Polyvinyl Chloride (PVC) vs. Thermoplastic Rubber (TPR) vs. Polyurethane (PU) Hose

At Flexaust, we are a supplier of durable and reliable hose for industrial and commercial applications. Our hose offerings include polyvinyl chloride (PVC) hoses, thermoplastic rubber (TPR) hoses, and polyurethane (PU) hoses, all of which demonstrate different temperature range, abrasion resistance, and wall thickness requirements that make them a good, better, and best fit for different applications. In the following article, we discuss these three hose options and the applications for which they are best suited.

How to Choose the Right Hose Material

When selecting a hose material for a particular application, it is important to consider its performance in the short-term and long-term. For example, the ideal material should accommodate the environmental and operating conditions (e.g. heat, extreme cold, etc.) now and in the future. Below we outline how PVC, TPR, and PU measure up in these capacities.

PVC Hose: The Good Option

PVC hoses are an economical option for general-purpose applications. They are typically used in ventilation, woodworking, and other operations that do not involve exposure to extreme temperatures, chemicals, UV radiation, or abrasive materials.

Thermoplastic Rubber (TPR) Hose: The Better Option

Compared to PVC hoses, TPR hoses offer greater abrasion resistance and smoother interior assuring minimal friction loss and efficient airflow. They are suitable for use in applications that involve low or high temperatures, chemicals, moisture, and outdoor use (UV exposure).

Polyurethane (PU) Hose: The Best Option

Compared to PVC and TPR hoses, PU hoses serve as a superior solution for a wide range of industrial and commercial applications. In addition to being the most versatile hose because of its manufacturing capabilities–Flexaust has the ability to manufacture five wall thickness and static dissipative hose versions–PU hoses have great abrasion and chemical resistance, higher tear strength, better vacuum and pressure ratings, and good flexibility in low temperatures.

Common Applications of the PVC, TPR, and PU Hoses at Flexaust

Our hoses are suitable for many industrial and commercial applications. Below we outline some of the operations in which our hoses are regularly utilized for and which PVC, TPR, and PU hoses are viable options.

Woodworking

For woodworking applications, we recommend the following hoses:

Compared to R-4 and T-7, Flx-Thane MD offers good compressibility and superior abrasion resistance to handle anything from dust collection to larger more abrasive woodchips. The clear version is manufactured with FDA acceptable materials and is easy to detect any blockages in the hose while in service. Flx-Thane MD is also available in metric sizes, so it is compatible with European equipment.

Plastic Manufacturing (Blown Film Manufacturing)

For plastic manufacturing applications, we recommend the following hoses:

  • A good option: CWGP
  • A better option: T-7
  • The best option: T-7SR

While CWGP (made from double-ply neoprene coated polyester fabric) and T-7 (made from thermoplastic rubber) offer good performance in these operations, T-7SR provides even better performance and a higher temperature range which can be critical in this application depending on equipment used.

These thermoplastic rubber-coated woven polyester fabric hoses are reinforced with a spring steel wire helix offering better tensile strength and puncture resistance than traditional reinforced woven neoprene and TPR hoses. T-7SR demonstrates superior chemical, moisture, temperature, and UV resistance, as well as suitability for demanding positive and negative pressure environments.

Street Sweeping

For street sweeping applications, we recommend the following hoses:

While street sweeping equipment can operate with HT or Flx-Thane MD, Flx-Thane HD is ideal. The .045” wall thickness is heavier than HT and Flx-Thane MD making it a great choice for severe service applications like street sweeping. It has better puncture resistance and excellent flexibility, all of which are important in applications involving constant movement.

Leaf Collection

For leaf collection applications, we recommend the following hoses:

LCDC and HT-W are good options for leaf collection equipment. LCDC is a medium weight economical truck loader vacuum hose offering a long flex life, while HT-W has a heavier wall thickness and great moisture and UV resistance – also ideal for commercial landscaping. However, Flx-Thane HD is even better. It offers superior abrasion resistance, tear strength, and great moisture and UV resistance making it the best option.

Confined Space Ventilation

For confined space ventilation applications, we recommend the following hoses:

FX-400 is the superior solution here. It handles a wider temperature range which is critical when used for commercial and residential work area heating, cement drying, and event tents. The high strength sewn construction of FX-400 allows for better performance in low and high temperatures.

Every Wonder What’s Inside a Flexible Metal Hose? Hose Master Has an Answer

What Makes Up a Flexible Metal Hose?

In order to understand flexible metal hose assemblies and how they serve various applications it’s best to review their anatomy. In its simplest form, a metal hose is made of four basic components:

    • Corrugated tubing
    • Braid
    • Braid collars
    • End-fittings

Separately, these parts are really quite simple. However, they can be customized to form a variety of configurations, enabling flexible metal hoses to be an optimal solution in a number of industries.  Let’s examine each of these components individually and discuss how they all work together to create value.

Corrugated Tubing

The corrugated tubing is the core component of a flexible metal hose. Not only does it comprise the bulk of an assembly, but it also plays a part in key value-added attributes of the assembly, such as corrosion resistance, pressure rating, and flexibility.

Corrosion Resistance

Corrosion resistance is simply a matter of selecting the correct alloy for the media that is being conveyed. For most applications, 321 stainless steel provides sufficient corrosion resistance. If additional chemical resistance is needed, 316 stainless steel can be used, which contains more nickel and other alloying elements to increase chemical resistance. Chlorine transfer applications require the highest degree of corrosion resistance. For chlorine and other highly-critical applications, C276 may be the best choice.

Pressure Rating

Pressure rating (also referred to as “maximum allowable working pressure” or “MAWP”) is the term use to express the ability of a hose to handle internal pressure. At Hose Master, the pressure ratings of our hose is determined by conducting various pressure testing in our in-house Product Analysis Lab.

The pressure rating that “creates value” for an assembly depends on the application in which the assembly is going to be used. For many standard applications, a hose with a lower pressure rating can be used, whereas more critical applications may demand the use of a hose that can withstand higher pressures.

Flexibility

Flexibility can mean different things to different people. To some, it may refer to a hose’s ability to be bent into a tight radius. To others, it may mean a hose has a high cycle life. Or, it may mean that a hose will bend easily without exerting high spring forces on the surrounding equipment.  Fortunately, there is some flexibility allowed in this definition thanks to Hose Master’s proprietary forming processes, which create metal hose that provides all three of these qualities.

For corrugated metal hose, flexibility is expressed by the “minimum dynamic bend radius” (MDBR), which is derived through testing in our in-house lab. Depending on the application, a larger MDBR may be acceptable or a tighter MDBR may be required.  If an application requires a tighter MDBR, then a close-pitched hose would provide a valuable solution. Close-pitched hoses feature more corrugations per foot than standard hose, which distributes the bending stresses over more corrugations and allows the hose to be bent more tightly.

Braid

The second component of metal hoses is the braid. Along with hose selection, the braid contributes to an assembly’s ability to withstand high pressures.

There are multiple factors that can contribute to the functionality of the braid, such as the wire diameter, the number of wires per carrier, the number of carriers on the braiding machine and the percentage of braid coverage. The pressure rating of a hose may also be increased by adding additional layers of braid or using braided braid. Proper braid design has a significant effect on the working pressure and cycle life of the hose. Utilizing a braid package with a high-percentage braid coverage that is braided directly onto the hose helps to ensure that the braid is well-secured on the hose, protecting the assembly from potential deformation and ensuring maximum cycle life.

Braid Collars

While only accounting for a small portion of a hose assembly, the braid collars have an important role. Braid collars serve to join the inner corrugated hose and the braid together during the cap welding process, in which a TIG weld joins the hose, braid and braid collar together into the cap weld bead. This cap weld needs to be perfect, as it will be the base for the subsequent attachment weld and is the connection point holding all of the components of the hose together.

Along with helping join the hose components together, the braid collars also serve to protect and isolate the corrugations near the cap weld from any movement. After the cap welding process, these corrugations are now a “heat-affected zone” and are thus unable to functionally cycle with the rest of the hose. The braid collars ensure that any bending stresses are properly distributed over the right corrugations, preserving the cycle life of the assembly.

End-Fittings

The final component added to an assembly is the fittings. There are a lot of options available when it comes to fittings selections, allowing flexible metal hose assemblies to be customized to fit into a variety of applications. Therefore, it is important that the fittings selected fit the needs of the application. Be sure to verify the size, alloy, and pressure requirements of an application before making a definitive fittings selection.

Designing a Flexible Metal Hose Assembly: Creating Value

Ultimately, what creates value for a flexible metal hose assembly comes down to the specific demands of each application.  No matter the complexity, Hose Master’s skilled engineering staff and dedicated customer support personnel are able to supply not only exceptional quality in each assembly, but stellar service, resulting in the greatest value for our customers. For more information on Hose Master’s solutions contact us at (216)-481-2020 or visit us online and we’d be happy to assist you.

 

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