The pharmaceutical and semiconductor industries are adopting a new “slimmer” pipe insulation that can reduce cleanroom size requirements and eliminate downtime costs, argues T-Tubes.
In some respects, the insulation traditionally used in cleanroom manufacturing is like those 1980s-era cellular phones: clunky and somewhat prone to performance problems. But then, of course, the conventional open-celled polyethylene foam insulation used in cleanrooms dates back to the 1980s or earlier.
The problems with those cumbersome insulation designs become pronounced in the manufacturing cleanroom environment, where thousands of feet of fairly narrow reactor piping form a congested maze of plumbing, once the insulation has been installed. A half-inch (½”; 12.70mm) line with 3” (7.62cm) insulation becomes a hefty 6.5” (16.5cm) in diameter. When you consider the multitude of lines in the typical manufacturing cleanroom, it is no wonder the space gets crowded.
“One of the problems with the traditional melamine fibre or foam insulation design used in most cleanrooms is that it severely constricts the space needed by technicians to access the many points in the lines where instruments and controls are located,” says Mark Ginchereau, vice-president of Termar, a maintenance contractor and insulation installer based in Ventura, California.
The traditional melamine fibre or foam insulation design used in most cleanrooms severely constricts the space needed by technicians to access the many points in the lines where instruments and controls are located
Ginchereau adds that, until recently, the only alternative to having a cleanroom densely packed with open-celled or polyethylene insulated lines was to build a larger cleanroom and install longer lines so that there would be more “elbow room” for technicians – a highly expensive solution.
But bulk is not the only drawback to conventional insulation, he points out. Standard open-celled insulation sheds particulate when cut. This makes it necessary to provide additional protection from cross-contamination and exposure. Yet standard open-celled insulation can also shed particulate due to everyday contact from workers who need to gain access through tight spaces. Any uncontrolled particulate shedding can require extensive replacement and unscheduled cleanroom downtime.
Ginchereau also mentions that cleanrooms with melamine fibre-filled insulation in some chilled-water applications may be susceptible to condensates forming in fibre, due to chinks or even cracks resulting from impact damage or normal wear and tear from worker contact. Condensate formation can provide a breeding ground for biological growth, a highly undesirable intruder to any cleanroom environment. The condensate problem aside, cracks or other leaks in insulation are detrimental to maintaining exacting temperatures in cleanrooms.
Another serious concern about the use of bulky traditional insulation is the possibility of serious worker injuries due to contact with superheated or frigid lines. Ginchereau says that the greater the congestion of plumbing due to the use of insulation, the greater the potential for injury.
Another serious concern about the use of bulky traditional insulation is the possibility of serious worker injuries due to contact with superheated or frigid lines
One of the newer materials that has provided a breakthrough in cleanroom insulation is Kynar PVDF-based, high-purity Zotek F foam. This speciality plastic material is a closed-cell foam that in a thickness of only ¼” (6.35mm) offers chemical and heat resistance as well as other properties that are equivalent to eight times that which conventional foam provides for cleanroom applications. In other words, ¼” of Kynar PVDF insulation is equivalent to 2” (5.8cm) of open-celled insulation.
In recent years, UFP Technologies, a Georgetown, MA-based producer of innovative foam, plastic and composite products, incorporated the new PVDF technology into an advanced tube and pipe insulation system specifically developed for process lines and equipment in cleanroom environments.
“This product rewrote the book for cleanroom insulation,” says Ginchereau, who recently installed it at a large bio-pharmaceutical laboratory in California.
Known by the brand name T-Tubes, this advanced insulation replaces the bulky traditional product with a wall thickness of only ¼” (6.35mm).
“When you consider that instead of 6”-plus insulation on dozens of reactor lines, you are adding only ½” in diameter to a 1” or 2” pipe, you can save a lot of real estate,” Ginchereau says. “Overall, the insulation is taking up only about a tenth of the space of traditional fibreglass.”
This space saving translates into many benefits, including reduced cleanroom size requirements. When you consider the space requirements of cleanrooms housing multiple reactors connected to thousands of feet of pipeline with “fat” insulation, the amount of space is dramatically reduced with the use of T-Tubes.
Another serious concern about the use of bulky traditional insulation is the possibility of serious worker injuries due to contact with superheated or frigid lines
Also, Another serious concern about the use of bulky traditional insulation is the possibility of serious worker injuries due to contact with superheated or frigid lines as well as less exposure to contact with super-heated or super-cooled lines.
The product offers several other features that render important benefits to operators of manufacturing cleanrooms. The T-Tubes system includes custom-moulded coverings for fittings, and an overlapping, self-adhering tape that provides a superior seal. This reduces the possibility of condensate, which can saturate ordinary foam insulation, creating leaks and enabling biological contamination.
“In a few instances during this project, we were able to collaborate with the T-Tubes engineers, to custom design components on-the- fly,” he says. “Within a couple of days, I received a sample that we could test and, in most cases, it was a good solution. It worked perfectly.”
Unlike traditional open-cell insulation, this technology does not shed when cut, meaning fewer impurity problems
Unlike traditional open-cell insulation, this technology does not shed when cut. This means fewer impurity problems while cleanrooms are live, and no need for protective bags and hoods or downtime during installation.
The PVDF-based product does not burn or smoke either, which is very important to pharmaceutical cleanrooms where valuable drugs could become tainted and lost if exposed to smoke. In fact, this is arguably the only pipe insulation that is compliant with the Factory Mutual (FM) Approvals 4910 standard for cleanroom materials. It has also successfully completed FM’s 4924 Pipe Chase Flammability Test and is rated for use by the semicon industry.
Ginchereau describes this single-layer insulation system as very easy to install, which spells major savings of manpower. Traditional foam or PU products coated with melamine require added installation time and effort because there are two layers involved. In one case, the labour savings on a 30,000ft insulation project saved more than $800,000.
