# PU Straight Union Fitting Push-to-Connect Tube Connector

Date: 2026-07-14
Categories: Pneumatic Fittings
URL: https://homipneu.com/pu-pneumatic-straight-union.html

## Product Summary

PU pneumatic fittings are **straight union push-to-connect connectors** designed for connecting two pneumatic tubes in a straight line within compressed air systems.

With a simple inline structure, PU fittings allow efficient tube extension and direct connection without changing direction, making them essential components in pneumatic pipelines and automation systems.

The push-to-connect design enables fast installation without tools, ensuring secure connection and leak-free performance in industrial applications.

**OEM and ODM customization services are available** for tube sizes, materials, sealing types, and branding requirements.

### Specification Parameters

**Operating Fluid**
Air

**Type**
Pneumatic Fittings

**Proof Pressure**
1.32 MPa (13.5 kgf/cm²)

**Max. Operating Pressure**
0~0.9 MPa (0~9.2 kgf/cm²)

**Ambient & Fluid Temperature**
0~60°C

**Applicable Tubing**
PU Tube, Nylon Tube

![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/04/20260428202443405555-800x440.webp)

**Model**
**ØD × 2**
**B**
**ØP× 2**

PU-4
4
32
11

PU-6
6
35.5
13

PU-8
8
37.5
15

PU-10
10
44
18.5

PU-12
12
47.5
21

PU-14
14
49
23.5

PU-16
16
53.5
25.5

### Color options available:

[![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/05/20260501201138041125.webp)](https://homipneu.com/wp-content/uploads/2026/05/20260501201138041125.webp)

[![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/05/20260501201134578955.webp)](https://homipneu.com/wp-content/uploads/2026/05/20260501201134578955.webp)

[![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/05/20260501201136478168.webp)](https://homipneu.com/wp-content/uploads/2026/05/20260501201136478168.webp)

![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/05/20260501201138041125.webp)

![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/05/20260501201134578955.webp)

![PU pneumatic straight union push to connect air tube connector](https://homipneu.com/wp-content/uploads/2026/05/20260501201136478168.webp)

### Key Features

- Straight union (tube-to-tube) design

- Push-to-connect quick installation

- Inline connection without direction change

- Leak-proof sealing with O-ring

- Reusable and easy disconnection

👉 Straight union fittings are used to connect two tubes in the same direction within pneumatic systems

### Applications

- Pneumatic automation systems

- Air compressor pipelines

- Industrial machinery

- Robotics systems

- Packaging and assembly equipment

Widely used in pneumatic systems requiring **inline tube extension, simple pipeline connection, and stable airflow transmission**.

### Product Function

PU fittings are designed to **connect two pneumatic tubes directly in a straight line**, allowing extension or repair of air pipelines without changing direction.

👉 Simple structure comparison:

- PU = straight union (tube ↔ tube)

- PC = tube ↔ thread

- PL = elbow (90°)

- PM = bulkhead straight

### Product Structure & Size Range

- PU4 / PU6 / PU8 / PU10 / PU12 / PU14 / PU16

- Tube sizes: 4mm → 16mm

- Equal union (same size both ends)

- Inline straight connection

### Why Choose Our Pneumatic Fittings

- Professional **PU pneumatic fitting manufacturer** with full size range

- OEM / ODM customization for **straight union push to connect fitting projects**

- Reliable **pneumatic tube connector for automation and compressed air systems**

- High-quality **air fitting factory China with strict QC system**

- Durable **push-in pneumatic fitting for stable airflow applications**

- Fast delivery and global B2B supply support

### FAQ

**Q1: What is a PU pneumatic fitting?**It is a straight union push-to-connect fitting used to connect two air tubes in pneumatic systems.

**Q2: What is a straight union fitting used for?**It is used to extend or connect tubing in a straight line without changing direction.

**Q3: How does a push-to-connect fitting work?**The tube is inserted into the fitting and locked by internal gripping teeth, while an O-ring provides sealing

**Q4: What is the working pressure of PU fittings?**Typical working pressure is 0–1.0 MPa depending on size and material

**Q5: Can PU fittings be customized?**Yes, OEM/ODM customization is available for size, material, and structure.