Automotive engineers design car and truck suspensions for stability, riding comfort, and reliability. One important area of focus is the coil-over-shock, or MacPherson strut, contained in many automobiles. To minimize the damper friction in the strut or shock, design engineers use coil springs that exhibit a force line (or force vector) that minimizes the side loads and moments on the damper or shock. Reduced damper friction makes for better riding comfort, better steering stability, and less wear on the seals. To design and manufacture these springs to design requirments, we must be able to reliably and accurately measure the force line of the spring.
For this force line testing, we supplied the SF1491 Force Line Testing System with Partner™ Spring Testing Software for testing springs. The SF1491, with an axial force capacity of 50 kN, compressed the springs and precisely measured the load centers (piercing points) on the top and bottom of the spring. We also determined the axial spring rate and several load-at-height values. Our customer used the results of the test to qualify their designs and production pocesses, to set up of their spring production runs, and for final quality control testing.