Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR
The AirTAC Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR is a single acting, pull type (spring extend) pen-size mini cylinder with direct front-cover mounting (M4×0.7 thread). A single air port drives the pull stroke on a Ø8mm bore, 25mm stroke; the return spring resets the rod when air is released.
- BoreØ8 mm
- Stroke25 mm
- Port sizeM5×0.8
- Front-mount threadM4×0.7
- Acting typePull, single acting
- ReturnSpring
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR
The AirTAC PTBR8X25SR is a JIS pen-size single-acting pull cylinder. Air entering the M5x0.8 port retracts the rod, while releasing air lets the spring push it back out. This provides a fail-safe extended state during air loss, ideal for holding parts safely. It delivers 12.4 N of net pull at 0.5 MPa.
You bolt this actuator straight to a fixture via the direct M4x0.7 front-cover thread. The SUS316L stainless barrel resists corrosion, and a fixed TPU bumper cushions the stroke ends. The built-in magnet supports reed or electronic switches for position sensing.
Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR Technical Specifications
| Model | Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR |
|---|---|
| Series | PTBR JIS pen-size front-mount cylinder |
| Bore size | Ø8 mm |
| Rod diameter | Ø4 mm |
| Stroke | 25 mm |
| Acting type | Single acting, pull type (spring extend) |
| Front-mount thread | M4×0.7 |
| Port size | M5×0.8 |
|---|---|
| Operating pressure | 0.2 – 0.7 MPa |
| Proof pressure | 1.2 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 50 – 800 mm/s |
| Return | Return spring (pull by air) |
| Max standard stroke | Up to 60 mm |
The spring holds the rod extended; applying air retracts it, and removing air lets the spring push the rod back out. Front cover carries the mounting thread (M4×0.7); barrel is SUS316L. Forces below are NET spring-deducted values. Confirm against the product label.
Net Pull Force (Ø8mm)
| Pressure | Net pull force |
|---|---|
| 0.5 MPa | 12.4 N |
| 0.7 MPa (max) | 19.9 N |
These are usable pull forces after the return spring is subtracted, from the AirTAC single-acting thrust table. Minimum operating pressure is set by the spring, so this model needs at least the lower pressure shown to move.
Model Code: Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR
| PTBR | JIS pen-size front-mount single acting, pull type (spring extend) series. |
|---|---|
| 8 | Bore size in mm. |
| ×25 | Stroke length in mm. |
| S | Built-in magnet for magnetic-switch position sensing (omit = no magnet). |
| R | Back cover: R axial inlet (bore-dependent). |
Mounting: direct front-cover thread (M4×0.7). Related PBR-family variants: PBR (double acting), PSBR (single-acting push).
Where the Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR Is Used
Fail-Safe Hold-Down Clamp
Keeps a workpiece clamped by spring pressure if air drops, using the pull stroke to release the part only when pressured.
Retract-to-Open Gate
Holds a sorting gate closed via spring force, pulling it open momentarily to divert items on a packaging line.
Light Tensioner
Maintains steady tension on a filament or wire, retracting to slacken the line when compressed air is applied.
Is the Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR the Right Cylinder?
This 8mm bore provides 12.4 N net pull at 0.5 MPa and 19.9 N at 0.7 MPa. If you need less force, the 6mm bore offers 7.1 N at 0.5 MPa. For heavier loads, the 10mm bore yields 23.5 N.
The spring requires a minimum 0.2 MPa pressure to move. The Ø4 mm rod is built for coaxial thrust, so add an external guide for off-axis loads. Confirm your M4x0.7 front-mount thread engagement and specify the R axial inlet back cover when ordering.
Quick checklist
- ✓ Net pull force at your working pressure
- ✓ Bolt directly through the front cover (M4×0.7)
- ✓ Only one air line / solenoid needed
- ✓ Fail-safe extend on air loss
- ✓ Magnet (S) for sensors?
- ✓ Stroke ≤ 60 mm (single-acting limit)
Installation & Maintenance Notes
- check Use clean air filtered to 40µm or finer.
- check Keep within 0.2 – 0.7 MPa operating pressure.
- check Allow for spring force in the stroke direction.
- check Match bolt size and engagement to the front thread.
- check Do not add an external return mechanism.
- check Keep the load coaxial; avoid side load on the thin rod.
Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X25SR FAQ
It provides 12.4 N net pull at 0.5 MPa and 19.9 N at 0.7 MPa. Because it is spring-extended, it requires a minimum 0.2 MPa to overcome the spring and retract the rod. If air is lost, the spring pushes the rod out to a fail-safe extended position.
It mounts directly via the M4x0.7 thread on the front cover, eliminating separate brackets. The S denotes a built-in piston magnet compatible with reed or electronic solid-state switches. The SUS316L barrel provides excellent corrosion resistance.
Authorized Export Seller
Genuine AirTAC parts produced by AirTAC factory.
1-Year Warranty
Covers non-human-caused product damage.
Fast Dispatch
Standard models are processed and dispatched in 3-5 business days.
Fast Reply
Most inquiries answered within 7-8 hours.
Related AirTAC PTBR Pen-Size Cylinders
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