What Silo Should I Buy?

New or used? Size and material?

If you’re doing sums on how much a silo will cost, what money it could save you operationally, and what size and format is best, read on to find out more.

Peveril Machinery manufacture new silos and on occasion have used silos available. We supply and install silos from 10 ton capacity to 200 ton across the UK, mainly for on-site storage of cement or other bulk mineral product.

Recent silo installations have included a 60 ton capacity, second-hand cement which cost £40,000 plus delivery and installation compared to a brand-new 60 ton capacity silo, engineered specially for the client’s needs for £70,00, including installation, electrical controls and some extra accessories.

Silo size – do you need a 30, 40, 50 ton or larger?

Silo size is a good place to start narrowing your field of search.

For bulk storage of heavier mineral powders such as cement, a 36m³ silo is probably the smallest you’ll want. Below this, and you’re going to miss out on the main value of having a silo in the first place; bulk priced deliveries of full tanker loads. A larger silo than this allows you to go down to a couple of tons before being replenished with a full truck load, providing your production a buffer from delayed deliveries. Larger capacity silos will allow you a lot more flexibility to meet supply and demand fluctuations.

Don’t forget that when being freshly delivered into the silo, powders have a greater volume than when they’re settled down. This is especially noticeable with silos at the 30-35 ton capacity and tends to cause operational challenges.

It is important that silos are not over-filled as this can cause ‘blinding’ of the air-vent dust filter, which serves as an important protection against over-pressurisation. A 40m³ silo will hold approximately 56 tons of dry cement.

Which is best, a low-level silo or a vertical silo (tall upright) one?

Silos come in two broad types, low-level and upright. Low-level silos can often cost less to install but have a higher running cost as they have two screw conveyors to operate them. Large silos tend to be made upright to save on yard space.

Check for head height, access and powerlines before ordering your upright silo. They will require a large crane, especially if there is also a distance from the truck or obstacles to cover.

Factors that can make a cost difference

Having just discussed the pros and cons of vertical and horizontal silos, including installation costs, let’s look at some of the other factors of purchasing new versus second-hand.

A shell-only silo can look very inexpensive at first sight, especially if it’s a used one which has yet to be cleaned out and dismantled. You might benefit from being able to see the components and material handling side of it at work, providing some reassurance of what you’re buying, however, repair work, such as replacing corroded steelwork, might not be found until you dismantle it for moving.

Transport is clearly a big factor in buying a silo and the location and ease of access of both pick-up and delivery site is key. While there is an availability of silos from continental Europe, the cost of import is increased by the sea-freight/ferry crossing, customs documentation, and import duty, and they are often not built to British Standards.

Assuming that the silo is a quality used one, or brand new, the accessories you need for your plant operations are the next biggest factor to consider.

Be aware of exactly what you need to make the silo an efficient addition to your production-flow. Can you utilise existing material handling equipment and consider if the installation of a new silo creates opportunity to improve your layout and processes sitewide. Networking and consulting with industry partners can really help you here. We at Peveril are always happy for an informal consultation and to share our experience.

Silo material and finish

UK silos for cement are most often made from 5mm steel plate or thicker and painted with an industrial coating. You will find that European built silos are mostly 3mm or 4mm thick supported with an external rolled channel to get the required structural strength.

The dispensing cone is often made from thicker steel, while the top cover may be thinner than the walls to reduce weight and cost.

The frame that it stands on should be made with robust steel legs which are most often galvanised to resist rust and corrosion. It is important to inspect your silos periodically and keep them maintained.

Is a silo really worth it?

To help you decide whether a silo is right for your situation, consider your options. Alternatives to on-site silos are bulk bag unloaders - 25kg bags which can be dispensed into a functional material handling system via a bag breaker, or just measuring out manually from a bulk bag.

Significant savings can be made by purchasing in bulk and reducing the trip frequency and mileage of trucks. Whether these are your trucks or your suppliers, the total embodied financial and carbon cost of a project is increasingly considered from start to finish of the supply chain.

Having a rough figure for the end-of-project silo residual value can also help, something a silo supplier like Peveril can discuss with you.

Buying a more expensive, new silo will cost more upfront, but would likely mean you have something easier to sell on when no longer needed. A low-quality, cheap silo may not last you long enough to justify your installation costs or bring surprise costs down the line in repair and downtime. That said, a low-cost silo could be all you need to get your project going until an upgrade makes financial sense.

Conclusion

It can be very handy to have a rough figure of what a silo costs at the earliest stages of consideration. Knowing what makes such a difference to the cost will help you maximise your investment and return.

Silos bring significant advantages to sites handling bulk dry minerals such as sand, cement or lime etc. Control of material inventory, secure dry storage, bulk purchasing power, reduced manual handling and dust issues and a lower carbon footprint through reduction in transport mileage.

There are many different requirements for silo storage and a number of ways of meeting these. Calculating your payback and involving knowledgeable, experienced industry partners helps reduce risk and increases profitability and project viability.
You can speak to us at Peveril Machinery about your new silo needs for free. Contact us on 0115 930 9068 or email [email protected].