GB/T 23452-2025Natural sandstone slab for building (English PDF)

4.1 Classification

4.1.1 Classified by mineral composition and content.

a) QZ (Qinze-type sandstone). Sandstone with a quartz content of 45%–90%;

b) Quartz Sandstone (QS). Sandstone with a quartz content greater than 90%;

c) Tuff (QN). Volcanic clastic rock composed of volcanic ash and fine rock fragments. 4.1.2 Classified by shape.

a) Surface Mount (MB);

b) Standard type sheet (PX);

c) Irregularly shaped plates (YX).

4.2 Level

Classified by processing and appearance quality.

a) The raw boards are classified into three grades. A, B, and C, based on their thickness deviation, flatness tolerance, and appearance quality;

b) Standard boards are classified into three grades, A, B, and C, based on dimensional deviations, flatness tolerances, angular tolerances, and appearance quality.

4.3 Marking

4.3.1 Name. Use the name or number specified in GB/T 17670.

4.3.2 Marking order. name, category, specifications, grade, standard number.

Example. 600mmx600mmx30mm standard grade A slabs processed from Sichuan red sandstone (mixed sandstone) blocks are marked as.

5.1 General Requirements

5.1.1 Commonly used dimensions of sheet metal are shown in Table 1.The specifications and dimensions of irregular-shaped sheets and standard-shaped sheets with special requirements shall be determined by the supplier and the buyer through negotiation. Table 1 Sheet Size Series The unit is millimeters.

Side length series. 300, 305, 400, 500, 600, 800, 900, 1000, 1200, 1500 Thickness series (H). 10, 12, 15, 20, 25, 30, 35, 40, 50, 60, 70, 80, 100, 150 5.1.2 The boards are permitted to be bonded and repaired. Bonding and repair should not affect the decorative effect of the boards, nor should they reduce the physical properties of the boards.

5.2 Processing quality

5.2.1 The flatness tolerance and thickness deviation of the raw board shall conform to the provisions of Table 2.

Table 2 Flatness tolerance and thickness deviation of raw board The unit is millimeters. project Technical requirements ABC Flatness tolerance. 1.50, 1.80, 2.00 Thickness (H) deviation H<=12 ±0.5 ±0.8 ±1.0 12 < H<=150 ±1.0 1.5-1.0

2.0 -1.0

5.2.2 The dimensional deviations of standard-sized plates shall conform to the provisions of Table 3.

Table 3 Dimensional Deviations of Standard Plates The unit is millimeters. project Allowable deviation ABC Length and width. 0-1.0 -1.5 Thickness (H) H<=12 ±0.5 ±0.8 ±1.0 12 < H<=150 ±1.0 1.5-1.0

2.0 -1.0

5.2.3 The flatness tolerance of the standard plate shall conform to the provisions of Table 4.

Table 4 Flatness Tolerances for Standard Plates The unit is millimeters. Sheet length (L) Tolerance requirements ABC L<=400 0.60 0.80 1.00 400 < L <= 800 1.20 1.50 1.80 L >800 1.50 1.80 2.00 5.2.4 The angular tolerance of the standard plate shall conform to the provisions of Table 5.

Table 5 Angle Tolerances for Standard Plates The unit is millimeters. Sheet length (L) Tolerance requirements ABC L<=400 0.30 0.50 0.80 L >400 0.40 0.60 1.00 5.2.5 The angle between the front and side of a standard sheet should not exceed 90°.

5.2.6 The effective dimensions and geometric tolerances of irregularly shaped plates shall be determined through negotiation between the supplier and the buyer. Thickness deviation shall meet the thickness requirements in Table 3, and flatness shall be...

Tolerances, based on the smallest rectangular dimension of the external outline, should conform to the provisions of Table 4.

5.3 Appearance Quality

5.3.1 The color tones of boards from the same batch should be basically harmonious, and the patterns should be basically consistent.

5.3.2 The appearance defects on the front of the sheet material shall conform to the provisions of Table 6.

Table 6 Requirements for Front Appearance Defects Defect Name Specification Content Technical indicators ABC Number of cracks with a length >= 10 mm. 0 missing edge a Length <= 8mm, width <= 1.5mm (length <= 4mm, width <= 1mm not allowed) (To be counted), the number allowed per meter length (pieces) missing corner a Along the edge of the board, the length <= 3mm and the width <= 3mm (length <= (Width <= 2mm is not counted), the allowed number of pieces per board (pieces) Sand hole diameter < 2mm 0 Not obvious Yes, it doesn't affect anything. Decorative effect a. No requirements are made for the raw board.