Briefly describe what are the installation requirements for the support rings of tower internals?

The most important thing is to ensure levelness, as specified in the standards.

During the installation of the tower internals, there are no specific requirements regarding the distance between the support ring and the shell seam. If the support ring is installed on the seam, it generally has no adverse effects; however, it is advisable to avoid placing it over the welds. The installation dimensions of the internals and other requirements must be followed strictly in accordance with the provided drawings and technical documents. The general requirements are as follows: 1) Before installing the support plate, it is necessary to ensure that the support lugs and support rings are at the correct elevation ； 2) Install the support plate from the outside toward the center according to the relevant drawings ； 3) Do not stand on the support plate; use wooden walkways to distribute the weight ； 4) All bolts are secured with double nuts and titanium wire ； 5) The support plate should be installed firmly and stably ； 6) The channel aperture and hole spacing of the support plate shall meet the design requirements, and the holes must not be blocked ； 7) After the support ring is welded to the tower wall, the local levelness deviation of its upper surface over a chord length of 300 mm shall not exceed 1 mm. The allowable levelness deviation for the entire upper surface of the support ring is specified in the table below: Inner diameter of the tower Allowable deviation (mm) D