德国Sika-Putzmeister公司混凝土湿喷设备说明

Dry / Wet Mix Air
Dense stream process
When substantial quantities must be applied the concrete is pumped through pipelines in a dense stream to the nozzle, where it is dispersed by compressed air. Accelerator is mixed into the concrete with the compressed air. The nozzle forms the concrete-accelerator mixture to a spray jet. Thanks to the large output capacity this method is employed on one hand for excavation stabilization in tunnel construction and on the other for stabilization of large building pits.
Thin stream process
Rotor machines convey concrete pneumatically by means of air (thin stream), so that at the nozzle the concrete must not be additionally dispersed. The advantage of this method is that both wet and dry spray concrete can be applied in this manner. Since spray machines for the thin stream process are considerably smaller than those for dense stream processing, this technique is ideally appropriate for applications in the area of refurbishments, in which spatial limitations often impede work.
Art in Architecture
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Sika Sprayed Concrete Technology
Sprayed concrete unites manifold aspects of modern concrete technology with respect to materials handling technology as well as concrete admixture chemistry. Increasing demands on cost-effectiveness, and protection of health and the environment mean that sprayed concrete technology is in continuous flux. Sika’s sprayed concrete products represent the newest generation of cutting-edge technology. They unify one hundred years of knowledge, economy and quality. Sika provides solutions! The multiplicity of demands placed on sprayed concrete today no longer admits standard solutions. Depending on the application process and the structure, varying conditions are placed on the sprayed concrete. While in tunnel construction sprayed concrete is normally employed for excavation stabilization, in open mining and on major construction sites the fixation of slopes in the foreground. In bridge refurbishments sprayed concrete is used specifically because formwork can thereby be dispensed with. Through decades of activity in the area of construction, Sika profoundly understands the difficulties of building. Sika provides solutions that surmount these challenges. Sika masters all the technologies of sprayed concrete, from wet to dry spray applications. Thanks to development of our own sprayed concrete application machine Aliva®, to research and production of concrete admixtures such as Sigunit® and Sika® ViscoCrete® and years of experience in tunnel construction and in major construction projects, Sika is the ideal partner for principal owners, planers and contractors. Innovation is the most critical property of Sika products, since only innovation masters the high demands for environmental protection, cost-effectiveness and quality. Our great success speaks for us. Major projects such as Gotthard Railway Base Tunnel or Karahnjukar are being built with Sigunit® and Sika® ViscoCrete® technology. These products are subject to the requirements of the worldwide environmental management system „Responsible Care®“, which obliges continuous performance improvement in the areas of health, safety and environmental protection.
Wet Mix
Concrete Spraying Machine
Concrete Spraying Pump
Water / Air Liquid Accelerator
Dosing Pump
Air Liquid Accelerator
Dosing Pump
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Product Technology
Selective solutions with admixtures and application technology of Sika
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Spraying Processes
Thin stream and dense stream processes
Sprayed concrete can be processed as dry or wet mix. Two different procedures are used. The choice of the spraying procedure is mainly depending on the application, construction installation, conveying amount and conveying distance. In the “dense” stream process, concrete is fed through hoses by means of pumps, whereas in the “thin” stream process the concrete is conducted through hoses by means of compressed air. Both processes are characterized of specific advantages. Thin stream process High flexibility Simple operation Lower requirements for mix design Dense stream process High spray output Low air demand Low dust generation
With sprayed concrete admixtures and application technology from Sika, individual challenges are surmounted in a targeted manner. Modern tunnel construction has first become possible with sprayed concrete. Sprayed concrete must demonstrate a sufficient workability and exhibit an extremely rapid strength development. Occupational safety and environmental protection have grown to be definitive factors in the development of admixtures for sprayed concrete. Products therefore conform to international standards and are very economical in use. By using high-quality Sika admixtures for sprayed concrete, processes can be optimized and durability is highly improved.