USR. Secondary Attrition Unit
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USR is a registered SINTO Corporation, Japan. This equipment is being manufactured under license by OMEGA FOUNDRY MACHINERY, Ltd., and distributed in the Spanish market by EUSKATFUND, SL.
Japan, silica sand importer country for lack of this natural resource, and historically sensitive to environmental problems the country was the birthplace of the development of sand recovery processes in the world of foundry.
SINTO,recorded the USR and WSR models for recovering silica sand for foundry, especially in moulding processes where inorganic binders are used (silicate) and semi inorganic (alkaline phenolic resin). Although they are struggling processes for recovery, you can recover up to 90% with the implementation of the USR in their recovery process.
WHAT IS THE USR?
Secondary attrition Unit is comprised of one or two houses of attrition (depending on model) with high speed bearings. The chamber are electrically controlled and rotary action forces the sand that enters the unit to be released to the periphery of the cover. To help remove the resin, a ceramic rollers rub against sand with controlled and adjustable pressure, by pneumatic cylinders arranged in the base unit. The sand is retained for a short time at the top of the chamber, before being evacuated or sent to the second chamber in the case of dual-chamber models. Then, the sand of the second chamber is moved outside, the entry of the sand from the first chamber. The processed sand that has fallen from the second chamber is moved through a classifier located below the chamber, where by means of a fluid bed are separated the fines (mainly resin powder).
IDEAL PARAMETERS FOR RECOVERY ELEMENTARY (MECHANICAL).
- Good sand ratio/metal - 4:1 or better.
- Iron casting.
- Organic binders.
- Low percentage of binder.
In these cases, foundries may recover higher levels of sand and maintain good characteristics thereof. If you Not in this category, two options to regenerate its reclaimed sand.
HEAT RECOVERY
- High initial cost for investment.
- High operating costs - energy consumption, ....
- You can not recover inorganic binders.
- You must add an additive to reclaim binder sand with alkaline phenolic resin.
- Some sands can not be recovered due to changes in morphology.
- Requires emission controls regularly to ensure that local standards are maintained.
- AGAINST THE AGREEMENT OF REDUCING CO2 EMISSIONS
USR. SECONDARY ATTRITION UNIT
- Eliminate binder content mechanically. Also in the case of inorganic binder (silicate) and organic semi (alkaline phenolic resins), and conditions without damaging the grain size.
- Low initial investment cost. Rapid payback. Without CO2, having no heating gas.
- Low cost of energy to operate, contrary to what happens with thermal reclamation, with reduced cost of spares, as high wear items are ceramic, which guarantee long life (3,000 hours) .
- Controlling the binder removal rate by adjusting various parameters. (The pressure on the rings, ring thickness, drum rotation speed, number of passes from the sand, one or two per unit depending on model).
- You can work with any sand base.
USR. MARKET SITUATION
Today, there are facilities worldwide USR. Of course, Japan is the dominant country with 180 installations. In the rest of the world have sold 18 equipmetns in the last two years, despite the severe economic crisis because of their rapid depreciation, with a high rate of satisfaction among founders, helping to minimize waste and avoid emissions of CO2 into the atmosphere.
