Steel 80 vs 100 vs 117 vs 133

[ScubaFanFL]

Steel tanks 80, 100, 117 and 133 all have the same max fill pressure of 3442. What's the benefits of having 133 over 80. The price of 133 cu ft is almost $200 more than 80.

 

[yardpro]

more air

 

[Locus]

Although they share a working pressure of 3442psi, the tanks you have listed differ in many important respects, such as height, girth, weight, price, and buoyancy characteristics.

The numbers you are using indicate the quantity of air that they hold when full in cubic feet, so the 133 holds over 150% as much air as the 80 when they are both filled to 3442 psi, and this is why it is more expensive. Consequently, it is also a much larger and heavier tank than the 80. Larger tank + same pressure = more air.

Here is a chart that lists the specs of many commonly available tanks. It also identifies tanks by manufacturer, because not every producer of tanks builds them to the same exact specifications. For example, although they are nearly the same dimensions, a 100 made by PST is 1.3 lbs negatively buoyant when empty, where a 100 made by Faber is 7.6 lbs negative when empty.