Load Washers 101

Load washer load cells are a versatile product used throughout a wide range of industries and applications. These force measurement donut-styled components are frequently used to measure and monitor clamping forces, fastening control, bolt loading and other compressive loads.

A load washer looks remarkably similar to the washers used to distribute the load of a threaded fastener like a screw. A load washer also works in a similar fashion, however they’re made of rugged stainless steel material and use proprietary measurement technologies, like strain gages, which allow it to measure press and compression force rather than just distributing the load.

Interface offers eight different models of load washers of varying sizes and force measuring ranges, all the way from 11.2 to 1124K lbf. The Interface Load Cell Load Washers can be easily designed into products to continuously measure and monitor compression forces. The variety of load washer styles and capacities, all using the thru-hole feature, give product engineers and designers multiple choices for what best fits their application and use case. Specifications for each model are available, along with design files and model ranges online.

For instance, our LWPF1 Load Washer Load Cell is designed to measure press force and is rated at capacities from 450 to 22.5K lbf. It offers a large thru-hole and short height for tight spaces.

Another popular Interface load washer is the LWCF Load Washer Load Cell which can be used to measure clamping forces and also bolt tightening. It has a capacity range of 3.4K to 337.2K lbf and is ideal for determining bolt preloads. We offer precision, high-capacity, and environmentally safe load cell load washers.

Interface also offers two models that have pre-manufactured mounting holes for installation, which are ideal for press force control and measurement. You can see our entire line of load washer load cells here.

Interface load washers are smaller in size, allowing for standard and customized sensors of this type to be used by original equipment manufacturers. We commonly get requests for these load cells for use in industrial automation equipment, medical device testing, test and measurement projects as well as products that need a small but precise sensor.

We’ve also included real-world applications of load washer load cells below. This will give you an idea of the types of projects in which this force device can be used to determine accurate force data used to refine or confirm the design of product or tool.

AIRCRAFT SCREWDRIVER FASTENING CONTROL

An airplane manufacturer was able to calibrate their screwdriver by measuring its torque, rotational speed, and angle, when attaching materials together for their airplane. They were also able to measure the forces being applied to the screw, to ensure it was not applying too much torque to the components. With a T15 Hex Drive Rotary Torque Transducer attached to the fastening work bench, the system measured and recorded torque, rotational speed, and angle of the screwdriver. The LWCF Clamping Force Load Washer  is installed, measuring the forces applied on the screw being fastened. Results are sent to the SI-USB4 4-channel USB Interface Module, which is connected to a laptop where data is logged, graphed, and displayed for test results.  This configuration provided data to calibrate their screwdriver by measuring its torque, rotational speed, and angle, when attaching materials together for their airplane. They were also able to measure the forces being applied to the screw, to ensure it was not applying too much torque to the components.

BOLT FASTENING FORCE AND TORQUE

Using a General Purpose Load Washer Load Cell Model LW in conjunction with a Model T12 Square Drive Rotary Torque Transducer, the customer was able to align force and torque measurements to desired levels. This was accomplished by combining the sensors with the high sample rate of the data logging and graphing capabilities of the SI-USB, capturing real-time force and torque levels for examination. The fasteners were tightened to the specified force and torque requirements and were safely installed without impairment to themselves or the joint material. The customer was able to measure the rapid event effectively and accurately.

To learn more about load washer load cells and our entire product lineup or to talk to an engineer about the specific needs of your next project, please call us at 480-948-5555.