Galbiati Group has recently designed and built two segment erectors with a maximum capacity of 4.5 tons, intended for a Tunnel Boring Machine that will be used for an important excavating project in the Qingdao subway in China.
The two segment positioning erectors are made up of a fixed structure and a moving one, both made of electro-welded structural metalwork, flattened and machined on machine tools. The fixed part consists of two longitudinal beams on which the sliding guides, made of wear-resistant material, are mounted. The moving part, instead, comprises the translating, rotating ring and the pick-up unit.
The function of the two TBM erectors is to hook, lift and position the concrete segments to make the tunnel supporting structure.
The main movements of the two erectors consist of:
- an axial translation of the moving part;
- a rotation of the rotating ring and of the pick-up unit along the translation axis;
- a radial translation of the pick-up unit only.
The mounted erectors have each a maximum diameter of 4,100 mm, a maximum segment bearing capacity of about 4,500 Kg and a total weight of about 24,000 Kg and are also provided with a mounting plate equipped with a bolting machine.
The two erectors in question are equipped with a mechanical segment pick-up unit. The pick-up unit has the task of grasping and maintaining the segments for the entire duration of the positioning operations with three independent movements:
- Tilting = ± 5°
- Pitching = ± 5°
- Rolling = ± 5°
Erector technical data:
- Total beam length = 7,000 mm
- Total rotation = ± 220°
- Translation speed = N/A
- Rotational speed = max. 2 rpm
- Maximum load capacity = 4,500 kg (segment)
- Total weight = 24,000 Kg
- Intrados diameter = 5,400 mm
Some photos taken during the erectors assembling at our workshops are shown below.