Posted by mining | Posted in sand | Posted on 18-01-2012
The question of Chromite vs. Zircon has always been a very difficult subject because good quality Zircon has always been a very difficult subject because of good quality Zircon sand performs extremely well, and has been used as a benchmark in the production of quality Zircon sand performs extremely well, and has been used as a benchmark in the production of quality castings over the past 20 years. castings over the past 20 years. However, during the past 6 to 8 years Zircon has become very variable However, during the past 6 to 8 years has become very variable Zircon and the so-called foundry grades are giving some foundries severe problems due to contamination. and the so-called foundry grades Foundries are giving some severe problems due to contamination.
When the cleanliness of Chromite is at turbidity levels of less than 100 ppm Chromite will perform better When the cleanliness of Chromite Chromite is at turbidity levels of less than 100 ppm will perform better than Zircon in the heavy steel foundry environment. Zircon than in the heavy steel foundry environment. This is supported by our customer list, which This is supported by our customer list, which includes the majority of the heavy high quality steel foundries worldwide. includes the Majority of the heavy high quality steel Foundries worldwide.
It is also important to note that at today’s prices (2010) Chromite sand is approximately half the price of It is also important to note that at today’s prices (2010) Chromite sand is approximately half the price of a good quality Zircon sand that would perform similarly to Chromite. Zircon sand that would perform similarly to a good quality Chromite.
Steel foundries have always had their favourite material to use. Their Steel Foundries have always had a favorite material to use. In many instances it was the In many instances it was the geographical location that decided whether Chromite or Zircon was used. Whether Zircon or Chromite was decided that geographical location used. This is particularly true of the This is particularly true of the USA as they have deposits of very good quality Zircon in Florida. USA as they have very good quality deposits of Zircon in Florida. In the USA today very few In the USA Today, very few foundries are using Zircon as the preferred material. Foundries are using Zircon as the preferred material. Chromite costs less and the foundries which have Chromite which costs less and has the Foundries changed over have found that casting quality has not suffered. found that has changed over the casting quality has suffered a note.
Historically the development of Zircon sand recovery systems was always ahead of Chromite recovery Historically the development of recovery systems Zircon sand was always ahead of the Chromite recovery systems. systems. Today this is not the case, Chromite recovery systems are available that will recover up to Today this is not the case, Chromite recovery systems are available that will recover up to 85% Chromite with less than 1% silica contamination. Chromite with 85% silica, less than 1% contamination. These systems also clean the silica sand with a These systems also clean the silica sand with a Chromite content of less than 1%. Chromite content of less than 1%. The recovered Chromite can be blended with new Chromite up to a The recovered Chromite Chromite can be blended with up to a new ratio of 80% reclaim 20% new. Reclaim 20% ratio of 80% new. On heavy wall castings a 50/50 blend is used. A 50/50 blend is used on heavy wall castings. Foundrymen have found that the new Chromite sand has eliminated the problem of double skin defect
Foundrymen have found that the new Chromite sand has eliminated the problem of double skin defect that has been associated with Chromite over the years. Chromite has been associated with that over the years. It is also important to note that the advance in It is also important to note that the advance in foundry technology with regard to feeders (risers) and ingating have also been very beneficial to foundry technology with regard to feeders (risers) and ingating have been also very Beneficial to surface finish. surface finish.
The goal is to continue with product improvement and maintain the edge over competition. The goal is to continue with product improvement and Maintain the edge over the competition. This will be This Will Be achieved by partnerships with customers, shipping agents and technical consultants who are the Achieved by Partnerships with customers, shipping agents and technical consultants who are the experts in advanced foundry technology. Experts in advanced foundry technology.