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 hydrocycles (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.
What types of fibers have you used?
ICT 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, ICT ranks #1, with 26% higher efficiency than any other vessel used to date.
How light are ICT 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 (weather 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?
Linerless pressure vessels experience similar permeation rates at plastic-lined tanks. In short, there is some leakage, but the leak rate has been acceptable by many vehicular applications from compressed natural gas storage to nitrogen pressurant tanks for launch vehicles. We're also striving to reduce permeation rates with the use of additives within resin systems.
What are the different tank sizes you make?
ICT has made a collection of tanks ranging from 5” [127 mm] internal diameter to 21.5” [546 mm] internal diameter, covering internal volumes of 3L 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. In addition, as of 2018, new research is being done on high-test peroxide (HTP) and breathable oxygen compatibility.
What is the MEOP for the iCPV?
The highest maximum expected operating pressure (MEOP) for an iCPV to date has been 5,500 PSI. This is not a limitation, but merely the highest use case so far.
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.