Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X50SR
The AirTAC Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X50SR 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, 50mm stroke; the return spring resets the rod when air is released.
- BoreØ8 mm
- Stroke50 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 PTBR8X50SR
The AirTAC PTBR8X50SR is a single-acting pull pen cylinder with a 50mm stroke and 8mm bore. Air entering the M5x0.8 port retracts the rod, while a spring extends it out. This fail-safe extended behavior keeps the rod out on air loss, making it ideal for tensioning or return-to-home tasks. It delivers about 12.4 N net pull at 0.5 MPa.
The SUS316L stainless barrel houses a slim pen-size body for tight jigs. It bolts directly via the front-cover M4x0.7 thread, requiring no extra bracket. A fixed TPU bumper cushions the end of travel. The built-in magnet (-S) supports reed or electronic switches, and the R axial inlet keeps plumbing in line.
Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X50SR Technical Specifications
| Model | Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X50SR |
|---|---|
| Series | PTBR JIS pen-size front-mount cylinder |
| Bore size | Ø8 mm |
| Rod diameter | Ø4 mm |
| Stroke | 50 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 PTBR8X50SR
| PTBR | JIS pen-size front-mount single acting, pull type (spring extend) series. |
|---|---|
| 8 | Bore size in mm. |
| ×50 | 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 PTBR8X50SR Is Used
Hold-Down Clamp
Uses spring pressure to hold a part extended, then air pulls the clamp back to release the workpiece.
Retract-to-Open Gate
Air retracts the rod to open a small diverter gate, with the spring failing safe to the closed position.
Wire Tensioner
Maintains steady tension on a filament or wire line, pulling back only when air pressure is applied.
Is the Airtac PTBR Single Acting Square Head Compact Cylinder PTBR8X50SR 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 yields 7.1 N at 0.5 MPa. For heavier loads, step up to the 10mm bore for 23.5 N.
The spring requires a minimum 0.2 MPa to move. The thin Ø4 mm rod suits coaxial thrust over this 50mm stroke; add an external guide for off-axis loads. The fixed TPU bumper only decelerates the last few mm, so meter-out the exhaust if moving real tooling mass at mid speed. Confirm the M4x0.7 front-mount thread engagement 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 PTBR8X50SR FAQ
It delivers 12.4 N net pull at 0.5 MPa and 19.9 N at 0.7 MPa. Because it is single-acting pull, a minimum of 0.2 MPa is required to overcome the spring and retract the rod. If air is lost, the spring pushes the rod out to a fail-safe extended state.
It mounts directly via its front-cover M4x0.7 thread, separate from the M5x0.8 air port. The -S suffix denotes a built-in piston magnet compatible with AirTAC reed or electronic solid-state switches. The SUS316L 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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