As the name suggests, Storage Silos are the storage equipments, which are used for the storage of dry items such as food grains, cement, and liquids such as chemicals, water etc. etc. Used for the long term or short term these are also known for their blending (mixing) of multiple items in which case these are named as Blending Silos. These can have a vast ambit of size opening from a few feet in diameter up to say 50 feet diameter and 100 feet or more of height. These are commonly designed and fabricated out of mild steels in surroundings as per customer demands in terms of capacity and type of material. Every single silo is specifically engineered to stand firm in environmental changes, seismic forces, wind loads etc. Welded silos of the Storage Silos' range can be made-up by utilizing leg, skirt or structural assistance.
Different international codes are followed for designing and manufacturing of silos not only from the safety point of view but also for material strength. These specifications are utilized in conjunction with the following codifications:
AISC - American Institute of Steel Construction
UBC -Uniform Building Code
AWS - American Welding Society
FDA - Food and Drug Administration
ASTM - American Society for Testing and Materials
SAE - Society of Automotive Engineers
OSHA - Occupational Safety and Health Administration
SSPC - Steel Structures Painting Council
While the designing process of silos, some primary design criteria are considered like:
Wind factor with consolidated height, vulnerability and gust factor coefficient is also considered.
Seismic zone/powers factor.
Cooperative live, dead, and roof loads are consistently dealt out, with all manholes, nozzles and filter positions that are accordingly designed.
Silo designs are based on buckling posture of the body as well as on supporting construction.
Silos are planned to bear atmospheric pressures.
The discharge gates/equipments, inlets are configured on the basis of load and liquidity of the material(s).
There are assorted other design criteria such as kind of blending equipment (open air slides etc.), type of material, soil bearing capability on full load etc.
When particularized, all structural welding shall adapt to WPS regulations.
Shell seams shall have correct incursion using grade-appropriate welding wire with automated MIG or SAW welding instrumentality.
All weld surfaces with distinct and sharp boundaries are ground, the undercuts are fixed, mended and re-ground. All weld spatter is abstracted and outside surfaces are grit or sand blasted as per the demand.
Coatings Carbon Steel
Different grades of steels as per national as well as international standards are utilized for silo fabrication. All sections and plates are of proven quality from well acknowledged suppliers including European suppliers. Few of the common grades of steels utilized are-
Steel plates as per IS 2062 Grade A/B/C, SA 516, A36, ASTM 569 etc.
Functional shaped/sections as per ASTM A36
Functional pipes as per ASTM A53.
Ladders, cages, handrails, and platforms are planned to meet OSHA duties and are welded units to decrease field erection.
Up to 100 mm Th x 3500mm L on 3 roller rolling device.
Swamped metal Arc, MIG, TIG 2 mm to 8 mm electrodes.
WPS Qualified (authenticated and authorized by third party inspection agency)
100% on weld conjuncts
Up to 2500 mm diameter
Chamber size of 7000 mm x 7000 mm
Furnace size of 4000 mm x 8000 mm