Bolted Steel Silo
Modular, Easy-Install
5–25,000 m³ Modular Storage Capacity | Wind Resistance up to 200 km/h | Z600 Heavy Galvanized Protection
What is Bolted Steel Silo Technology?
Bolted steel silo is a modular storage structure assembled on-site using factory-fabricated steel panels and high-strength bolts. As the excellent option for vertical storage of grain, powders, and bulk solids and industrial storage silo needs, bolted silos provide a highly efficient solution for the vertical storage of large handling capacity.
Core Engineering Principles
Neorigin Group designs the bolted silo systems around the following core principles of engineering.
- Panels are pre-formed and engineered to have a tight fit and are structurally accurate.
- Fitment is accomplished through CNC (Computer Numerical Control) and is guaranteed to be accurate.
- Custom orders are easily accommodated within a short time frame.
- Joints are made with high-strength bolts (Grade 8.8 and higher).
- Bolt arrangements provide additional stiffening and help distribute loads that are unbalanced.
- The system is modular and can be fully containerized for economic shipping.
- Assembly can be accomplished with minimal equipment as it is done ring-by-ring.
- Steel thickness is highly variable (4mm-10mm) depending on the design calculations and the loads the system is expected to perform under.
- Minimizing dead load reduces the cost of foundation construction.
Configurable Capacity & Layout Flexibility
Ideal for land-constrained facilities and brownfield plant upgrades, our silo storage systems are designed to meet your specific dimensions and capacity requirements.
- Storage capacity options include systems from several dozen tons to over 3,000 tons.
- Steel Silos with standard diameters from 3m to 40m.
- Integrated silo farm is available with multiple silos.
The benifits of Bolted Storage Silo
Different silo technologies have their own major differences. Before making a long term investment, you should know the differences and compare bolted silos with conventional ones. This comparison should include airtightness, construction, efficiency, durability, maintenance, and lifecycle cost.
DECISION GUIDE: Quick Selection
A silo systems are an incredibly important part of an infrastructure system. They directly influence the efficiency of material handling, the safety of operations, and the performance of the system as a whole throughout its lifecycle. If you make bad design decisions in this area, you are likely to recognize the real costs of these decisions for many years to come after the system has been commissioned.
Protection & Preservation
To protect the quality of your stored materials and the production stability, Neorigin Group always comes up with the most suitable coating configuration and superior sealing strategies.
ot-dip galvanizing or Aluzinc® coating with a typical service life of 20–30 years. Extra protection can be added for coastal or chemical environments.
Pre tensioned high strength bolting with elastic sealing gaskets and industrial sealants prevent leakage. For silos that store fine powders, a liner is provided.
Roof systems that are rainproof along with condensation control are designed to limit caking, spoilage and contamination.
- Panel Replaceability
Panels can be individually replaced.
- Capacity Upgrades
Parallel silos and stiffeners can be added along with advanced silos.
- Asset Relocation
Resell, move, or dismantle silo systems before end of designed life.
- Lower Downtime
Faster maintenance compared to welded or concrete silos.
Long-Term Operational Flexibility
Silo systems with a bolted design, versus a design with welded silos or concrete, are segmented which results in a lower long term maintenance cost. This also results in a higher value of the asset beyond the designed life.
Fully bolted construction enables single-panel inspection, replacement, and maintenance without dangerous welding operations, reducing operational disruption during repairs."
Technical Performance Comparison
| Parameter | Spiral Silo (Lipp) | Bolted Steel | Welded Steel | Concrete |
|---|---|---|---|---|
| Typical Capacity (per silo) | 500 – 25,000 t Small to Medium focus | 10 – 3,000+ t Widest range | 1,000 – 100,000 t Ultra-large | 10,000 – 50,000+ t Large focus |
| On-site Construction Time (per silo) | 3–15 Days Fastest | 10-20 Days Fast | 30–60 Days Slow | ＞120 Days Slowest |
| Airtightness Performance | Excellent Long-Term Airtightness Mech. 5-layer seam | Moderate Bolts + EPDM (needs maint.) | Very High (Depends on weld quality) | Variable Prone to cracking |
| Service Life | 25 Years | 25 Years | 25 Years | 50 Years |
| Typical Foundation Cost (% of total project cost) | 10 – 15% Lightweight | 10 – 15% | 20 – 30% | 30 – 40% Excessive dead weight raises foundation construction costs |
| Maintenance Cost (% of annual operating costs) | 0.5% | 5% | 5% | 0.5% |
| Typical Construction Method | On-site continuous forming (Highly Automated) | Factory prefab, modular assembly | Site welding (Labor intensive) | Formwork casting (High civil construction workload) |
Structure Design
A bolted steel silo is more than simply a “panelized tank.”
— its performance depends on bolt preload, panel geometry, stiffeners, sealing, and load-path continuity.
A balanced design and a variety of engineering considerations is required to achieve long-term reliability and optimal performance. This may include consideration of temperature changes, corrosion, and wind.
Key Technical Parameters
3 – 40 m (up to 40m special)
Advanced Material Selection
Strong and corrosion resistant steel is used in silo walls to achieve durability and reliability. Coating and base steel must be chosen properly and correlated to the conditions of the stored material and silo wall corrosion.
Core Structural Steel Options
Carbon Steel
- Q235 / S235 / ASTM A36 (Standard Strength)
- Q345 / S355 / ASTM A572 (High Strength)
Anti-Corrosion Coating Systems
Galvanized Steel Silo
The industry standard for general bulk storage.
ZAM Steel (Zinc-Aluminum-Magnesium)
An advanced high corrosion resistant coating which has the ability to autogenic heal at cut edges.
Material & Industry Suitability
Our versatile spiral silos are deployed across diverse sectors, handling a vast array of powders, granules, and aggregates.
- Cement
- Aggregates
- Fly Ash
- Ground Granulated Blast Furnace Slag / GGBFS
- Manufactured Sand
- Gypsum
- Stone Powder
- Lime
- Slag
- Carbide Slag
- Foamed Glass Aggregate
- Anti-Segregation Agent
- Concrete Residue Treatment Agent
- River Sand
- Crushed Stone
- Calcite
- Silica Fume
- Autoclaved Silicate Aggregate
- Wheat
- Corn
- Paddy Rice
- Sorghum
- Beans
- Rice Husk
- Flour
- Feed
- Liquid Fats And Oils
- Soybean Meal
- Oilseeds
- Soybean
- Rapeseed
- Sunflower Seeds
- Peanut
- Cottonseed
- Corn Germ
- Palm Kernel
- Flaxseed
- Ferroalloy
- Alumina
- Copper Concentrate
- Lead-Zinc Concentrate
- Quartz Sand
- Sulfur Concentrate
- Iron Ore Fines
- Sinter
- Active Calcium Oxide
- Metallurgical Dust
- Magnesite
- Magnesium Oxide
- Petroleum Coke
- Needle Coke
- Graphitized Coke
- Graphite
- Food Waste
- Orange Peel Fiber
- Construction Waste
- Recycled Aggregate
- Sludge
- Biomass Wastes
- Fly Ash
- Furnace Slag
- Fgd Gypsum
- Ceramsite
- Fly Ash
- Urea
- Soda Ash
- Polyethylene Pellets
- Plastic Pellets
- Semi-Coke
- Carbon Black
- Coke Dry Quenching
- Petroleum Coke
- Calcined Petroleum Coke (CPC)
- Prebaked Anode
- Coal
- Iron Concentrate
- Phosphate Rock Powder
- Silica Sand
- Kaolin
- Limestone
- Silicate Rock
- Barite Powder
- Dolomite
- Attapulgite Clay
Trusted by Industry Leaders
Endorsed by engineers, operators, and procurement personnel for long-term industrial storage projects.
The true test for silos is smooth discharge, perfect sealing, and wear resistance. In practice, the Neorigin silo system has met all our engineering expectations. It operates in a highly reliable long-term state."
Storage of grain is not just about the outer shell. Grain is not just a static material; it is alive and needs to breathe. Neorigin silos, with their excellent ventilation design, maintain the necessary breathing and humidity balance that is required in the storage of grain."
Purchasing equipment is not where the world ends. It is about sustained assurance of operation a decade later. From the information we have, their structural stability and long-term maintainability meets our safety requirements."
I am looking for the assurance of long-term operational reliability rather than short-term assurance. The Neorigin bulk storage system offers reliable operation, and the supplier was a true project partner during the whole process."
Frequently Asked Questions
What is the maximum storage capacity of a bolted silo
Compared to spiral silos, bolted silos are essentially unlimited in how large they can be. Bolted silos can be designed to have capacities that range from a couple thousand cubic meters (for silos designed to store industrial materials) to several tens of thousands of cubic meters (for silo systems designed to store large quantities of bulk materials).
The modular design of the steel panels allows for both horizontal (through the addition of more silos) and vertical (adding more rings) expansion.
This flexibility is very advantageous to bolted steel silos, especially for projects with phased investments when the initial demand for storage can be very different from the anticipated future demand for storage.
After a bolted silo is constructed, can it be expanded or relocated?
Absolutely, this is one of the biggest advantages of bolted silos.
Bolted silos can be completely disassembled and relocated. Panels are de-bolted, inspected, re-treated if necessary, packed into ISO standard containers, and re-erected.
Bolted silos can also be increased in height by simply adding additional rings. The entire kit for a bolted silo can be shipped in a compact configuration for sea freight.
For projects that have uncertain permanence, phased capacity, or flexible multi-site deployments, this reversibility means bolted silos convert capital costs from a sunk cost to a transferable asset.
How does maintenance work on a bolted steel silo?
Maintenance is very easy on a bolted silo and is designed to be easily done by non-specialists.
Routine maintenance simply requires that bolts, washers, and vents are checked monthly, and that wall deformation and weld seams are checked twice a year.
Impairments from impact, corrosion, or abrasion to a panel means that said panel must simply be bolted away and an identical new panel replaced, often referred to as a “surgical replacement.”
There is no need for cutting, welding, or structural re-certification.
This type of maintenance is very different from the maintenance model of Spiral silos, wherein any localized wall repair would on-site require cutting and the re-welding of a wall, certified welders, and possibly a structural re-certification.
What steel grades and galvanization standards should I specify for a bolted silo in a coastal environment?
For all inland environments S350GD with Z275 (275 g/m²) panels are specified.
For coastal or tropical environments S350GD or S450GD with Z600 (600 g/m²) are the minimum requirements.
For the ISO 12944 corrosivity category of C5-M (marine) or CX (high offshore exposure) will require ZM310 Zinc-Magnesium with a high obliging epoxy primer, and for all severe environments, Symaga employs ZM310.
For the very large diameter, high load silos located at port terminals, S450GD, panel strength and corrosion resistance, are also provided.
When it comes to corrosion protection, always submit for a project-based specification, as brochure data will not be sufficient.
How long does it take to install a bolted silo, and what affects the timeline?
The main structural assembly of a 1,000-tonne bolted silo comes in a range of 10 to 20 days.
Key variables impacting the timeline include crew size and experience, the availability of access roads and cranes, the readiness of foundations, weather, and whether the installation is a first-time or repeated erection.
Repeated erections are done more quickly because the crew has pre-sorted the panels.
EPC milestone schedules should account for additional time for foundation curing and the time it takes to commission the equipment.
What design standards govern bolted silo structural engineering?
The design of bolted steel silos incorporates EN 1993-4-1 (Design of steel structures — Silos) and EN 1991-4 (Actions on structures — Silos and tanks), including shell buckling and resistance to forces of bulk structures and eccentric discharge.
For port terminal installations, wind load studies are conducted in accordance with EN 1991-1-4 and Terrain Category 0 (open sea exposure).
For projects in North America, grain pressure is determined in accordance with ANSI/ASAE S433.1.
For cement and other industrial applications, design and construction of silos is governed by ACI 313-16, which incorporates pressure and thermal loading, as well as asymmetric discharge.
What features of a bolted silo address bridging and ratholing when storing cement?
Cement is particularly prone to bridging and ratholing under discharge conditions considered low velocity if the bulk density is in the range of 1.5-1.6 t/m³.
A sufficient design of a bolted silo to address these conditions considers:
Mass flow hopper design incorporating steep cone angles (typically > 60° from horizontal) to ensure first-in-first-out flow of material and comply with ACI 313-16.
Aeration (fluidization) pads along the slopes of the hopper to release bridging by cohesive arching.
Discharge design with a symmetric flow pattern to ensure no asymmetric loading of the walls of the silo occurs.
Bolted construction fits well in this example because it allows the individual panel that experiences accelerated localized wear to be replaced without shutting the silo down.