PRECISION CASTING PATTERN COMPOUND AND METHOD FOR PRODUCTION THEREOF

摘要

Precision casting pattern compound and method for production thereof. The invention relates to machine building technology, in particular, to precision casting pattern compounds with improved physical and mechanical properties. The objective and the effect are attained by that the precision casting pattern compound containing lignite wax, ceresin, rosin, polyethylene wax, triethanolamine and paraffin, contains disproportionated rosin as rosin at the following ratio of components, wt.%: lignite wax - 3-35, ceresin - 5-20, disproportionated rosin - 5-10, polyethylene wax - 5-10, triethanolamine - 2.5-5, paraffin - the rest. For the first time the invention uses for a production of pattern compound the disproportionated rosin with the following properties: T=65.0°C, SF=163.0 mg KOH/g, modified by triethanolamine that according to acute intragastric toxicity parameters as per GOST 12.1.007-76, belongs to the 4-th hazard class - low-hazard substances, which permits its use in the national economy. The objective and the effects are attained by that in the method of precision casting pattern compound production, wherein disproportionated rosin is produced from rosin in reactor at a temperature of 220±5°C during 1-2 h in the presence of 0.5-1.0 wt.% by mass of iodine-containing catalyst, thus produced disproportionated rosin, after neutral substances stripping, is mixed with triethanolamine at a temperature of 100-140°C, held in the heated state for 0.5-1.0 h until salt formation; then ceresin, polyethylene wax, lignite wax and paraffin heated to the melting point are added, and the mixture is held until creation of the pattern compound. Disproportionated rosin was not used earlier for this purpose (increased thermal stability and thermal resistance of the pattern compound).