Tension Link Load Cells, also known as Tension Links, are a critical system component for ensuring an overload does not happen on cranes and other types of working machines designed to lift and move heavy loads. Cranes are sturdy machines, but they all have a limit on the weight they can safely lift. Overloading is not only damaging to the equipment but can also be dangerous for employees in the workplace or work site.

Cranes are very common at construction sites, oil and gas facilities, shipyards, HVAC installations, and many other industrial locations. They hoist and move thousands of pounds at a time and save countless hours of work for the personnel working alongside them. A crane’s lifting capacity, however, is not unlimited as they are designed for a specific working range. If that capacity is exceeded, the machine can weaken, bend, tip over, and even collapse, putting the people, property, and project at risk.

For crane applications, Tension Links can measure the weight lifted, ensure the weight is within the designed operating range, and can also be integrated into a system to potentially stop and/or record an overload event.

How Do Strainsert Tension Link Load Cells Work?

The tension link sensing element consists of a strain gage bridge circuit internally installed in a small hole along the neutral longitudinal axis of the sensor body. This unique and patented arrangement provides a most effective means for accurate load measurement, while mitigating the adverse measurement effects of extraneous torsional and bending loads. The internal gaging protects and seals the internal electronics for stay-on-the-job ruggedness.

A strain gauge is made of very thin wire or foil arranged in a grid pattern. These metal components experience a change in electrical resistance when their shape is deformed. An amplifier, with voltage or current output, is calibrated to produce a known output with the change in weight/force. In a balanced state, the reading in the strain gauge bridge circuit will be zero. In the presence of a load, the strain gauge stretches, causing an increase in electrical resistance that leads to a corresponding change in known output. This change is used to determine the tensile force in the sensor, and in this case, the weight lifted.

Additional Advantages of Tension Links

Tension links can be adapted to installations using common rigging equipment, such as shackles, clevises, or threaded connections. Therefore, retrofits are typically not required. A simple in-line installation can be made, for example, between a dead end/pad eye and the end of a cable where a user wants to measure tension.

Custom design options for specific dimensions, ratings, and capacities are available. These options provide additional value, especially for difficult applications or harsh environments. Tension Links can also be customized for underwater use, while providing accuracy, repeatability, and durability in a high-pressure environment.

Another customization option includes wireless telemetry for cases where cabling is neither practical nor cost effective, such as below the hook on a crane. This allows for a wider range of applications, quicker installation, durability, and reliable measurement readings.

Please contact Strainsert for any of your Tension Link application needs or to discuss the many other types of Standard and Custom Force Sensors we design and manufacture. We look forward to working with you.