Worthington optimizes fuel storage in large diameter Type III cylinder

51 Worthingtonii 400A 26.2-in. diameter cylinder has joined the company’s line of compressed natural gas tanks for heavy-duty trucks. First shown at the 2015 Alternative Clean Transportation Expo in Dallas, it is Worthington Industries’ largest Type III CNG cylinder and, product engineers contend, provides superior fast-fill efficiency. An inner aluminum liner dissipates heat during fast filling, affording an additional 15 to 25 percent more fuel storage compared to Type IV cylinders of similar size.

The large diameter cylinders fill to rated capacity to enable longer routes or refueling intervals. As with all Worthington Type III cylinders, the aluminum inner liner provides an added safety feature by reducing the risk of flex or fracture in the outer composite reinforcement should impact occur.

51 Worthingtoni 400

The 26.2-in. diameter cylinder affords fuel storage volume well suited to mixers in fast fill or time fill conditions, making optimal use of frame rail space.

“We believe the fast-fill efficiency and durability of our new large diameter cylinder will be a welcome addition to the market, maximizing the fuel system design for original equipment manufacturers,” says Worthingon Alternative Fuels General Manager Wayne Powers. “Our 30 years of experience producing cylinders which safely and efficiently store and transport alternative fuels has made us a trusted name in CNG cylinders. Of the hundreds of thousands of cylinders produced for alternative-fuel applications globally, we have never had a composite cylinder failure.”

Worthington Type III vessels, including the new large diameter model, are built to aircraft, railcar and watercraft CNG cylinder standards, he adds, which are more stringent than typical over-the-road standards. The manufacturer’s testing requires a minimum burst safety factor of 3.0 times the rated pressure, along with sidewall structure impact testing. The U.S. National Highway Traffic Safety Administration Federal Motor Vehicle Safety Standard (FMVSS) 304 standard requires a minimum CNG cylinder burst safety factor of 2.25 times the rated pressure, and does not stipulate sidewall structure impact testing.

The new large diameter cylinder is also certified according to the American National Standards Institute/Canadian Standards Association NGV2 standard. It features gas-tight construction thanks to its inner aluminum liner, which prevents permeation. There are also no filling restrictions in hot or cold weather. The aluminum liner likewise provides heat tolerance in the event of a fire, and transfers heat to the pressure relief device. — Worthington Industries, Columbus, Ohio; www.worthingtonindustries.com