What Is PU Tubing?

Polyurethane tubing (PU tubing) is a commonly used piping material in industrial automation equipment and pneumatic systems. It is primarily applied for compressed air transmission and internal air supply connections within equipment.
Compared with other plastic tubing materials, PU tubing achieves a balanced material behavior between flexibility, bending stability, and consistency under dynamic operating conditions.
As a result, it is frequently used in piping locations where space is limited, bending is required, or relative movement occurs during equipment operation. These characteristics make PU tubing a standard pneumatic tubing option in automation systems.

Typical Application Scenarios of PU Tubing

In industrial and automation equipment, PU tubing is commonly used in the following pneumatic system configurations:

• Pneumatic modules, solenoid valves, and control system piping in automation equipment
• Internal air supply connections between pneumatic components within industrial compressed air systems
• Dynamic pneumatic piping layouts that involve bending or movement during equipment operation

In practical applications, the suitability of PU tubing for a specific system is not determined solely by the use of PU material. Proper selection requires further evaluation of the operating environment and the piping configuration.

Structural Categories of PU Tubing

PU tubing is commonly available in single-layer construction. However, depending on installation requirements and operating conditions, different structural designs may be selected.

• Single-layer PU tubing: Designed primarily for flexibility and dynamic bending requirements.
• Reinforced PU hose (three-layer construction): Incorporates a fiber reinforcement layer between the inner and outer PU layers to control radial deformation under working pressure conditions.

→ Further Reading | Reinforced PU Air Hose – Structural Design and Supply Forms

PU Tubing Material Structure: What Is the Difference Between ESTER and ETHER Types?

PU tubing exhibits different material behaviors depending on its polymer structure.
Differences between ESTER-type and ETHER-type PU tubing are mainly reflected in water resistance, long-term service stability, and applicable operating environments.

Comparison of ESTER-Type vs. ETHER-Type PU Tubing

PU tubing selection can be initially assessed based on operating environment conditions and piping layout requirements.
The differences between ESTER-type and ETHER-type PU tubing are summarized in the table above.

Further Reading

→ PU Tube FAQ — 15 Common Technical Questions by Automation Engineers

→ Pneumatic Tubing Selection for Non-Stop Production | An Engineering Guide

→ Air Tubing Configuration in Modern Poultry Processing Lines