needs to be increased in the design process where it is not easy to demold. Draft angle.
2) Mold dimensional accuracy. The dimensional accuracy includes two aspects, the dimensional accuracy of the components and the dimensional accuracy of the mold. The dimensional accuracy of the mold directly determines the accuracy of the components produced. The designer must ensure the dimensional accuracy of the mold and the dimensional accuracy of the components produced by the mold. The concrete poured in the middle will expand after solidification, so it should be taken into account at the beginning of the mold design, and a margin should be left in the design process, so as to ensure that the size of the components made by the mold will not be too large. within the tolerance range. During the welding process of the mold, the material and welding process used will also affect the dimensional accuracy.
3) Mold strength. After the concrete in the mold is solidified, the size will expand, and the side mold of the mold will be squeezed. If the mold strength is not enough, the mold will be deformed, and each set of molds is used for the production of multiple components. The dimensional error will gradually accumulate beyond the allowable tolerance range. There are many ways to ensure the strength of the mold, such as increasing the number of reinforcing ribs in the side mold, adding rods, and profiles as supports, etc.
4) The processing of the mold rib method. The design of the molded rib is mainly the size and form of the opening of the steel bar. If the size of the opening in the design is large, the sealing of the mold will have problems, and the phenomenon of slurry leakage will occur. The leakage of the mold will seriously affect the appearance of the PC component, and the surface will be rough. If the size of the opening is too small, it will affect the demoulding and cause the component to be stuck.
5) Safety and practicality. Since most of the components such as stairs and balconies are large molds, the molds are large in size and heavy in weight, so in the design process, practicability and operability should be fully considered, which is convenient for workers to operate, and sufficient operating space and operating platform are left to facilitate the mold. assembly, disassembly, and operations during production.
