COT BOX is a phenol formaldehyde resin which is activated by Isocynates & Catalysed by amine gas. The system is humidity resistant & water based coatings can be used without any problems on cold box cores. The starting point of the development of cold box process on polyurathane base was the fact that the machinery heating required in the hot box process was considered to be a substantial disadvantage.
Dry Silica sand having AFS No-50-60 and free from carbonates is best suited for the COTBOX system. Both batch type and continuous mixers can be used for sand Preparation and the bench life of sand mixture is around 45 mins to 1 hrs depending upon ambient condition. COT BOX PART A & COT BOX PART B are mixed together with sand and the sand mixture is cured within seconds when a gaseous amine Catalyst (COT BOX PART C) is passed through the mixture.. COT BOX PART-A (Resin) 0.8 to 1.0% based on dry sand COT BOX PART-B (Isocynate) 0.8 to 1.0% based on dry sand COT BOX PART-C (TEA Catalyst) 0.1 to 0.2 % (in form of gas) The sand mixture is blown in the core box and amine gas is passed through the sand at controlled pressure and temperature. Excess amine catalyst COT BOX purged by passing dry air and core is stripped from the core box. Typical cycle time is less than one minute. Chemical dryer unit between core shooter and compressed air is must. Moisture in compressed air deteriorates quality of core.
COT BOX PART A | 50 kg in M. S. Drum & 200 kg in M. S. Drum |
COT BOX PART B | 50 kg in M. S. Drum & 200 kg in M. S. Drum |
COT BOX PART C | 10 kg in M. S. Tins & 150 kg in M. S. Drum |
COT BOX PART A & COT BOX PART B has a shelf life of 6 months when stored in cool & dry places. COTBOX PART C has a shelf life of 1 year when stored in cool & dry place.
Direct contact with skin or body should be avoided.
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