The reason for the deviation of the parallelism between the centerline of the belt conveyor frame and the vertical centerline of the belt conveyor should not exceed 3mm. The reason for the deviation of the flatness of the middle frame to the ground is not more than 0.3%.
The assembly of the middle frame of the belt conveyor shall meet the following requirements:
(1) The reason for the deviation of the parallelism of the middle frame of the belt conveyor on the parallel plane of the plumb line should not exceed 0.1% of the length;
(2) The upper, lower, and height deviations of the seams of the middle frame of the belt conveyor should not exceed 1 mm;
(3) The error of the interval L of the middle frame of the belt conveyor should not exceed ±1.5mm, and the relative elevation difference should not exceed 0.2% of the interval;
(4) The reason for the deviation of the parallelism of the buffer idler roller across the center line to the vertical center line of the belt conveyor should not exceed 3 mm.

The position of the tensioning roller after the belt conveyor is connected, according to the way of the tensioning device, the material of the belt core, the length of the belt, and the braking system are clearly specified, and generally should meet the following requirements:
(1) For vertical or car-type tensioning devices, the forward loosening stroke should not be less than 400mm, and the rearward tightening stroke
It should be 1.5~5 times of the forward loosening stroke (when the length of the polyester, canvas belt core or belt conveyor exceeds 200m, and when the motor is started directly and there is a stroke braking system, the maximum tightening stroke should be selected ).
(2) For the spiral tensioning device of the belt conveyor, the forward loosening stroke should not be less than 100 mm.
(3) The scraper cleaning surface of the cleaning device should be in contact with the conveyor belt, and the contact length should not be less than 85% of the belt width.
After the idler roller is fixed on the belt conveyor frame, it should rotate flexibly and can be adjusted with washers. The axial cylindricity of the idler roller to its center line after installation: when the idler diameter D<800Mm, its dimensional tolerance is 0.60mm; when D>800Mm, its dimensional tolerance is 1.00mm. After the idler is fixed on the frame, the vertical dimension tolerance between its center line and the center line of the frame is 0.2%. The horizontal plane of the center of symmetry of the idler should overlap with the center line of the frame, and its symmetry dimension tolerance is 6 mm.