5、 Chord length cutting and height adjustment stage
Equipment: Double-blade cutting machine, Italian bridge cutting machine.
Process and process technical requirements
Process 1: Production of positioning mold
On the workbench of the bridge cutting machine or double blade cutting machine, use Hercules adhesive or other adhesives to bond four suitable block materials to the workbench according to the chord length and height of the arc plate, and ensure that the two are in a straight line.
Use the profiling function of the Italian bridge-cutting machine to simulate the four positioning blocks to form a concave arc surface with the same radius as the arc surface of the same circular arc plate, or use a bridge-cutting machine or a double knife-cutting machine to cut the upper positioning block into an inclined plane according to the curvature of the arc surface
Before cutting the chord length and adjusting the height, the perpendicularity of the tool used in the machine tool and the workbench should be checked with a dial gauge and a wide seat angle ruler.
Regular inspection: Carefully lift the polished arc onto the prepared positioning module, and place a layer of fine sandpaper to prevent scratches on the smooth surface of the arc plate. When the arc surface busbar of the arc plate matches the contact surface of the positioning module, the chord length can be cut.
Procedure 2: Adjust the cutting angle and chord length parameters of the arc plate.
Process 3: Trim the height of the circular arc plate. Before cutting, a positioning mold for cutting height should also be made on the workbench of the machine tool used. Just process the positioning module. The distance between the two positioning blocks should be greater than the chord length of the circular arc plate. When trimming, place one side of the circular arc plate tightly against one side of the positioning module, and fix the other side tightly with a wedge to cut the height.
Process 4: Inspection. The quality inspector inspects the angle, chord length, height, and verticality of each cut circular arc plate using a protractor, tape measure, and wide seat angle ruler according to the relevant quality inspection standards for stone handicrafts.
6： Final inspection stage of finished products
A Finished product quality standard
Chord length error 0-0.5 mm
Height error 0-0.5 mm
Angle error ± 0.5 mm
For some hollow circular arc plates, the angle error can reach more than 1-2 degrees. The straight-line error on both sides is 0.5 mm. The difference between the curvature and the standard template is ± 0.3 mm, and the transition of the curved surface is natural and smooth, with no obvious concave or convex feeling when touched by hand.
Whole circle splicing, with adjacent arc plates matching the arc surface. The arc surface of the upper and lower arc plates should be spliced, and the lines on both sides should be on the same plane, but the error can be 0.5 mm.
B Appearance quality:
Color pattern: The color of the entire cylinder must be consistent. If the color of similar cylinders cannot be guaranteed to be consistent within the same plane area, refer to the plane installation layout and gradually transition the colors, but the pattern must be consistent unless otherwise requested by the customer. Usually, the direction of the grain is taken along the height direction. If the material has obvious and regular grain, the grain direction should be perpendicular to the upper and lower end faces.
Glossiness: Compared with standard sheets imported from Italy, the glossiness of top-grade products reaches 100%, and top-grade products reach 95%.
The appearance should comply with the national stone quality inspection standards
C inspection items:
Chord length, height, straightness of busbar, straightness of busbar edge, roundness, internal and external angles, color, texture, luminosity, verticality, appearance quality, and angle.
D inspection method:
Use a steel tape measure to check if the chord length and height meet the quality inspection standards for stone handicrafts.
Use a wide seat angle ruler to check the verticality of the edge line and height end face of the circular arc plate.
Use a photometer to check the glossiness of the curved surface of the circular arc plate.
Visually inspect the appearance quality of the circular arc board surface.
Use the full circle splicing method to spot-check the splicing effect, and inspect the seams, and internal and external corners.
Use the upper and lower layer splicing method to spot-check the splicing effect, and inspect the splicing seams and internal and external corners.
Touch the arc surface of the arc board with your hand to check the arc degree of the arc board surface.
Number and marking method of E-arc plate:
Strictly follow the installation drawing to number the colors and patterns one by one and pack them into the warehouse. Arrange highly consistent items in the same circle and string lengths in the same column. Number according to the method shown in the following figure.