Gasbond Premium TDS
THE GASBOND PREMIUM PROCESS
This procedure presents an efficient and cost-effective approach for creating foundry cores and molds, utilizing standard sand-processing and core-making machinery. The method involves blending dry sand with Gasbond Premium binder within a muller. Following this, the mixture is compacted, vibrated, or injected into a core box. The transformation of core sand into a rigid state is achieved by circulating CO2 gas throughout the core. Once hardened, the core is immediately prepared for application, eliminating the need for additional drying or heating.
CORE SAND MIXTURE
Gasbond Premium is recognized for its high viscosity, ensuring compatibility with various core sand types. The usage ratio of Gasbond Premium ranges from 2% to 5%, adjusted according to sand granularity, additional substances, and the casting category. Optimal sand conditions include the absence of clay and a moisture content below 0.2%. Traditional core sands are recommended. The mixture process should occur at ambient temperature (prior to incorporating Gasbond Premium, any shakeout-facilitating additives should be blended with the sand). Typical mixing duration with a standard muller spans 4-5 minutes. The resulting mix is either utilized promptly or stored in sealed containers. To avert desiccation and air-induced solidification when stacked, it is advisable to shield with damp cloths.
CORE CREATION
A variety of conventional techniques are applicable for core fabrication. The sand mixture is characterized by excellent flow properties albeit limited initial strength. For cores solidifying within the mold, initial strength is less critical.
GASSING PROCEDURE
The hardening of sand within the core box is executed by diffusing CO2 gas throughout the mass. To achieve consistent hardening, it is crucial for the CO2 to infiltrate the entire core. Typically, gassing concludes within 10 to 30 seconds for small to medium cores, whereas larger cores may necessitate multiple gassing points and extend to several minutes. The resulting cores must be stored under controlled humidity to prevent moisture impact.
It is common for gassed cores to require an additional agent to enhance surface robustness and mitigate handling abrasion. For instance, SFP's SHURBOND, an air-curing spray, quickly increases surface strength to parallel that of a heat-treated core, simultaneously obstructing moisture absorption, particularly during humid periods.
