This standard is applicable to natural marble slabs for buildings, and natural marble slabs for other purposes can also be used for reference.

(a) product classification: (according to the shape is divided into the following categories)

1 universal board

2 circular arc plate-decorative plate with the same curvature radius of decorative surface contour lines everywhere.

Grade:

1: According to the deviation of specifications, dimensions, flatness tolerance, angle tolerance and appearance quality, the ordinary version divides the plate into three grades: excellent product (a), first-class product (b) and qualified product (c).

2. According to the dimensional deviation, straightness tolerance, line profile tolerance and appearance quality, circular arc plates are divided into three grades: excellent product (a), first-class product (b) and qualified product (c).

3. Marking

Marking sequence: raw material place name, description of pattern tone characteristics, marble; Quantity, category, size, grade and standard number.

(2) Technical requirements

Allowable deviation of specifications and dimensions:

1 length and width. Positive and negative 1mm is the first-class product, and positive and negative 1.5mm is the qualified product.

2. Plates with a thickness of/kloc-0 12mm±0.5mm are excellent products, plus or minus 0.8mm are first-class products, and plus or minus 1mm are qualified products. Plates with a thickness greater than12mm1mm are excellent products, positive and negative 1.5mm are first-class products, and positive and negative 2mm are qualified products.

3. The minimum wall thickness of the arc plate should be less than 20mm, and the deviation of the chord length+1mm is first-class and first-class, and the chord length+1.5 mm is first-class. Height plus or minus 1mm is first-class product, first-class product, plus or minus 1.5mm is qualified product.

4 The allowable tolerance of flatness in the length direction is 800 mm;

0.7mm for top-class products, 0.8mm for first-class products and ±65438±0mm for qualified products.

5 allowable tolerance of arc straightness and profile. According to the allowable tolerance of the board height of 800mm and the line profile of 0.8mm, 0.8 mm is the first-class product, 1mm is the first-class product, and 1.2mm is the qualified product.

6 Angle 400mm column, the allowable tolerance of 0.3mm is first-class, the allowable tolerance of 0.4mm is first-class, and the allowable tolerance of 0.5mm is qualified.

7. Allowable tolerance of arc end angle: 0.4mm for first-class product, 0.6mm for first-class product and 0.8mm for qualified product.

8 The included angle between the front and side of flat-fell seam plate shall not be greater than 90 degrees.

9 The side angle of circular arc plate should be not less than 90 degrees.

(3) Appearance quality

1 The tones of the same batch of stones should be basically coordinated, and the patterns should be basically the same.

2 The quality requirements for the defects in the front appearance of the layout shall meet the following requirements:

The crack length shall not exceed 10mm, the missing edge length shall not exceed 8mm, and the width shall not exceed1.5mm; ; The missing angle shall not exceed 3mm in length and 3mm in width; The stain area is not more than 6 square centimeters; The diameter of sand holes shall not exceed 2mm.

3 Marble plates are allowed to be bonded and repaired, and the physical properties of the plates should not be affected after bonding and repairing.

(4) Testing method of facing

1 Test method for compressive strength after drying, water saturation and freeze-thaw cycle.

Test method for dry and water-saturated flexural strength.

Test method for bulk density, true density, true porosity and water absorption.

4 wear resistance test method.

5 Shore hardness test method.

6 acid resistance test method.

7 test method for detecting the suspension strength of combined unit of flat pendant.

Test method for detecting structural strength of stone suspension system by uniform static pressure difference.

Measurement method of mirror gloss of building decoration materials.

Test method for Bakol hardness of 10 reinforced plastics.