FREQUENTLY ASKED QUESTIONS
How many cycles can an iCPV design handle?
iCPV’s can be designed to handle a broad range of cyclical requirements. To date, the highest number of cycles an iCPV has been subjected to is 18,000 hydrostatic cycles (13,000 from 50 psi to 4,500 psi and 5,000 cycles from 50 psi to 5,625 psi). After the completion of this simulated 20 year life cycle the vessel showed no reduction in burst pressure. This was performed on a 325 L tank.
What types of fibers have you used?
IC has experience with a range of different fibers and manufacturers. The primary material used is carbon fiber, but basalt, glass and aramid are among others used.
What burst pressures have iCPV designs achieved?
The maximum burst pressure achieved to date was 14,400 PSI on a 325L vessel, after a 18,000 cycles.
What is PV/W and where does the iCPV rank?
PV/W is the shorthand equation for pressure vessel efficiency, where the burst pressure (pounds per square inch (PSI)) of a tank is multiplied by its internal volume (cubic inches) and divided by the weight (pounds) or (pressure x volume / weight). The higher the number, the better the efficiency. Out of 140+ space COPVs and pressure vessels, IC ranks #1, with 26% higher efficiency than any other vessel used to date.
How light are IC tanks compared to other pressure vessels?
When compared to traditional metallic tanks, the iCPV can weigh up to 90% less. Compared to composite overwrapped pressure vessels (COPVs), iCPV can save 20-40% weight, while increasing storage capacity by eliminating the need for the liner.
What is a COPV vs an iCPV?
COPV refers to a composite overwrapped pressure vessel. This means the composite material (whether carbon, glass, aramid fiber, or other) is wrapped over and around a liner, typically made of metal (such as titanium or spin formed aluminum) or plastic (such as high-density polyethylene (HDPE)). In COPVs, the liner is the mandrel, which serves as the shape of the tank. In addition, the liner serves as the permeation barrier or gas barrier.
The infinite composite pressure vessel, or iCPV, uses a removable mandrel process. The mandrel still provides the shape of vessel, however it’s does not remain a part of the vessel, leaving only the composite material and resin to serve as the strength and permeation barrier.
Are there permeation issues by not using an internal liner?
The infinite Composite Pressure Vessel design has achieved a helium leak rate of 2.5 x 10-6 SCCS at 310 Bar.
What are the different tank sizes you make?
IC has made a collection of tanks ranging from 2.5” [65mm] diameter to 25.6” [650 mm] diameter, covering internal volumes of 0.1L to 325L. The current equipment is restricted to 30” [762 mm] outer diameter to 120“ [3,048 mm] in overall length.
What type of fuels are compatible with the iCPV?
The iCPV has been used to store methane (compressed natural gas (CNG)) as well as inert gases such as helium, argon and krypton. IC has also validated all-composite tanks for use with oxidizers (LOX & N2O) and hazardous materials such as high test peroxide (HTP).
What is the MEOP for the iCPV?
The highest maximum expected operating pressure (MEOP) for an iCPV to date has been 6,000 PSI. This is not a limitation, but merely the highest use case so far. Highest Burst has been 14,400 psi after 18,000 cycles.
Do you make non-cylindrical tanks?
Yes. We've successfully created a medium pressure (3,000+ psi burst) tank that is non-cylindrical. We've also created designs for large water and waste vacuum tanks. Let us know about your non-cylindrical tank needs.
