717. 273. 2111

Refractories are important to high temperature manufacturing for their thermal insulation properties and are commonly used to protect personnel and equipment.  They are critical to industries such as glass, ceramic, and metallurgy. In general, refractories are used for temperatures in excess of 2,000°F, for applications such as the melting of glass or metal, or the curing of ceramic wares.

Alumina (neutral) and magnesite (chemically basic) represent two common ingredients used in the production of refractories, which involves a mixing step which is critical to the quality and cost of the final product. Mixing is critical because raw materials can be vastly different in physical characteristics, such as particle size (from powdery to 1/4” granular) and bulk density (35 pcf for graphite to 100+ pcf for minerals).

For castable refractories, the mixing cycle first goes through a dry mixing phase where all solid raw materials are homogenized. The dry mixing phase may be followed by water addition and an ensuing wet mixing phase. To facilitate mixing, it is best to go through dry mixing of powdery and granular ingredients before adding liquids. This is because inter-particle attraction is generally lower with dry materials, making it easier for them to mingle.

Modern best practice suggests mixing be accomplished at the highest practical intensity to maximize production rate. High intensity means using high mixing tool speeds during both dry and wet mixing–provided wear, ventilation and other issues are acceptable. One of the advantages of high-intensity mixing is a shorter overall mixing time. In general, the same degree of mix quality can be achieved in ¼ of the time if the tool speed is doubled. A typical batch mix cycle for castables should be approximately 4 minutes, including material charge and batch discharge time with minimal residue after discharge.

Incomplete or deficient mixing can lead to premature failure of the refractory. Only a decade or two ago, a typical glass tank needed to be relined every 8-10 years. The efforts and downtime are extensive for such an exercise. With properly mixed and better quality refractories installed, many glass producers now go through a cold shut down every 15-20+ years, reaping substantial savings. Such advances are attributed to improvements in formulation, including mixing, in the manufacture of refractories.

A Lancaster Products K-Series Mixer can impart custom-designed levels of mixing intensity, varying tool speeds at will through the use of VFD control. The intensity range typically covers one order of magnitude, or roughly 1-10, however ranges as high as 1-100 are also possible. This wide range of intensity is more than adequate to handle any refractory applications for very short cycle times. Compared with other types of mixers, the flexibility to vary the mixing intensity input represents one of the advantages a counter-current, rotating pan mixer has over other types of mixers which have limited latitude in intensity adjustment.

Contact us today to discuss how a Lancaster Mixer can satisfy you refractory mixing requirements.

[javascript protected email address]

717-273-2111

Lancaster Products
920 Mechanic Street
Lebanon, PA 17046

Local: 717.273.2111
Toll Free: 800.447.7351

Sitemap | Privacy Policy

© Lancaster Products

Lancaster Products Multi Tool Mixing Advantage

Since the introduction of the original K-series mixer in 1986, Lancaster Products High Shear Mixers have been designed to produce the best mixing and pelletizing results for our customers. Lancaster Mixers superior performance is due to our multi-tool configuration, counter current mixing action and variable tooling speed capability. Multi Tool Configuration Lancaster Mixers can be configured with three independent variable speed mixing tools: the mixing rotor, the plow and the rotating pan. These three tools work in concert to provide the best mixing results. The primary mixing tool is the high-speed rotor. The plow and rotating pan both work to move material into the main rotor’s path. The three mixing tools are so efficient at mixing, there are no dead spots inside of the mixing cavity and every piece of material passes through the mixing rotor every few seconds. Additionally, a sidewall scraper is positioned against the pan sides to prevent caking and buildup of material on the pan itself.
read more

Benefits of Owning Lancaster Products’ High Shear Mixers

We are very thankful for all the positive feedback we’ve received over the past 30 years of enhancing materials processing projects for our clients with our high shear mixers. So, we decided to highlight some of the reasons our customers choose to partner with Lancaster Products to optimize their industrial mixing and pelletizing processes.
      1. Practical Machine Design
      2. Easy Maintenance
      3. Easy Clean Out
      4. Customization
      5. Low Total Cost of Ownership
read more