Why is there a grey area on the left side of every Firestone load curve in the design guide stating: “Do not use Airstroke in the shaded area without consulting Firestone”.
Firestone replies that it is committed to selling products to our customers that will operate safely and provide the best possible performance and life in their applications.
There are really two types of failures that can be classed as “over extension”. Most users can fully understand the results of extending a part to its full limit without restriction. Under the best case the plate will bend and the part will start to leak. Under the worst case there is an explosive decompression of the significant air volume contained in the air springs and the potential for damage to equipment, or even harm to people working in the area.
This is why Firestone puts this shaded area in our graphs, and they have for over 40 years.