Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X20R
The AirTAC Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X20R 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, 20mm stroke; the return spring resets the rod when air is released.
- BoreØ8 mm
- Stroke20 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 PTBR8X20R
The AirTAC PTBR8X20R is a JIS pen-size single-acting pull cylinder with a 20mm stroke. Air entering the M5x0.8 port retracts the rod, while an internal spring pushes it back out. This provides 12.4N of net pull at 0.5 MPa (19.9N at 0.7 MPa), with the spring force already deducted.
It bolts directly to your fixture via the M4x0.7 front-cover thread, saving space in tight jigs. The SUS316L stainless barrel and fixed TPU bumper ensure durable operation. If air pressure drops, the spring keeps the rod extended for a safe fail-safe return.
Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X20R Technical Specifications
| Model | Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X20R |
|---|---|
| Series | PTBR JIS pen-size front-mount cylinder |
| Bore size | Ø8 mm |
| Rod diameter | Ø4 mm |
| Stroke | 20 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 PTBR8X20R
| PTBR | JIS pen-size front-mount single acting, pull type (spring extend) series. |
|---|---|
| 8 | Bore size in mm. |
| ×20 | 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 PTBR8X20R Is Used
Hold-Down Clamp
Pulls a small workpiece down against a fixture. The spring keeps the clamp safely open during air loss, preventing part damage.
Retract-to-Open Gate
Uses the M4x0.7 front thread to mount directly on a conveyor diverter. Air pulls the gate closed, and the spring extends it open on signal loss.
Light Tensioner
Applies steady tension to a film or wire in a packaging jig. The compact pen-size body fits tight spaces while delivering 12.4N pull.
Is the Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X20R the Right Cylinder?
This 8mm bore provides 12.4N net pull at 0.5 MPa. If you need less force, the 6mm bore offers 7.1N; for more power, the 10mm bore yields 23.5N. Plan for a safe working load of about 7N (roughly 60% of the 0.5 MPa rating) to account for seal friction and smooth travel. Vertically, it safely holds or pulls about 0.6kg with a 2:1 margin.
The direct M4x0.7 front mount eliminates separate brackets, and the R axial inlet keeps plumbing in line. The Ø4mm rod is built for coaxial thrust, so add an external guide if your application involves off-axis loads. Confirm the 20mm stroke and M5x0.8 air port fit your assembly.
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 PTBR8X20R FAQ
The net pull force is 12.4N at 0.5 MPa and 19.9N at 0.7 MPa (spring force already deducted). It requires a minimum operating pressure of 0.2 MPa to overcome the spring and retract the rod. If air is lost, the spring fails-safe to the extended position.
It mounts directly via the M4x0.7 thread on the front cover, with an R axial back cover for in-line air plumbing. This specific model does not include a sensor magnet. The SUS316L stainless barrel provides 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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