ICS 81.080Q 43JCBuilding materials industry Standard of the Peoples Republic of ChinaJC/T 20362010Magnesia alumina spinel bricks for cement kiln水泥窑用镁铝尖晶石砖（English Translation)Issue date:201X - XX - XXImplementation date:201X - XX - XXIssued by Ministry of Industry and Information Technology of the Peoples Republic of ChinaJC/T 20362010ForewordChina Building Materials Federation is in charge of this English translation. In case of any doubt about the contents of English translation, the Chinese original shall be considered authoritative.This standard is drafted in accordance with the rules given in the GB/T 1.1-2009.This standard was proposed and prepared by China Building Materials Federation.The interpretation of this standard is entrusted to China Building Material Test & Certification Center and National Quality Supervision and Test Center of Refractory Materials for Building Materials Industry.This standard is issued for the first time.IJC/T 20362010Magnesia alumina spinel bricks for cement kiln1 Scope This standard specifies the terms and definitions, classification and marking, technical requirements, test methods, inspection regulation, marking, packaging, transportation and storage, and certification of magnesia alumina spinel bricks for cement kiln.This standard is applicable to magnesia alumina spinel bricks for cement kiln.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated reference, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.GB/T 2997 Test method for bulk density, apparent porosity and true porosity of dense shaped refractory productsGB/T 5069 Chemical analysis of magnesia-alumina refractoriesGB/T 5072 Refractories-Determination of cold compressive strengthGB/T 7320 Refractories-Determination of thermal expansionGB/T 7321 Sample preparation for testing of shaped refractory productsGB/T 10325-2001 Shaped refractory products- Sampling and acceptance testingGB/T 10326-2001 Refractory products- Inspections of dimension appearance and sectionGB/T 16546-1996 Shaped refractory products-Packing, marking, transportation and storageGB/T 17912-1999 Refractory bricks for rotary kilns- DimensionsGB/T 18257-2000 Refractory bricks for use in rotary kilns-Hot-face identification markingYB/T 370 Test method for refractoriness under load of refractory products (non-differential, with rising temperature）YB/T 376.1 Refractory products-Determination of thermal shock resistance (water quenching)YB/T 376.2 Refractory products-Determination of thermal shock resistance ( air quenching )3 Terms and definitionsFor the purpose of this standard, the following terms and definitions apply.magnesia alumina spinel bricksmagnesia alumina spinel bricks are refractory products that are mainly made from magnesia, magnesia-alumina spinel or alumina-magnesia spinel after pressing and firing4 Classification and marking 4.1 Classification4.1.1 According to the content of MgO and Al2O3, the products are divided into three brands， MLJ-80, MLJ -85 and MLJ -90.Note：In the brand, M, L and J are the Chinese Pinyin initials of magnesium, aluminum and tip, the Arabic numerals are the mass fraction of magnesium oxide.412 Brick numbers of products are classified according to GB/T 17912-1999.42 Marking421 The marking order of products is product name、brand number、brick number and standard number.For example: The magnesia alumina spinel brick with MLJ-80 of brand number and B 620 of brick number is marked as: Magnesia alumina spinel brick MLJ-80 B 620 JC/T 20362010. 422 The products shall be marked with hot surface, the marking as specified in GB/T 18257-2000.5 Technical requirements5.1 The permissible dimensional tolerance and the appearance of products as specified in Table 1.Table 1 The permissible dimensional tolerance and the appearance quality of products Unit in millimeterItemIndexTolerance of length and height2.0The large end and small end dimension of wedge brickAllowable deviation1.5Deviation of wedge degree1.0Warpage0.5%Corner defect20 allowed 20a+b+c50 2 places allowed 50 not allowedEdge defect30 allowed 30e+f+g60 3 places allowed 60 not allowedCrackWidth0.1Allowed0.10.25Crack length400.25Not allowedNote：The permissible dimension tolerance and appearance quality of special requested products may be negotiated by the providers and the demanders.5.2 The physical and chemical properties of products as specified in Table 2.Table 2 Physical and chemical properties of productsItemIndexMLJ-80MLJ-85MLJ-90Chemical componentsMgO (%)802.5852.5902.5Al2O3 (%)1195SiO2 (%)1.5Physical propertiesBulk density（g/cm3）