1. Generally, the diameter of the depression part of the high rod lamp is selected as the bottom diameter+ 100-150; if the bottom diameter of the lamp column is 500, the diameter of the depression part should be 600-650.

2. The height is one -tenth of the light rod, for example, the height of the depression part of the 25M light rod is 2.5m.

3. The depth of excavation is one in seventh of the light rod. For example, the excavation of a 25 -meter -long lamp rod is about 3.5 meters (less than 15 meters, and the calculation is based on one -eighth to one -nineths)

4. The excavation width is usually 3-4 times the standard of concave parts. For example, the excavation width of the concave part with diameter 700 should be 2100 (depending on the weight and height of the light pole) 15 meters or shorter, usually 2-3 times.

5. Generally, the concave components growing more than 15 meters should be equipped with decorative flange to prevent deformation of the concave part. Usually, the thickness of 6-8 cm is enough. The center has a 150-200 faucet that can pass through the pipeline. The standard of decorative flanges is the same as the standard of the chassis.