When it comes to various compression and coil springs, one of the primary purposes of these items is to resist force using compression. Weight is applied to coils, which compress at a given spring rate, and the force at play here is often a defining factor in the precise spring type you choose.
At J and J Spring Enterprises, we stock a variety of coil springs among our wide array of custom springs, which also include extension springs, flat springs and many others. When coiled springs are compressed to a certain point, they reach a state known as solid height – this two-part blog will go over everything you need to know about solid height and why it matters within spring manufacturing, from its basics and calculation methods to some of the solid height alignments certain clients or manufacturers might be looking for.
Solid Height Definition and Alignment
As we noted above, compression springs will compress to a certain point when weight is placed on them. At a certain point, however, each coil will be touching another and the spring can no longer deflect any further downward – this is the point at which this spring has reached its solid height.
Now, it’s important to note that solid height does not necessarily mean the spring cannot withstand any further force. In fact, the majority of compression springs can withstand significant additional force, but do so without the coils compressing any further past solid height. Compression springs will contain dead coils on each end, intentionally wound to touch the nearest coil so the overall spring stands straight up and doesn’t fall over.
How It’s Calculated
Calculating solid height for a given spring is relatively simple, but perhaps a touch more complex than you had imagined. While some assume you simply count the number of coils present and multiply this number by the width of the coil being used, you actually have to add one to the total coil number to account for 11 actual “sides” of wire. So for a 10-coil spring using 0.29-inch wire, the format for calculating solid height would be multiplying 0.29 by 11, rather than 10, for a solid height of 3.19 inches.
There is one exception here: When calculating solid height for springs with closed, ground ends, you do not need to add one to the coil number, instead using the actual number for multiplication.
Precision Within Solid Height
One of the top reasons solid height is important is for spring manufacturer use. Think of a compression spring used in a bottle-filling machine, for instance, one meant to automatically move bottles from station to station – facility operators will want this device to have the spring reach solid height at the precise moment when the proper amount of liquid is poured in, signaling the machine to shut off and move to the next station.
In part two, we’ll go over other uses for solid height and why it’s important within spring manufacturing. To learn more about this or any of our custom spring manufacturing or wire forming services, speak to the staff at J and J Spring Enterprises today.