Advantages & Applications
Safe-Quick-Easy-Economical
Safety :
Hydraulic tank jacking is proven and safest way to construct storage tanks.
This method as replaced by old tradional method of using all cranes and
scaffoldings.
By using hydraulic tank jacking all the work is done a ground level and hence
no accidents.
Faster Completion :
During errection/fabrication, shell plates are placed at the ground instead
of higher level, hence saving time and adhering to safety.
By adopting tank jacking method, construction can be done during rainy
season,since construction is done inside the tank and with the protection of
tank shell plates.
Ease Of Operations :
Since the welding is done almost ground level,safety of the workers and
also inspectors can inspect the quality of the weld at the ground level
instead of climbing on heights and carrying out inspection of weld joints
etc.
Economical :
No cranes, no scaffolding,less man power,quicker.
cost of jacking equipment is recovered r cructing 4-5 tanks .
Tank Erection Top Downwards Cuts
Construction Time And Cost Considerably :
New shell plates are constructed at ground level
instead of being hauled up to about 30 feet heights or more, saving
considerable time required for alignment of plates. The cumulative time
required for lifting of men and material to heights is eliminated. Tank
construction work remains practically unaffected by rain or snow, since most
work is performed under the protection of the tank itself.
- Most of the fabrication work is performed at ground level allowing
for faster erection and reducing the risk of possible injuries
- Eliminates the requirement of the crane
- Faster erection
- Cost of jacking equipment can be easily recovered after construction
of 3 to 4 storage tanks or by erecting about 1200 tons of tankage.
Jacking cost is approximately USD 50 per ton for 1200 tons
Example : Tank of 30 m diameter weighing about 300 tons needs 30
jacks of 12 ton each. Full cost of jacking equipment can be recovered in 4
such tanks.
Working Capacity
(metric tons) |
12 |
25 |
Testing load (metric tons) |
18 |
37.5 |
Standard arc
distance between jacks (m) |
1.80 to 3.0
|
Max plate height
for which jacking equipment can be supplied (m) |
2.5 or 3.0 or
more |
Min plate height
that can be used (m) |
1.40 |
Min safe bearing
capacity below trestle base plate (N/mm2) |
1.45 |
Plate thickness
range (mm) |
6 - 40 |
8 and above |
Unitary climb
(cm/stroke) |
10 |
Time per stroke
(minutes) |
Approx 5 |
Working pressure
(kg/cm2) |
120 |
135 |
Retracting system |
spring |
hydraulic |
Highlights
- Jacking equipment is supplied with singe jack lifting capacities of
8 tons
12 tons
25 tons
- Standard jacking equipment can be used for minimum shell plate width
(height) of 1400 mm. and maximum of 2500 mm
- For shell plates of more than 2500 width (height), jacking equipment
can be supplied against specific requirements
- Storage tanks with different types of roof (floating roof, fixed
roof, suspended deck roof, column supported roof)
- Gasholder tanks Horton spheres or spherical tanks for storage of
propane, ammonia in gaseous form
- Cryogenic tanks for storage of propane, ammonia at cryogenic
temperatures
Dimensions of some tanks that have been actually erected using jacking
equipment are:
- Smallest diameter of tank erected using jacking equipment : 6 mtrs*
- Largest diameter of tank erected using jacking equipment : 92 mtrs*
- Maximum weight of tank erected using jacking equipment : 1900 tons*
Applications :
- Building of field erected storage tanks
- Increasing tank capacity by adding shell rings or courses
- Dismantling of old tanks
- Repair or replacement of tank bottom plate
- Repair to tank foundation
- Erection of other circular structures such as reactor shields in
nuclear power stations, etc