In order to reduce as much as possible the loads acting on the final concrete structure and decrease at maximum the loads for launching, the design of rollers with rolling bearing it has been considered.
Moreover, the following advantage is reached using this typology of bearings:
- assure the safety of the operation;
- avoid possible interruption of the activity due to the changing of the sliders itself damaged by consumption.
ROLLERS
Models examples:
MR250T 2N 315D 45CM 2X-e
MR250T 2N 450D 45CM 2X-e
MR250T 2N 315D 30CM 120L 15S2X-e
MR250T 2N 450D 30CM 120L 15S2X-e
MR250T 2N 450D 45CM 120L 15S2X-e
Hereby is reported the legend for the rollers nomenclature:
| 1 | T | loading bearing capacity SLS [t] for each line |
| 2 | N | wheel number for single line of roller |
| 3 | D | nominal wheel diameter evaluated on rolling plane [mm] |
| 4 | CM | maximum vertical stroke [cm] |
| 5 | L | transversal translation option [cm] |
| 6 | S | rotation around vertical axis (slewing) option [DEG°] |
| 7 | 2X | double (roller on two parallel lines) |
| -e | Indicating bigger gorge |
ROLLERS - Models examples:
MR-250T-2N-315D-30CM-120L-15S2X-e
Rollers with:
• loading bearing capacity SLS [t] for each line 250t
• 2 single line of roller
• D315mm diameter
• 300 mm maximum vertical stroke
• 1200 mm transversal translation option
• 12° rotation around vertical axis
• double (roller on two parallel lines)
• bigger gorge
MR3000T24N450D120CM120L9S-e
Reason for design: the double deck bridge is a viaduct which the weight for linear meter exceeds the 20 ton/lm.
In this evidence the loads during launching operation are very considerable, in respect of it, 3000 tons capacity (at SLU) of the roller is required.
Roller Description:
24 wheels roller equipped with a rolling bearing. Wheels with 450 mm diameter and 275 mm gorge width. The wheels are in 6 groups of 4 wheels each.
Rollers have been designed with the following degree of freedom:
• Possibility to adjust the vertical position of the main body roller by use of
hydraulic jacks in order to assure the theory reaction on the roller.
• Possibility to rotate around the vertical axis of the main body roller by use of
hydraulic jacks, in order to follow the configuration of the web of the bottom
chord of the viaduct.
• Possibility to move transversally to the launching direction, by use of hydraulic
jacks in order to adjust the position of the roller according to the launching path.
Moreover, for the same reasons each of the 6 group of 4 wheels has:
• The possibility to adjust the vertical position by use of hydraulic jacks.
• The possibility to rotate around the vertical axis of each group by use of hydraulic
jacks.
• The possibility to move transversally to the launching direction by use of hydraulic
jacks.
In resume the 3000 tons capacity are equipped with the following hydraulic
component.
• Pos_1: jacks with 520 tons capacity and 61 cm jack stroke
• Pos_2: jacks with 800 tons capacity and 60 cm jack stroke
• Pos_3: jacks with 140 tons capacity and 33 cm jack stroke
• Pos_4: jacks with 440 tons capacity and 120 cm jack stroke
• Pos_5: jacks with 323 tons capacity and 75 cm jack stroke
MR3000T24N450D120CM120L9S-e
Reason for design: in order to reduce as much as possible the loads acting on the final concrete structure and decrease at maximum the loads for launching, the design of rollers with rolling bearing it has been considered.
Moreover the following advantage are reached using this typology of bearings:
- assure the safety of the operation;
- avoid possible interruption of the activity due to the changings of the sliders itself damaged by consumption.
LMV S.p.A.