Dr. Roy J. Plunkett’s Fortunate Accident

Sometimes we make a mistake, but we learn from it.  And sometimes, if we’re lucky, we make a mistake and the end result is better than we intended.  That happens to be the case with Roy J. Plunkett and his accidental discovery of polytetrafluoroethylene, commonly known as Teflon.  But first things first, let’s meet the man behind the accident.

Before he was a doctor, Roy Plunkett grew up during the Depression on farm in New Carslisle, Ohio.  Some years later, Plunkett received his bachelor’s degree in chemistry from Manchester College in 1932.  Following his studies at Manchester College, he moved on to the Ohio State University where he received his master’s degree in 1933 and his Ph.D. in 1936.  Upon completing his academic career, Plunkett was hired by DuPont, the setting for this fortunate accident.

One of Dr. Roy Plunkett’s first assignments at DuPont’s Jackson Laboratory in Deepwater, New Jersey, was to study new chlorofluorocarbon refrigerants.  Basically, he was looking for a new alternative to the potentially dangerous refrigerants of the time, sulfur dioxide and ammonia.  However, on April 6, 1938, Plunkett and his assistant, Jack Rebok, checked on a 100-pound container of tetrafluoroethylene (TFE) gas, and found one of the cylinders had not discharged when they opened the valve.  Although the cylinder seemed empty, they found it had the same mass when they weighed it.

Plunkett and Rebok opened the cylinder and found that the gas had solidified into a white powder.  Naturally, Plunkett was inclined to test the properties of the solid.  He found it that it was slippery, chemically inert, and had a very high melting point. Scientifically speaking, TFE had polymerized into polytetrafluoroethylene (PTFE).  Now, for the non-scientists in the room, Plunkett discovered what would later be patented by DuPont as Teflon.

Plunkett, who himself called the discovery an accident, had found a product that would change a wide range of industries.  PTFE properties were originally used as a lubricant, but they have since branched out into cookware, electrical wiring, aerospace technology, etc.  In fact many heat exchangers found in space heating, air conditioning, and refrigeration utilize this technology.  So, at the end of the day, I would say Dr. Roy J. Plunkett learned from his accident, and in one way or another, we have all benefited from it.



Better Understand Heat Exchangers

Heat exchangers aid in transferring heat from one fluid to another.  Depending on the individual structure of a heat exchanger, a wall may separate the fluids in order to prevent them from combining.  Other designs may allow the fluids to comingle without affecting the integrity of the heat exchanger and its desired result.  In most celebrated heat exchangers, the surface area of the wall between the fluids is maximized while simultaneously minimizing the flow’s resistance.

Heat exchangers are common staples in many industries and used for implementation in many products including air conditioners, refrigerators, and space heaters.  In addition, heat exchangers are applied in chemical processing settings and those of power production.  Heat exchangers are also used prominently in the automotive industry for car radiators.

Heat exchangers involve three arrangements of airflow: counter flow, parallel flow, and cross flow.  Counter flow involves fluids entering from opposite sides; parallel flow involves fluids coming in from the same end and moving parallel to one another; and, cross flow involves moving the fluids in a perpendicular fashion.

To date, there are four separate designs in manufacturing heat exchangers: shell and tube, plate, regenerative, and intermediate.  The shell and tube heat exchanger is most typically manufactured and used across many industries.  This particular heat exchanger has multiple, finned tubes.  One of the fluids runs through the tubes while the other fluid runs over them, manipulating the temperature.

Please contact us regarding your specific job or heat exchanger desired.  Please refer to the quote requests off of our PTFE tubing and heat exchanger site.

PTFE: The Future of Tubing

Polytetrafluorethylene or PTFE is one of the world’s most versatile thermoplastics. PTFE is replacing carbon and other types of metal tubing, quickly naming PTFE the future of tubing.  PTFE tubing can withstand extreme temperatures and has phenomenal UV resistance as well as strong weatherability.  This high quality tubing has a slippery and smooth surface, and makes a superb insulator.

In high pressure- low velocity load conditions, properties in PTFE make it appropriate to be used as bearing pads. PTFE properties are also useful applications for heat and non-heat shrink tubing, heat exchangers, and coatings.

With such a wide variety of uses, and its strong withstanding for wear and tear, PTFE will continue replacing other tubing material and serve our industries for a very long time.

In Need of a Shell and Tube Heat Exchanger?

A shell and tube heat exchanger is just what it sounds like.  Well, provided you’re familiar with heat exchangers, it should be just what it sounds like.  If you’re not, a heat exchanger is basically a device used for efficient transfer of heat.  Common uses are found in space heating, refrigeration, air conditioning, and other large scale operations like power plants, petroleum refineries, and sewage treatment.  But, let’s get back to shell and tube heat exchangers.

A shell and tube heat exchanger, obviously, is a type of heat exchanger.  It’s also, and perhaps not so obviously, the most common type of heat exchanger found in oil refineries and other large chemical processes.  So, how do they work?  Basically, they consist of a larger outer tube (the shell) with a bundle of smaller tubes (the tube) inside of it.  The set of tubes found inside the shell—called a tube bundle—can be composed of several types of tubes: plain, longitudinally finned, etc.  Since you have an outer shell as well as a tube bundle, multiple liquids or gasses can pass through at once for heating.  Essentially as they flow through together, one will emit heat through the tubing, heating the liquid or gas.

The key benefits of our shell and tube heat exchangers include:

• Ultimate in ultra-purity and chemical inertness
• Unidirectional shell and tube side flows allow for complete purging
• Stagnant pockets are eliminated during continuous or batch operation.
• Unit can be operated in true counterflow or in parallel flow mode.

So, if you feel you may be in need of a shell and tube heat exchanger, let us help you out.  With expertise, we’ll be sure to help you select the right sizes and materials for any of your shell and tube heat exchanger needs.

Choosing an Immersion Heat Exchanger

Details of a heat exchanger’s type, size, and composition must be considered from the beginning.   Immersion heat exchangers offer serpentine coils, u coils, pipe coils, grid or plate coils.  Immersion heat exchangers are a popular choice due to economic pricing and the ability to fit large and small systems.

Once you choose the type of heat exchanger you need, the materials of composition must be considered.  Heat exchanger production is contingent on finding a good mixture of economy and performance.  Fluoropolymers such as PTFE can be used to produce high-quality heat exchangers.  Buyers want to purchase exchangers made of material that can withstand highly-corrosive atmospheres.

Please access our comparison of materials chart in order to make the best selection for your needs.

There are a number of factors to consider regarding how well the heat exchanger will work.  For one, the effectiveness of the exchanger will be contingent on how quickly liquid gets heated.  Secondly, how well the heated pool can be maintained is also a point of concern.  In addition, any work being performed in the pool of liquid will distract from the heat of the pool.  Lastly, the overall size in square feet of the heat exchanger plays a determinant on performance.

Find More Information About Fluoropolymers

We operate within a very niche business, despite the fact that PTFE tubing, PVDF tubing, heat shrink tubing, and our other customized products can be used by an array of additional industries.  We maintain literature on our Web site regarding PFA properties, PTFE properties, and our other, offered fluoropolymers, but you may desire to learn additional information, so this post will host links to other Web sites featuring information about PTFE as well as other fluoropolymers – we hope the additional information helps you learn of the benefits and opportunities present with fluoropolymers.

The Fluoropolymers Division (FPD) of The Society of the Plastics Industry, Inc

This site is a good resource point for those seeking additional information about fluoropolymers.  The site instructs about the benefits of PTFE tubing, PFA tubing, and others, as well as provides PDFs featuring suppliers of products and services.

Fluoropolymer Wikipedia

Wikipedia is a good place to do some preliminary research regarding just about any topic you can imagine.  Wikipedia offers a general post on fluoropolymers along with links leading to information regarding PVDF tubing, PTFE tubing, PFA tubing, and other fluoropolymer products.

Fluoropolymer Facts

The Fluoropolymer facts site provides just that – the facts on fluoropolymers.  The site educates the layperson on the safety benefits as well as all of the opportunities present when working with PTFE tubing, PVDF tubing, and beyond.  The site provides the history of fluoropolymers as well as an interesting ‘myth busting’ section.

The Benefits of Custom Plastics

There are certainly many places to procure plastic supplies. Basic plastic tubing and PVC pipes are available at any hardware store. And lab and medical suppliers can get you heat-resistant and chemical-tested tubes. But you know as well as we do that if you are working within a framework that requires 90-degree tubes, U or Z-shaped tubes, or ultrapure sanitary flow, Home Depot just won’t cut it.

At Fluorotherm, we specialize in custom plastic molds that are sure to meet your specifications because you design the blueprint. You give us your specifications, the needs of your project and the size you are working with and we give you the tubing that will get the job done.

Our custom fabricating division uses your print to create a mold, creates test products and ensures the product holds up to your specifications. Upon delivery, we show our work with certificates of performance and inspection reports, giving you the accountability you need and saving you time. We get it right the first time so you can get to work developing your technology project.

Our heat exchangers, heat-shrink tubing, PFA tubing and sanitary, wear-resistant chemical transfer tubes are trusted in labs across the world. As such, we work with many technology developers working on proprietary projects. We have protections in place to ensure that the details of your project are never divulged. We can create a confidentiality agreement for both your production blueprints and any other details you provide.

The reason plastic is one of the worlds most popular materials is its pliability. Plastic can be made into anything you want. Yet, so few suppliers take the time to build to your specifications. So when Home Depot and Lowes let you down, you can still get exactly what you need at Fluorotherm.

FEP Basics and Applications

FEP is a valuable insulator used in many applications. It was invented by DuPont and stands for Florinated Ethylene-Propylene. FEP is a copolymer of hexafluoropropylene and tetrafluoroethylene.

FEP heat shrink tubing is similar to PTFE tubing because of its electrical and friction properties and its chemical resistance. It differs in that it is melt-processible. FEP properties offer benefits of being inert to most chemicals and solvents, unaffected by weather elements, less expensive than alternative TFE, flame retardant, and approved with FDA and USP Class VI.

The many applications for FEP include:

•    Heat Shrink Tubing & Non-Shrink Tubing
•    Heat Exchangers
•    Medical Tubing
•    Telephone Primary wire-Coating Insulation
•    Conventional Wire-Coating insulation
•    Jacketing for Telephone and Conventional Primary Wires
•    Release Film
•    Valve & Chemical Equipment Lining
•    Cable (CAT V)
•    Foamed Coaxial Cable
•    Foamed Plenum Wires
•    Computer Interconnects
•    Fiber-optic Applications
•    Underground Sampling Water Lines
•    Coatings
–    Textile Dry Cans
–    Chemical Processing Equipment
–    Heat Sealing Equipment
–    Mold Release

More About Heat Shrink Tubing

We are proud to supply our customers with Heat Shrink Tubing along with our other fluoropolymer products.  Those that are not very familiar with heat shrink tubing may have some general questions.  The following post seeks to address some elementary shrink tubing questions.

What is heat shrink tubing made from?

Heat shrink tubing can be made from a variety of thermoplastics.  Fluorotherm utilizes its PTFE and other plastic products to produce our own version of the tubing.

How do you make the plastic shrink?

Heat shrink tubing is not like common plastics.  Cross-linking enables the tubing to take on different properties and abilities.  Polymers are exposed to radiation, which alters their molecular structure.  The covalent bonds that are formed help provide the plastics with a ‘memory’.  Once the heat shrink tubing is stretched to serve as a housing, the tubing can then be heated to return to its original size, securely covering another entity in the process.  This is why heat shrink tubing is used in a large variety of electrical jobs.

Do all kinds of tubing shrink in the same manner and size?

Heat shrink tubing has an associated shrink ratio.  The ratio is a measurement alerting how small the tubing becomes when shrunken in comparison to its potentially expanded size.  For example, a 3:1 ratio would indicate that the heat shrink tubing can shrink to one-third the size of its expanded version.  Heat shrink tubing is available in a variety of ratios in order to address a high number of needs.

What can clients use heat shrink tubing for?

Heat shrink tubing is a highly-sought fluoropolymer product.  It can be applied to a wide variety of jobs including:

– Sealing water

– Insulating cables and wires against extreme cold and heat

–  Providing color-coded casings on wires

–  Harnessing multiple wires together

–  Eliminating the ends of braided sleeving

–  Improving the look of wires and cables when exposed to the naked eye

Use Heat Shrink Tubing for Many Applications

We are excited to introduce heat shrink tubing to join with our products including PTFE, FEP, PVDF tubing, and others.  The heat shrink tubing is made with TEFLON (a trademarked product of DuPont).  This provides the tubing with a memory capability.  Through the application of heat, the shrink tubing can activate its tenacious, memory aspect.

Fluorotherm’s heat shrink tubing can be engineered into a variety of shapes in order to conform to specific jobs.  We pride ourselves in producing premier products using high-quality resin.

Our heat shrink tubing has an upper use temperature of 400 deg F.  The corrosion resistant tubing protects housed parts from chemicals and mechanical wear.  The outer, seamless jacket is clear, electrically insulating, and is anti-stick, which provides premier weathering capabilities.

Like many of Fluorotherm’s products, our heat shrink tubing can be applied to many industries and specific jobs.  The tubing can be used for wire insulation, abrasion resistance, electrical protection, mechanical and water protection, and beyond.  Please consult us regarding our heat shrinking tubes for specific jobs desired.

At present, we are producing heat shrinking tubing in FEP, PTFE, and PFA.

Come to our Web page dedicated to heat shrink tubing to find out about particular sizing along with other statistics.