21. The viaduct has 92 spans, each with internal diameter of 7.2 m. 22. The cast-iron tunnel is long, deep and has an internal diameter of about. 23. The tower is a concrete structure with an internal diameter of and a wall thickness of. 24. In 1998, the three aqueducts were replaced with one large aqueduct with a internal diameter . 25. This compressive loading fuses the circumferential fissures and sets the initial internal diameter and OD values. 26. The combination reamer is precision ground into a pattern that resembles the part s multiple internal diameters . 27. The pumped storage power station consists of two circular concrete silos, each of about internal diameter . 28. Kiln size is typically long / internal diameter , with a rotation speed of around 1 rpm. 29. The circular domed auditorium is 55 meters high and its internal diameter is 46.33 meters. 30. At the base of the brick wall is a small drainpipe with an internal diameter of 50mm.
