Load cells are available in a variety of shapes, sizes and capacities and are now the industry standard for all types of weighing. This can be a bit of a minefield trying to find the correct load cell for your application. I have listed some of the most commonly found today and their uses.
Single Point – Single point is probably the cheapest and most popular type on the market today. Because of their price and reliability, they can be found in most types of retail scales, weighing scales, medical scales, parcel scales, and postal scales. This type of load cell can also be used in platform scales and industrial weighing systems to provide accurate readings regardless of the position of the load on the platform, reducing manufacturing costs.
Tube type – The tube type has been around for a long time and is likely to become the industry standard for most high capacity compression applications. Tube type load cells are used for single and multi weighing applications. This type of cell has buttons on the top and bottom sides and can only be used in compression. Tube-type load cells are used in tank scales, ship weighing applications, axle scales, truck scales, vehicle scales and weighbridges. Tube type load cells offer accurate weighing in harsh environments.
Double Ended Shear Beams – For medium to high capacity applications, double ended shear beams offer a number of advantages over other designs. This type has the ability to sway on the stand to accommodate misalignments in the mounting surface while still being maintained, it also allows limited movement to allow thermal expansion and contraction as well as lifting protection. This cell type is also available as a weighing module kit.
Single End Shear Beams – Single ended shear beams are commonly found in all types of floor, platform and shipping scales today and provide the ideal solution for most medium capacity weighing applications. The single end shear cell has the ability to withstand full capacity side loads without any problems which makes it particularly suitable for weighing systems with mixers, blenders and agitators. This type is very durable but can be expensive and impractical to install above 10,000 kg. This cell type is also available as a weighing module.
Tension Links – Tension links are suitable for applications such as winching, hanging scales, crane scales and lifting systems. This type of load cell offers superior accuracy in high capacity weighing. This type of cell has openings at both ends for easy connection to shackles, wire ropes, D links, or other rigging. Tension link load cells provide a robust design for resistance to side loading.
Torque Rings – Torque rings are a relatively new design concept and provide an excellent low profile solution for a wide range of weighing applications. Unlike standard compression load cells, which can easily suffer from off-axis loading problems, the torsion ring is loaded via an annular ring located in the middle. By using a central float pin to transmit the load to this ring, optimal load recognition is ensured and off-axis loads of up to three or four degrees can be tolerated without loss of performance. Exclusive mounting modules, which offer great versatility, are now available for process weighing and platform weighing applications.
Weighing Modules – Weighing modules generally consist of load cells with mounting kits. Many types now come supplied as modules but generally single or double shear beam and tube types are the industry standard. Load cell weighing modules are used in tank scales, silo weighing, ship weighing applications, axle scales, truck scales, vehicle scales and weighbridges.
Wireless – All of the above has one major drawback; they are connected to the device via a cable. One of the main problems with weighbridges or floor scales is the possibility of damaged cables. Using the latest technology, wireless, load cells are now available and could one day become the industry standard. All of the above load cells are now available in wireless format, although this technology is very expensive.
Type S – Type S gets their name from their shape, being the letter ‘S’. S type load cells can provide digital output when used in either tension or compression and provide superior side load rejection. This type of cell has two female threaded mounting points, the top and bottom are where eye bolts or threaded rod ends can be attached. This type is used in crane scales, hanging scales, hoist scales, and most tension applications.