So far, the domestic mortar spraying machine has not been fully promoted in the construction industry. The reasons are as follows:
1. Ordinary dry powder mortar cannot be directly used for machine spraying: In the case of manual application, the only considerations during the batching process are the excellent performance and good workability after consolidation. In order to be able to adapt to the mechanical spraying performance of mechanized construction, the control and adjustment of mortar consistency, gradation, additives and other indicators are more stringent to ensure the pumpability, water retention, retardation and ease of mortar. Purpose to prevent pump blocking and pipe blocking due to material segregation
2. Need to find the spraying equipment suitable for China's national conditions: There are many domestic manufacturers of mortar pumps. The seemingly simple mortar pumps have low entry barriers and uneven quality. In addition, the use of mortar pumps has requirements for mortar raw materials and needs to properly guide customers According to the construction conditions and the needs of the material, the mortar pump is correctly selected, and the mortar material used is tested and adjusted to meet the requirements of mechanized construction.
Many machinery and equipment manufacturers are not familiar with the application of mortar, which makes many customers spend a lot of time and energy to ponder without knowing the materials, machinery, and construction technology. It is difficult to avoid multiple failures. When talking about the mechanized construction of mortar, many people are very resistant to it, thinking that this construction process is not yet mature.
On the other hand, although the application of foreign mortar pumps is very mature, even after the introduction of foreign mortar pumps in China, the phenomenon of soil and water dissatisfaction has appeared. Foreign materials are good, mainly screw pumps. The domestic mortar materials are inferior to foreign materials, especially for cement mortar. During the use of screw pumps for large-area construction projects, the wear is generally too large and it is difficult for the construction party to accept.
Basically, all dry powder mortars are transported by dry powder pneumatic conveying devices in foreign countries. It has the advantages of a fully enclosed automatic system, no risk of mortar consolidation in the pipeline, the ability to stop work at any time, and no need to clean pipelines and conveying equipment. Wet material will only be used for flooring materials (such as ground floor and surface floor with equal flow) to pump with large flow.
However, due to the proportion of the mortar in our country and the cost, the application of the mortar on the dry powder pneumatic conveyance is basically impossible (because the proportion of the material is too large); so we started to try wet material transportation, but the biggest problem of the transportation is too long. The pipeline is prone to blockages and the equipment overcomes the cost of long-distance loss, and it takes a lot of time to clean the pipeline and conveying equipment every day.
3. Lack of a professional mechanized spraying construction team: in the construction process, there is not much difference between the mechanized spraying construction and the traditional construction process. The main difference is the subdivision of the work type and the assembly line operation, which completely breaks the large and small jobs in the traditional industry. There is no distinction between large and small workers in the strict sense of mortar mechanized spraying construction, but due to the lack of corresponding process refinement and targeted training, there are very few real professional construction teams in China.
