BENEFIT FROM OPTIMAL GREEN SAND COOLING, PREMIXING & MOISTURE CONTROL WITH THE SIMPSON MULTI-COOLER

Foundries worldwide are advancing their sand preparation systems by realizing the benefits of cooling and pre-mixing with the Simpson Multi-Cooler to produce higher quality, profitable castings. The Simpson Multi-Cooler is specifically designed to provide the mixer group with sand that is cooled to temperatures that allow optimal mulling, premixed to eliminate return sand variations and with a moisture content controlled within tight tolerances.

Sand systems with return sand temperature above 120°F (49°C) and/or wide variations in return sand properties need a proper sand cooling system. The #1 cause of sand related casting scrap as described by the Metalcasting Industry Researchers is hot sand. If you have a hot sand problem and your foundry is experiencing casting defects, the Simpson Multi-Cooler is the solution. These are the most common hot sand casting defects that the Multi-Cooler can correct:

• Pin Holes – Cavities in casting surface, either spherical, flattened, or elongated
• Sand Inclusions – Surface or sub-surface particles of sand, dross, or oxides which are embedded in the metal
• Washes – Rough spots and areas of excess metal caused by erosion of the mold
• Rough Surface – Casting surface that lacks required degree of smoothness
• Sand Stickiness – Excess metal on the surface of the casting caused by a portion of the mold face remaining on the pattern
• Broken Molds – Molds that are not strong enough to withstand pouring stresses
• Crushes – Indentations in the castings

To release the heat from a sand grain’s surface a certain amount of energy in the form of air and water is required. Thoroughly cooling sand takes time; with the Simpson Multi-Cooler cooled sand can be efficiently achieved.

The Simpson Multi-Cooler is a continuous, on-demand evaporative cooler that has many innovative design features that improve sand quality and produces higher quality castings. Key design features include:

• Pre-mixing with back-blending provides continuous control over retention time to maximize cooling efficiency
• Intensive mixing of sand to remove inconsistencies and create intimate contact between sand, air, and moisture to maximize heat transfer capabilities
• Continuous monitoring of incoming sand temperatures and intensive fluidization of retained sand allows for high-efficiency cooling to below 120°F (49°C) or 10°C over ambient
• Controlled addition of moisture to absorb heat and control discharge moisture percent to 2.0% +/-0.2%
• Designed for durability, ease of use and low maintenance along with a compact design that integrates easily into existing sand systems

Integrated Simpson Moisture Control System
Fully integrated into the Simpson Multi-Cooler is the Simpson Moisture Control System (MCS).This advanced moisture control system was designed using the latest technology and utilizes sand temperature and conductivity (moisture) data. The data is collected from sand within the Multi-Cooler to continuously monitor and make real time adjustments to the water addition rate. Any large fluctuations in the incoming sand moisture and temperature are compensated for and the correct water addition is automatically controlled. The MCS is able to maintain tight moisture control of the sand being discharging from the Multi-Cooler.

The MCS monitors the exhaust air temperature which is correlated to the actual sand temperature within the Multi-Cooler body. The MCS also continuously measures the conductivity of the retained sand mass within the Multi-Cooler and calculates the water demand requirements that are automatically sent out to the Simpson supplied water manifold.

The MCS includes multiple color display screens that visualize the process. Information displayed includes:

• The real time exhaust temperature,
• The real time conductivity data,
• The water manifold valve state,
• The charge belt temperature trend,
• The water flow rate trend,
• The average water flow rate,
• And the trend data for the moisture and probe voltage PID loops,
• While also including alarm messaging and alarm summaries.

The system is capable of displaying in multiple languages and both imperial and metric measurement units.