Pneumatic cylinder
CU compact pneumatic cylinder
CU compact pneumatic cylinder
Specifications
- Material
- Aluminum alloy
- Operation pressure
- 0.1-0.9Mpa
- Working Medium
- Air
- Working temperature range
- -5-60 degree
CU Series Compact Free-Mount Pneumatic Cylinder
The CU Series Compact Pneumatic Cylinder is a space-saving linear actuator designed for automation equipment where a conventional cylinder would occupy too much installation space.
Its rectangular body can be mounted directly from multiple surfaces, helping simplify machine design and eliminate the need for large external mounting brackets. Bore sizes from 6 mm to 32 mm and strokes up to 50 mm make the CU Series suitable for short-distance pushing, pulling, clamping, ejecting, stopping and positioning operations.
The series includes standard and magnetic versions, normal and non-rotating piston rods, and double-acting, single-acting pull-in and single-acting push-out configurations.
Key Features
Compact Rectangular Body
The short and low-profile body reduces overall machine size and makes the cylinder suitable for installation inside compact mechanisms, fixtures and tooling plates.
Free-Mount Installation
The cylinder body provides multiple mounting possibilities. Depending on the selected model and application, it can be installed from different surfaces without a large separate mounting bracket.
This design helps:
- Reduce the number of mounting components
- Simplify equipment design
- Save installation space
- Shorten assembly time
- Improve cylinder positioning flexibility
Six Bore Sizes
Available cylinder bores include:
- 6 mm
- 10 mm
- 16 mm
- 20 mm
- 25 mm
- 32 mm
This range covers miniature automation tasks as well as applications requiring greater output force.
Three Action Types
The CU Series is available in three operating configurations:
- Double acting
- Single acting, spring return or pull-in
- Single acting, spring extend or push-out
The correct action type can be selected according to the machine’s pneumatic circuit, required fail position and available air supply.
Optional Magnetic Piston
The CDU version is equipped with a magnetic piston for use with external auto switches.
Position sensing can be used for:
- Extended-position confirmation
- Retracted-position confirmation
- PLC input signals
- Machine-sequence control
- Cycle monitoring
- Interlocking
- Abnormal-position detection
Optional Non-Rotating Piston Rod
The K version incorporates a non-rotating piston-rod structure. It is suitable for applications where the attached workpiece or tool must maintain its angular orientation during extension and retraction.
The catalog specifies non-rotation accuracy of:
- Up to ±0.8° for applicable smaller bore models
- Up to ±0.5° for applicable larger bore models
The exact value should be confirmed for the selected bore and configuration.
Rubber Bumpers
Rubber bumpers help reduce direct internal impact at the end of the piston stroke.
The catalog identifies buffering at both ends for standard configurations. For the 6 mm bore single-acting magnetic version, only one side uses a rubber bumper.
Non-Lubricated Operation
The CU Series is designed for non-lubricated operation, simplifying air preparation and routine maintenance.
Technical Specifications
Item | Specification |
Product series | CU/CDU |
Cylinder type | Compact free-mount pneumatic cylinder |
Bore sizes | 6, 10, 16, 20, 25 and 32 mm |
Working medium | Compressed air |
Action types | Double acting, single acting push-out or single acting pull-in |
Proof pressure | 1.05 MPa |
Approximate proof pressure | 10.5 kgf/cm² |
Maximum operating pressure | 0.7 MPa |
Approximate maximum pressure | 7.1 kgf/cm² |
Minimum operating pressure | Depends on bore and action type |
Ambient and medium temperature without auto switch | -10°C to +70°C |
Ambient and medium temperature with auto switch | -10°C to +60°C |
Freezing | Not permitted |
Lubrication | Non-lubricated |
Piston-speed range | 50–500 mm/s |
Cushioning | Rubber bumper |
Piston-rod end | Male thread |
Rod-thread tolerance | Class 2 |
Stroke-length tolerance | +1.0/0 mm |
Non-rotating accuracy | ±0.8° or ±0.5°, depending on size |
Port size, 6–25 mm bore | M5 × 0.8 |
Port size, 32 mm bore | G1/8 |
The proof-pressure rating is used for product testing and should not be treated as the cylinder’s normal continuous operating pressure.
Minimum Operating Pressure
Minimum operating pressure depends on the bore and action type.
Bore Group | Single-Acting Type | Double-Acting Type |
6 and 10 mm | 0.20 MPa | 0.12 MPa |
16 and 20 mm | 0.15 MPa | 0.06 MPa |
25 and 32 mm | 0.13 MPa | 0.05 MPa |
The actual pressure required in a machine may be higher because of load, friction, installation direction, speed and system pressure loss.
Air Port Selection
Cylinder Bore | Port Size |
6 mm | M5 × 0.8 |
10 mm | M5 × 0.8 |
16 mm | M5 × 0.8 |
20 mm | M5 × 0.8 |
25 mm | M5 × 0.8 |
32 mm | G1/8 |
Make sure the pneumatic fitting thread matches the cylinder port exactly. Do not force an incompatible fitting into the port.
Standard Stroke Options
All stroke values are in millimetre.
Double-Acting Cylinders
Bore Size | Standard Strokes |
6 mm | 5, 10, 15, 20, 25, 30 |
10 mm | 5, 10, 15, 20, 25, 30 |
16 mm | 5, 10, 15, 20, 25, 30 |
20 mm | 5, 10, 15, 20, 25, 30, 40, 50 |
25 mm | 5, 10, 15, 20, 25, 30, 40, 50 |
32 mm | 5, 10, 15, 20, 25, 30, 40, 50 |
Single-Acting Cylinders
Bore Size | Standard Strokes |
6 mm | 5, 10, 15 |
10 mm | 5, 10, 15 |
16 mm | 5, 10, 15 |
20 mm | 5, 10, 15 |
25 mm | 5, 10, 15 |
32 mm | 5, 10, 15 |
Non-standard stroke requirements should be technically confirmed before ordering.
Frequently Asked Questions
What is a CU free-mount cylinder?
It is a compact rectangular pneumatic cylinder designed to be mounted directly from multiple body surfaces. Its shape helps reduce installation space and mounting complexity.
What is the difference between CU and CDU?
CU is the standard version. CDU includes a magnetic piston for use with an external auto switch.
What bore sizes are available?
The available bore sizes are 6, 10, 16, 20, 25 and 32 mm.
Is the CU cylinder double acting?
Double-acting, single-acting pull-in and single-acting push-out versions are available.
What does the K code mean?
K identifies the non-rotating piston-rod version.
What is the maximum operating pressure?
The specified maximum operating pressure is 0.7 MPa.
What is the proof pressure?
The proof-pressure rating is 1.05 MPa. This is a test value, not the recommended continuous operating pressure.
What is the operating-temperature range?
Without an auto switch, the specified temperature range is -10°C to +70°C. With an auto switch, it is -10°C to +60°C. Freezing is not permitted.
Does the cylinder require lubrication?
No. The catalog identifies the CU Series as non-lubricated.
What is the maximum piston speed?
The specified operating-speed range is 50–500 mm/s.
Does the cylinder have adjustable cushioning?
No adjustable air cushion is listed. The cylinder uses rubber bumpers.
What standard strokes are available?
Double-acting models are available in strokes from 5 to 30 mm for smaller bores and up to 50 mm for the 20, 25 and 32 mm bores. Standard single-acting strokes are 5, 10 and 15 mm.
What are the port sizes?
Models with 6–25 mm bore use M5 × 0.8 ports. The 32 mm bore version uses G1/8 ports.
Does the non-rotating version support side loads?
It limits piston-rod rotation but does not replace an external guide. Significant side loads and moments must be supported separately.
Are auto switches included with CDU cylinders?
The magnetic piston allows switch installation, but the supplied document does not specify whether switches are included. Confirm the switch model and quantity when ordering.
Can the cylinder use water, oil or other gases?
The specified working medium is compressed air. Other media require separate verification of material and seal compatibility.
