Ring load cells and through-hole force transducers

Precision in ring form. Our ring load cells and through-hole force transducers measure forces directly where a screw, shaft, threaded rod or bolt passes through the sensor. They are also known as annular load cells or force measuring rings, and in their flat version under a screw head as force washers. Thanks to their flat design and central through hole, they can be integrated seamlessly into existing constructions.

Ring load cells and annular force transducers from 50 N to 2,500 kN

Ring load cells are excellently suited for the reliable measurement of medium to very high compressive forces. The most common areas of application are press spindles, cutting tools, propeller shafts, test benches and screw force measurements. The compact ring load cells LRBA to LRBI cover measuring ranges from 50 N to 1,000 kN. They are made of stainless steel, available up to protection class IP68 and optionally as a high-temperature version up to +250 °C.

Our ring load cells are also available in a miniature design for applications with very limited installation space or for detecting very small forces.

Force washers for bolt preload

A force washer, also called a load washer, sits under the screw head or nut like an ordinary washer and measures the clamping force of the screw connection directly. The LREA force washer covers 10 kN to 300 kN for screw sizes M6 to M48. It is optionally available in an ATEX/IECEx version or with SIL 2 for safety-critical applications.

Through-hole load cells for shafts, tie rods and test machines

With a through-hole load cell, the force is applied through the central bore, for example via a tie rod, a press spindle or the piston of a materials testing machine. The LRAA covers 10 kN to 1,000 kN with 2 mV/V. The LRAB outputs 4–20 mA, ±5 V or ±10 V directly. For very high loads up to 2,500 kN, for example on anchors and in structural monitoring, we offer the LRLA anchor load cell. The inner diameter of the LRBC can be adapted to your design.

Which design fits your application?

• Force washer under a screw head or nut: LREA
• Through hole for shafts, tie rods or test machines: LRAA, LRAB, LRLA
• Compact ring load cell for presses, test benches and machine monitoring: LRBA, LRBB, LRBE, LRBF, LRBI, LRBC

Features of Ring Load Cells

• Central force application: The ring geometry allows machine elements to be passed through – ideal for monitoring pre-tensioning forces on screw connections or bolts.

• Extremely flat profile: Thanks to their minimal height, these sensors are perfect for applications with limited space, such as in presses or assembly fixtures.

• Robust design: Made from high-strength stainless steel and usually hermetically sealed, they can withstand harsh industrial environments and high load cycles.

• High rigidity: The solid construction ensures very low deformation under load, which enables highly precise measurement results and a high natural frequency.

On request, calibration is carried out by a laboratory accredited to ISO/IEC 17025.

Further designs can be found under Buy force transducers, ring load cells for tanks and scales under Buy load cells.