Steel ribbed hot rolling belt surface shape and size tolerances (GB 1499-1998)
The steel ribbed data belt produced by hot rolling production technology has the characteristics of high strength, good plasticity and weldability. In order to ensure the quality requirements of steel ribbed belt and improve the production efficiency, the hot rolling production technology of steel ribbed belt standardizes the shape and size of belt surface through the national standard Steel ribbed hot rolling belt surface shape and size allowance (GB1499-1998).
The steel ribbed belt produced by hot rolling technology is mostly used in reinforced concrete structures. According to the state regulations, the hot rolling steel ribbed belt surface shape and size allowances are given in GB 1499-1998. The hot rolling steel ribbed belt surface shape and size is divided into 10 tolerance levels, please refer to the following chart:
Figure 1 Steel ribbed hot rolling belt surface shape and size tolerance
Table 1 Steel ribbed hot rolling belt surface shape and size tolerance table
Tolerances on the shape of hot rolled steel ribbed belt is divided into two categories: local curvature and inclination. The local curvature means the local shape of steel ribbed belt surface. The local curvature is classified into 10 types according to the deviation level. The allowable range of local curvature is 0 ～20/1000. The inclination means the angle at which the steel ribbed belt surface is cut. The allowable range of inclination is ≤5/1000, and the average value of local minimum width of the steel ribbed belt should not be less than 98/1000.
In terms of dimensions, the steel ribbed hot rolled belt surface size assumption is divided into 5 parts, namely width, height, wave spacing, wave height, wave width. The allowable deviation range of these 5 parts is shown in the table below.
Table 2 Steel ribbed hot rolling belt surface size allowance table
We can also refer to the figure below to check the steel ribbed hot rolling belt surface shape and size tolerance.
Figure 2 Steel ribbed hot rolling belt surface shape and size tolerance
In accordance with the requirements of GB1499-1998, thick steel ribbed belt surface shape and sizeallowance has the following two points for attention:
1)The thickness of the ribbed belt should not be less than 8.0mm, the width of the steel belt should not be less than 40mm, and the width and height tolerance of the steel belt surface should be ≤5/1000.
2) The total length of bulging and wavy surfaces should not be greater than 5/1000, and the local minimum width of the steel ribbed belt should not be less than 98/1000.
Finally, before the hot rolling steel ribbed belt is put into use, it must be inspected by the quality inspection department to ensure that the product meets the requirements of GB 1499-1998 hot rolling steel ribbed belt surface shape and size allowance.
