4 Causes Of Backups In Silo Operation and How To Prevent Them

4 Causes Of Backups In Silo Operation and How To Prevent Them

Silos are the backbone of your grain harvesting operation, but they’re also prone to backups due to the large amount of material that flows through them. A clogged silo can cost you a lot of money in lost time and damaged product, and backups also increase the risk of explosion, entrapment and other safety hazards. If your silo is constantly getting jammed, consider these four common causes of backups and learn how to prevent them.

4 Causes Of Backups In Silo Operation and How To Prevent Them

Narrow Discharge Outlet

The discharge outlet is the end of the line where all the material exits the silo. If this opening is too small for the type of product being processed, individual grains can clump together and block the outlet. Fortunately, the solution to this problem is easy. When your silo is empty, just make the outlet wider. Test it with a small amount of product to make sure the size is right before refilling.

Incorrect Discharge Angle

Size isn’t the only reason for jams at the discharge outlet. If the slope of the outlet is not adequately steep, materials will not flow through quickly enough to avoid a backup. However, an outlet that’s overly steep causes product to exit too fast, which can lead to damages and injuries. Test the slope of your outlet before filling your silo to prevent problems.


No, a rathole in your silo doesn’t mean you need to call pest control. A rathole refers to a partial blockage that forces product to flow through a narrow channel, reducing efficiency and creating a fire hazard from the friction. The most effective way to deal with ratholes is installing an air cannon to blast them out. You can choose a manually operated canon or an automatic one that senses blockages and removes them with little disruption in your operations.


Bridging in your silo is when product clumps together in an arch that restricts flow above it. Bridges mostly form near outlets and are common with small, fine materials like rice and wheat grains. Like ratholes, you can use air canons to break up bridges. If bridging is a pervasive problem in your operation, consider installing a vibration system to prevent the product from clumping together.

Remember, safety comes first when dealing with a silo backup. When entering a silo, steer clear of moving equipment and be careful to stay above the grain so you don’t become trapped or buried. Never walk on flowing grain because the suction can pull you under.