Storage Silos Tanks Heavy Fabrication – STORAGE SILOS & TANKS
Storage Silos Tanks Heavy Fabrication, an equipment used for long term or short term storage of dry items such as cement, food grains etc. or liquids such as water, chemicals etc. It is also used for blending (mixing) of multiple items in which case these are termed as Blending Silos.
Storage Silos Tanks Heavy Fabrication can have a very vast range of size starting from a few feet in diameter up to say 50 feet diameter and 100 feet or more of height. These are generally designed and fabricated out of mild steels in parts as per customer requirements in terms of capacity, type of material. Each fabrication is specifically engineered to withstand seismic forces, environmental changes, wind loads etc. Various international codes are followed for designing and fabrication of silos not only from a safety standpoint but also material strength. Various grades of steels as per national and international standards are used for silo fabrication. All plates and sections are of tested quality from well recognized suppliers including European suppliers.
Type of Equipment
Various international codes are followed for designing and fabrication of silos not only from a safety standpoint but also material strength. These specifications are used in conjunction with the following codes:
| AISC – American Institute of Steel Construction |
| AWS – American Welding Society |
| UBC – Uniform Building Code |
| FDA – Food and Drug Administration |
| OSHA – Occupational Safety and Health Administration |
| ASTM – American Society for Testing and Materials |
| SAE – Society of Automotive Engineers |
| SSPC – Steel Structures Painting Council |
Storage Silos Tanks Heavy Fabrication Design Criteria
While designing of silos some basic design criteria is kept in mind such as :
| Wind factor with combined height, exposure and gust factor coefficient is kept in mind. |
| Seismic zone/forces factor. |
| Combined live, dead, and roof loads are uniformly distributed, with all nozzles, manhole and filter locations designed accordingly. |
| Silo design is based on buckling strength of the body and supporting structure. |
| Silos are designed to atmospheric pressures. |
| The inlets and discharge gates/equipment are designed keeping in mind the load and fluidity of the material(s). |
| There are various other design criteria such as type of material, soil bearing capacity on full load, type of blending equipment (open air slides etc.) etc. which also have to be kept in mind. |
Manufacturing Specifications
| WELDING |
|
| SURFACE PREPARATION |
|
| COATINGS CARBON STEEL | Silo exterior is coated with minimum two coats rust preventive gray or red primer (of branded manufacturer) and finish epoxy or enamel paint as per requirement. |
Storage Silos Tanks Heavy Fabrication Materials Standards
Various grades of steels as per national and international standards are used for silo fabrication. All plates and sections are of tested quality from well recognized suppliers including European suppliers. Some of the common grades of steels used are :
| Steel plates as per IS 2062 Grade A/B/C, ASTM 569, SA 516, A36 etc. |
| Structural shaped/sections as per ASTM A36 |
| Structural pipes as per ASTM A53. |
| Handrails, ladders, cages and platforms are designed to meet OSHA requirements and are welded units to minimize field erection. |
| Rolling Capacity | Upto 100 mm Th x 3500mm L on 3 roller rolling machine |
| Welding Technique | Submerged metal Arc, MIG, TIG 2 mm to 8 mm electrodes |
| Welder Qualification | WPS Qualified (attested and approved by third party inspection agency) |
| Weld tests |
|
| Lifting Capacity |
|
| Dynamic Balancing | Up to 2500 mm diameter |
| Sand Blasting | Chamber size of 7000 mm x 7000 mm |
| Stress Relieving | Furnace size of 4000 mm x 8000 mm |