Black Limestone Steps

Enhance your outdoor space with Black Limestone Steps. Made from durable limestone, these steps provide a stylish and practical solution for creating a beautiful walkway or staircase. With a sleek black color, these steps add a modern touch to any landscape. Upgrade your outdoor design with Black Limestone Steps.

There are two types of black limestone steps: general-shaped slabs (square or rectangular slabs) and special-shaped slabs (slabs with other shapes). In order to ensure that the seams are neat after the slabs are laid, the national standards stipulate the allowable deviation of the black limestone steps specifications, the allowable limit tolerance of flatness, and the allowable limit tolerance of the angle.

 (1) Description of allowable deviation of specifications: When the thickness is less than or equal to 15mm, the allowable limit deviation of thickness on a plate is 1.0mm (that is, it is thick or thinner than the standard thickness of 1.0mm, and it is unqualified if it exceeds this value. Product); when the thickness of the plate is greater than 15mm, the allowable limit deviation of the thickness on the same plate is 2.0mm. The length and width of the board shall not exceed the specified value, but may be slightly lower than the specified value. When measuring the size, the scale value is 1． A 0mm steel ruler measures the length and width of the plate; a vernier caliper with a reading value of 0.1mm is used to measure the thickness of the plate. ’

(2) Permissible limit tolerance of flatness Flatness refers to the flatness of the plane of the board, which affects the flatness of the entire veneer after paving the black limestone steps. When measuring, the steel flat ruler that meets the measurement requirements is placed on the two diagonal lines of the plane of the tested plate. Because the plate cannot be very flat, there will be a gap between the measuring flat ruler surface and the board surface, which can be measured. Feeler gauge to measure the gap size. If the length of the board to be inspected is greater than 1000mm, a steel flat ruler with a length of 1000mm shall be used for the inspection along the diagonal in sections. The maximum gap size represents the flatness limit tolerance of the plate.

(3) The allowable limit tolerance of the angle For the jointed board, the angle between the front and the side shall not be greater than 90. The allowable limit tolerance of the special-shaped plate angle is determined by the supplier and the buyer through negotiation. Angle refers to the angle between two adjacent sides on the plane of the sheet. The angle between the two adjacent sides of the general plate should be 90o. When measuring, use the specified 90" steel square, the long side of the square is close to the long side of the plate, and the short side is close to the short side of the plate. Use a feeler gauge to measure the gap size between the plate and the short side of the square. Measure the plates according to the regulations. For two opposite corners or four corners of the plate, the maximum gap size among them is taken as the allowable limit tolerance value of the angle.