This standard specifies methods for determining the thickness, bulk density, resilience, permanent linear change on heating, thermal conductivity coefficient, tensile strength and shot content of refractory fiber products.
It applies to refractory fiber cotton, blankets, felts, mats, boards, papers and pre-formed products with the exception of products delivered in a wet state.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 6003.1 Test sieves - Technical requirements and testing - Part 1: Test sieves of metal wire cloth (GB/T 6003.1-2012, ISO 3310-1: 2000, MOD)
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 18930 Terminology for refractories
JJG 139 Tension, compression and inorganic material testing machines
3 Terms and definitions
For the purpose of this document, the terms and definitions specified in GB/T 18930 apply.
4 Preparation of test pieces
The test items of products shall be determined by agreement between the parties. The dimension and number of test pieces shall meet those specified in Table 1.
When the material to be tested is wound, any compressed material at the extreme ends shall be excluded. A strip shall be cut perpendicular to the length across the full material width, of sufficient size for the different tests planned; for unwound materials, sufficient number of test pieces shall be provided. The required number of test pieces of required dimensions shall be cut using a template, a knife, a saw or other method which will not damage the test piece. Avoid excess pressure from damaging the fiber during the preparation of test pieces.
For special-shaped products and products with thickness greater than 50mm and uneven texture (such as with hard shell on the surface), the sampling position for each test item shall be agreed by relevant parties and indicated in the test report.
The test pieces for tensile strength shall be taken side by side and at random along the manufacturing direction (generally the length direction) of the product. The length (230mm) direction of test pieces shall be consistent with the manufacturing direction of the product. By agreement between relevant parties, the length direction of test pieces may be perpendicular to the manufacturing direction of the product, and shall be indicated in the test report.
For test pieces having permanent linear change on heating, the rolling direction of the product shall be marked, and cushion test pieces of the same size and number shall be taken from the same product.
For test pieces for thermal conductivity coefficient, at least 3 layers shall be used when the product thickness is less than 40mm, while two layers be used when the product thickness is 40~50mm and single layer be used when the product thickness is greater than 50mm.
Table 1 List of product types as well as dimensions and number of test pieces applicable to test items
GB/T 17911-2018 The following standards are cited：
