Five Questions About Festo Tubing, Hoses, and the Mistakes I Made

Look, I'm not a design engineer. I'm the guy who handles procurement and maintenance for a mid-sized automation integrator. I've been doing this for about six years now, and I have a specific skill: I can make a $3,200 mistake in under five minutes. It's a talent.

So when we started getting more orders specifying Festo components, I thought I had it figured out. I didn't. I mixed up polyurethane and nylon tubing, used the wrong pliers, and even confused a flex hydraulic hose with a standard pneumatic air hose. It was a mess. So I put together this FAQ from my own screw-ups. If you're a buyer, a maintenance tech, or just someone trying to figure out the Festo website without pulling your hair out, this is for you.

1. Polyurethane vs Polyethylene Foam: Why do I keep seeing these compared for tubing?

Short answer: They aren't really compared for tubing. It's a search term mix-up.

Honestly, this one tripped me up for a minute. When I first started searching, I saw "polyurethane vs polyethylene foam" and thought, "Great, I need to choose between these for my air lines." Wrong. Polyethylene foam is a completely different thing—it's used for packaging, insulation, gaskets. It's not a pneumatic material.

What you need to compare for Festo tubing is polyurethane (PU) and nylon (polyamide). These are the two workhorses for motion control. Polyurethane is super flexible and abrasion-resistant, like the Festo PUN series. Nylon, like the Festo PUN-H or standard nylon, is stiffer and holds its shape better in high-heat environments. I only figured this out after ordering a spool of what I thought was "flexible nylon" (doesn't exist) and ending up with a useless roll of packing material. Not my finest hour.

2. Which is better for my application: Festo nylon tubing or Festo polyurethane tubing?

That depends on what you're trying to do. I learned this the $890 way.

In my first year (2017), I ordered a batch of Festo nylon tubing for a robot arm that needed to flex constantly. The tubing was too stiff. It kinked, it fatigued, and after three months, it cracked at the fitting. The replacement cost plus labor was about $890. It was a disaster.

So here's the cheat sheet I now use:

  • Use Polyurethane (PUN): If your application is dynamic (moving parts, robotic arms, tight bends). It's flexible, it resists kinking, and it's tough. Think of it like a durable rubber band—but way better.
  • Use Nylon (PUN-H or Standard): If you need high pressure resistance, high temperature stability (like near ovens), or a rigid line for static applications. It's like a stiff straw that won't collapse.

The mistake I see other new guys make? Going for nylon because it's cheaper per foot. But the total cost can be way higher if you get it wrong. I learned that lesson.

3. I need a 'flex hydraulic hose.' Can I use Festo pneumatic tubing instead?

No. Absolutely not. I almost did, and it was a close call.

Here's the thing: I was rushing a project in September 2022. We had a leak in a low-pressure hydraulic line, and I had a spool of Festo tubing right there. My brain said, "It's just oil. Tubing is tubing." Wrong.

A flex hydraulic hose is built for high pressure and specific hydraulic fluids. It has multiple layers of reinforcement—like a braided steel core. Pneumatic tubing, even the tough polyurethane stuff, is not rated for that. It can swell, burst, or just fail catastrophically. It was a good thing I stopped and actually checked the pressure rating. The potential for a machine crash or a serious injury was very real. A flex hydraulic hose from a specialist (Gates, Parker) is a completely different product class.

4. Why do I need special 'nylon pliers'? Aren't they all the same?

No. Standard pliers will shred your fittings. I killed a $450 order this way.

I only believed this advice after ignoring it. I had a small order of Festo push-in fittings. I used standard needle-nose pliers to pull a jammed tube out of a fitting. I thought, "It's just a little tug." I scratched the internal brass collet, and the fitting never sealed properly again. The order—about $450 worth of fittings—was trash. Embarrassing.

Nylon pliers (or plastic jaw pliers) are specifically designed not to mar the surface of your fittings. They're softer than metal, so they grip without scratching the precision sealing surfaces. If you're working with Festo fittings, just spend the $15 on a pair of nylon pliers. It's cheaper than one mistake. I keep a pair in my tool drawer specifically for this.

5. I can't find the spec sheet. How do I navigate the Festo website and catalog?

Use the Festo login and support portal. It's not as hard as you think.

I completely get why people get frustrated with the Festo website. There are so many catalogs and part numbers. But the trick is using the Festo Support Portal. You need a Festo login (it's free to create). Once you're in, you can do two things:

  1. Search by part number directly. Type in a part number like `CRDSNU-32-400-PPS-A` and you get the exact manual, data sheet, and 3D CAD file.
  2. Use the product finder. If you don't have a part number, describe what you need (e.g., "nylon tubing 8mm OD"). It's pretty intuitive.

The mistake I made early on? I tried to use Google search for everything. I'd end up on outdated distributor pages. Now, if I need something from Festo, I go directly to their website and use the support portal. It saves me hours. As of 2025, this is the fastest method. Things may change, but for now, it's the gold standard.