Many custom plastic extrusion companies offer flexible and rigid plastic extrusion parts. Which one is right for you is always an interesting question that requires some research and thought.
Let’s look at each part – flexible and rigid – and see how they are commonly used.
Flexible Plastic Tubing
Generally, flexible plastic tubes are used where the plastic needs to bend to fit a particular use.
When speaking of flexible plastic tubing, there are two common materials: Polyvinyl Chloride [PVC] or Polyurethane [TPU]. PVC is widely used in the industry and typically is the lowest cost material. Polyurethane is better suited for certain applications, typically involving wear, than Flexible PVC.
PVC vs Polyurethane
Let’s examine the differences between the two in more detail.
PVC [or in this case FPVC] is the most popular flexible plastic extrusion tubing material for a reason. It has rubber-like flexibility [although it can be made to be rigid.] It allows for outstanding liquid flow. And it offers a broad range of chemical and corrosion resistance as well as solid abrasion and wear resistance.
Additionally, PVC plastic has numerous construction options such as spiral, wire or cord reinforcement or unreinforced tubing.
Industries that use PVC tubing:
- Food and beverage
- Cleaning apparatus
- Pool and spa
A PVC plastic tubing downside is that it can harden and crack when used to move certain liquids, such as concentrated acids and alkalis. Also, flexible PVC is made with an additive plasticizer, which over time gets sticky and gummy.
Unlike PVC, Polyurethane has no plasticizers added to its composition. It combines the best characteristics of plastic and rubber, which allows for tremendous natural flexibility and is abrasion resistant.
Like PVC, Polyurethane has its issues. Depending on its composition properties, which can vary, certain polyurethane plastics do better – or worse – than others depending on its usage. Ether based TPU’s are preferred if the product is to be submerged or used in a very humid environment. Ester based TPU’s work best if the product comes in contact with oils, fuels, or solvents.
Most common applications for polyurethane plastic tubing include:
- Cable jacketing
- Pneumatic control systems
- Air lines
- Powder and granular material transfer
- Fluid line
- Low pressure hydraulics
- Food and beverage
Rigid Plastic Tubing
Rigid plastics are as advertised hard and inflexible and mostly used in external environments. They are often used as a cheaper alternative to metal, or more expensive materials.
Rigid plastics can be made with a variety of materials. They include:
Rigid PVC [or RPVC] can be easily extruded into weather resistant, high tensile and impact resistant plastic that makes it ideal in a number of industries. They include:
- Electrical equipment
- Construction products
Where Should You Buy Your Flexible or Rigid Plastics?
The best thing to do when you are undecided in what type of plastic you need for your project is to find an experienced and reputable manufacturer.
In addition to helping you decide which type of plastic is best for you, you’ll want a manufacturer that offers a variety of options and choices.
For instance, what materials do they offer that can work in your application? Can they provide long lengths of plastic? Can it be spooled or wound on a reel? Since flexible plastics can range from very flexible – 60a – to almost but not quite rigid – 95a – you’ll want a manufacturer that has the capability to machine exactly the type and consistency of plastic that will work best for you.
Once you find the right company you can then develop a long-lasting relationship which will make your future plastics tubing buying an easier and less stressful process.