Foam insulation

Switching the blowing agents used to produce foam insulation on panels and, in some cases, reconfiguring their production processes, is nothing new to trailer and truck body manufacturers. “We've had to make changes before with blowing agents,” says Rick Mullininx, vice president of engineering for Great Dane.

“When I first started with the company 25 years ago, we were using R-11,” he says. “It had a high ozone-depleting factor, so we switched to R-141b. And then that was banned and so we switched to R-22. Now that's been banned.”

Most truck body and trailer manufacturers say the new regulation governing the use of ozone-depleting blowing agents will not radically alter their manufacturing processes or compromise product quality. However, they say it will dramatically increase production costs because the new blowing agents cost significantly more per pound.

“In terms of passing that on to the customer, I don't know if the marketplace will accept an increase right now,” says Tracey Maynor, senior vice president of sales and operations for VT Specialized Vehicles Corporation (VTSVC), parent company of Hackney and Kidron.

“The good thing is that some of the material costs have begun to stabilize, so the effects of a foam increase will be less visible to the marketplace,” he says. “But with the reduced volumes that the marketplace is experiencing today, a manufacturer's ability to pass on a price increase is going to be very difficult.”

Phaseout targets

All of this is in reaction to the Montreal Protocol on Substances that Deplete the Ozone Layer, an international treaty signed in 1987. It was designed to protect the ozone layer by phasing out the production of substances with ozone depletion potential (ODP).

In the US, Class I substances were subject to the first round of phaseout targets. Class I substances have an ODP of 0.2 or higher and include halons, chlorofluorocarbons (CFCs), methyl chloroform, carbon tetrachloride, and methyl bromide.

Section 604 of the US Environmental Protection Agency's Clean Air Act set the phaseout targets for Class I substances, including a ban on production and import of halons that took effect on January 1, 1994, and a ban on production and import of other Class I ODP substances — excluding methyl bromide — that took effect on January 1, 1996.

Class II controlled substances have an ODP of less than 0.2 and were subject to a later phaseout schedule than Class I substances. Class II substances are all hydrochlorofluorocarbons (HCFCs). These were developed as transitional substitutes for Class I substances and have many of the same uses as CFCs.

Of the 34 HCFCs, the most widely used have been HCFC-22 (a commercial refrigerant), HCFC-141b (a solvent and foam-blowing agent), and HCFC-142b (a foam-blowing agent and component in refrigerant blends).

The phaseout framework was established by the EPA on January 21, 2003 in its final rule 68 FR 2819 that banned production and import of virgin HCFC-141b. Production and import of virgin HCFC-22 and HCFC-142b were to be banned on January 1, 2010.

But at the September 19, 2007 Meeting of the Parties in Montreal (for Montreal Protocol signatories), the Parties agreed to a more aggressive phasedown of HCFCs, adopting a March 1 2008 deadline.

Foam-blowing substitutes

Mullininx says Great Dane has chosen to go with HFC-245fa instead of R-22 as a blowing agent. All the parameters are the same with HFC-245fa, he notes, but the peel strength is a bit higher for better delamination resistance.

Maynor says VTSVC will switch to HFC-134a and doesn't expect any changes in the manufacturing processes for its refrigerated bodies and Emperor food service trailers. Nor does the company anticipate any quality difference between HFC-134a and R-22. “If anything, he says, “the 134, based on our tests, will provide less opportunity for foam shrinkage.”

For its refrigerated trailers, Hyundai will be changing from HCFC-141b to an undetermined blowing agent — either HFC-245, cyclopentane, or water, says the company's vice president of research and development Howard Yurgevich.

“Water is very good because you don't have any problem with ozone depletion, and obviously it's easily available and probably has the lowest cost addition,” he says. “But it does require a higher density to maintain the stability of the trailer and foaming, and it's not as efficient an insulator.”

Yurgevich says HFC-245 has better insulating factors and no ozone-depletion potential but is very costly to purchase and use. Cyclopentane is not as expensive as HFC-245 and has reasonable insulating properties. However, it is considered a flammable liquid, condenses at room temperature, and requires higher densities to maintain dimensions.

Further modifications

More changes for foam-blowing agents will occur on January 1, 2015. On that date, as part of the phaseout of all HCFCs, sale and use of HCFC-22 and HCFC-142b will be banned, except for transformation or servicing refrigeration and air-conditioning applications. The EPA will not permit newly manufactured HCFC-22, HCFC-142b, or blends containing either substance, to be used for charging new equipment.

Then starting January 1, 2020, production and import of HCFC-22 and HCFC-142b will be banned entirely in the US. Once this happens, only recycled/reclaimed or stockpiled quantities of HCFC-22 and HCFC-142b will be available for servicing existing equipment.

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