Taking Tube Bending to the Next Level
During the last two decades, Axenics’ dedication to plastic tube bending resulted in methods and finished products like plastic tube assemblies that cannot be found elsewhere. We won’t give too much away about our proprietary plastic tube bending and tooling techniques, but these efforts have been a boon for engineers in the semiconductor and medical device manufacturing industries, where ultra-high purity grades of plastics are crucial to avoid contamination.
We focus on synthetic fluoropolymer tubes with our plastic tube bending projects. Wikipedia has a great definition of fluoropolymers: They are characterized by high resistance to solvents, acids and bases. The best known fluoropolymer is polytetrafluoroethylene also known by its brand name, Teflon. At Axenics, we focus on these fluoropolymers:
- Perfluoroalkoxy (PFA)
- Polytetrafluoroethylene (PTFE)
- Fluorinated Ethylene Propylene (FEP)
These fluoropolymers are ideal for the transfer of solvents, chemicals, corrosives and cryogenics due to their high-heat resistance, aging resistance and non-stick attributes.
- Raw fluoropolymers can be FDA, REACH, RoHS and USP Class Vi compliant
- Chemically inert
- Low coefficient of friction
- Low permeability
What are the differences between PFA, PTFE and FEP?
PFA tubing has stronger heat resistance than FEP, and offers more flexibility than PTFE.
We use PTFE in many semiconductor and medical device manufacturing projects due to its high chemical resistance, capabilities in high and low temperatures capability, top-notch gas and vapor permeability, and that it is known for having the lowest coefficient of friction of any solid material.
FEP tubing is also known for its gas and vapor permeability, but FEP offers a lower heat shrink temperature versus PTFE and is more flexible than PTFE. Raw FEP is the lowest-cost option of these three.
Typically, manufacturing engineers determine what materials and processes are necessary to get to their end result, however, our input during the design stage sometimes determines what will best serve your needs.
Determining the right plastic for you
We can provide whatever results you need with fluoropolymer tube bending, but the exact plastic used depends on the temperature of your production environment. You don’t want a thermoplastic to relax due to extreme heat, which can weaken your system with cracks, fissures or tube breaks.
PTFE is Axenic’s top plastic for customers partly due to its high fire rating, meaning it doesn’t melt when it gets exposed to higher temperatures. That’s important to our customers in the semiconductor and medical device manufacturing industries as the environment in which the PTFE tubing is in use could heat significantly with multiple pieces of equipment in action in a closed space. There may be pumps and motors running near the tubing, and the heat from those machines won’t cause the PTFE to crack or alter its innate properties.
In-house fluoropolymer forming happens on tubing ranging from ⅛-inch up to 1-inch. Bonding (usually with PFA) is performed on ¼-inch to 2-inch pipe, though we have worked on larger diameters when needed.
Axenics’ unique plastic tube bending process
Over years of experimentation, we developed plastic tube bending equipment and techniques that perform better than what many technicians consider “standard tube bending.” The techniques and tooling exclusive to Axenics allow us to achieve tighter tolerances and accomplish more modifications than with conventional tooling and procedures.
At Axenics, consistency is key, as some customers order thousands of the same plastic tube kits per year, and each kit must be exactly the same as the last, completely repeatable.
Fortunately, after years of perfecting them, our in-house plastic tube bending procedures allow for fast and straightforward training of new technicians, meaning big jobs aren’t held up.
Our techniques and tooling allow us to achieve unique challenges presented by engineers in the fields of semiconductor manufacturing and medical device manufacturing.
Axenics also has the capability of developing plastic tube bending tooling based on your specific needs, such as extremely tight tolerances. Through our procedures, we’ll develop equipment to achieve the exact bend radius, angle and design for your project.
Testing your plastic tube assemblies
The tubing is visually inspected multiple times throughout the project, starting with inspecting for blemishes, a fleck of plastic that got trapped inside the tube or any fault that can cause a problem. We’ll reject entire raw plastic lots if needed. We measure the diameter of each bend. We test for heat resistance and timing to ensure your tubing is flawless when it arrives for your production.
Once the plastic tube bending procedure is complete, we perform a nitrogen pressure test to ensure all the joints hold. Before every tube goes out, they’re inspected, to ensure there are no scratches or anything that would cause problems.
We see an increased demand for bent plastic tubing for medical device and semiconductor manufacturing productions, as the process eliminates more joints and fittings, allowing a seamless flow through the tubing. You can practically eliminate the chance of contamination or hang ups through the transportation process with our unique tube bending process.
Perfection in precision tube bending requires both the inside and outside diameter to have zero imperfections. It’s a skill we’ve honed for four decades.