BS EN ISO 28763 pdf download Vitreous and porcelain enamels — Regenerative, enamelled and packed panels for air-gas and gas-gas heat exchangers — Specifications 5.6Thermal-shock resistance lf required by the enameller, the thermal-shock resistance shall be determined in accordance withAnnex A at a test temperature of 350 C on at least three test specimens prepared in accordancewith ISo 28764. After...