Donut Load Cell By Shivay Sensor

A donut load cell, also known as a thru-hole load cell or load washer, is a specialized force sensor characterized by its annular (ring) shape with a central opening. This unique design allows a bolt, rod, or shaft to pass directly through its center, making it ideal for measuring compressive or tensile forces applied along the axis of that element.

How They Work

Like most load cells, donut load cells typically utilize strain gauge technology. Strain gauges are precisely bonded to the load cell's internal structure. When a force is applied (e.g., as a bolt is tightened, compressing the load cell), the body of the load cell deforms slightly. This deformation is detected by the strain gauges, causing a change in their electrical resistance. This resistance change is then converted into a measurable electrical current that is proportional to the force applied.

Applications

Donut load cells are widely used in applications where direct inline force measurement is required, especially in situations with limited space. Common applications include:

• Bolt force measurement: Measuring the clamping force applied by a tightened bolt in structural assemblies, machinery, or automotive applications.

• Press fitting operations: Monitoring the force applied during assembly processes where components are pressed together.

• Structural testing: Measuring loads on support posts, legs, or other structural elements.

• Overload protection: Acting as a safety device to monitor excessive forces in machinery.

Their robust construction, often from stainless steel, makes them suitable for harsh industrial environments, providing accurate and reliable force measurements crucial for quality control and operational safety.