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Saturday March 21 2020


The design and type of vessel impacts the number of bolt-on sensors and the specific placement of them. The quantity and placement of each sensor is important in order to get the most accurate and consistent measurements.

Bolt-on sensors can only be used on metal supports and should always be installed in pairs. By having two sensors on the same support, the changes in the vessel due to natural bending of the metal structure are canceled out and a true reading of the weight is given.

We’ll go over the 3 most prominent types of vessels. Please remember that this is just a guide and that sensors are only one part of the whole weighing system. For a more comprehensive explanation, download the complete Bolt-on Sensor Quantity & Placement Guidelines at the bottom of this page. Remember that you can always use our Product Selector to help you chose the best solution for your application.

1. Legged Vessels

Legged vessels, one of the most common types of silos, are simply held up by a leg structure. The primary factor in separating legged vessels into different groups in the number of braces between the legs or supports. A brace is designed to make the structure stronger and more sturdy, usually being able to hold more weight.


If there are no braces between the supports, there are no additional factors to consider in determining mounting location of the sensors. Therefore, the number of legs determines the number of sensor pairs that would be required; two sensors per leg. For example, a four legged silo would need 8 bolt-on sensors (4 pairs).


If the vessel structure includes single or dual levels of bracing supports, it will be important to learn more about the structure to determine where and how many bolt-on sensors will be the most effective. For more than two layers of bracing, please contact us for further assistance.

If there are no braces, there are no additional factors to consider in determining the number and mounting location of sensors. If the vessel structure does include one or multiple layers of bracing supports, more information will need to be known to determine where and how many bolt-on sensors will be the most effective.

Questions that may be asked to identify the optimal number of sensors and placement on vessels with braces:

  • What is the size of the cross brace?
  • Where are the cross braces connected to the vessel or each other
  • How are the cross braces connected – welded, bolted, etc
An example of a silo with leg bracing.

2. Horizontal Beam or Shear Vessels

If a vessel is supported by horizontal beams which are connected to vertical legs, it is considered a horizontal beam or a shear application. The weight forces of the vessel are distributed to the horizontal beams. The horizontal beam connection to a vertical leg creates the shear force, which is what is being measured by the sensor to determine the weight of the material. The number of support points for each vessel is essential to determine the number and location of sensors used.

3. Skirted Silos

Skirted silos have a weight bearing metal wall or ‘skirt’ around the material container. Skirted silos can either be welded or bolted together – however, the construction type does impact the placement of the sensor pairs. The sensors need to be placed around the silo that is balanced for consistent measurements.