Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S
The AirTAC Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S is a double-acting, double-rod pen-size mini cylinder whose rear rod carries a stroke adjuster. On a Ø12mm bore it gives a nominal 125mm stroke with a 40mm fine-adjustable window — settable from 85 to 125mm, so you set the end position without changing hardware.
- BoreØ12 mm
- Nominal stroke125 mm
- Adjust window40 mm
- Effective range85–125 mm
- Port sizeM5×0.8
- Acting typeDouble acting
- 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 PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S
The AirTAC PBJ12X125-40S is a double-acting, double-rod pen-size mini cylinder with a 40 mm adjustable window. A rear M5x0.8 adjuster screw shortens the retract end, giving an effective stroke range of 85-125 mm from the nominal 125 mm. The extend end remains fixed.
The SUS304 stainless slim body saves space in tight jigs. It includes a built-in piston magnet for position sensing and a fixed TPU bumper at each end.
Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S Technical Specifications
| Model | Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S |
|---|---|
| Series | PBJ JIS pen-size adjustable-stroke cylinder |
| Bore size | Ø12 mm |
| Rod diameter | Ø5 mm |
| Nominal stroke | 125 mm |
| Adjustable window | 40 mm (85–125 mm) |
| Adjuster thread | M5×0.8 |
| Port size | M5×0.8 |
|---|---|
| Operating pressure | 0.15 – 0.7 MPa |
| Proof pressure | 1.2 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 50 – 800 mm/s |
| Cushion | Elastic bumper (both ends) |
| Max standard stroke | Up to 200 mm |
PBJ is a double-rod cylinder: the rear rod carries the stroke adjuster, which sets the stroke end within the adjustable window. Confirm the set position against the product label before installation.
Theoretical Output Force (Ø12mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 46.7 N | 46.7 N |
| 0.7 MPa (max) | 65.4 N | 65.4 N |
The rear rod passes through the rear cover, so both piston faces lose rod area: push is shown at the annular-area value (conservative), lower than a single-rod PB push of the same bore. Size with a friction margin.
Model Code: Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S
| PBJ | JIS pen-size adjustable-stroke mini-cylinder series. |
|---|---|
| 12 | Bore size in mm. |
| ×125 | Nominal stroke length in mm. |
| -40 | Adjustable-stroke window in mm (10/20/30/40/50/75/100). |
| S | Built-in magnet for magnetic-switch position sensing (omit = no magnet). |
Fixed body — no separate back-cover code. Mounting accessories: LB, FA. Related PB-family variants: PB (fixed stroke), PBD (double rod), PBR (front-mount).
Where the Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S Is Used
Changeover Fixtures
Dial in the exact retract distance during product changeovers without machining new hard stops or ordering alternate cylinders.
Trial Insertion Stops
Fine-tune the depth of a press or insertion tool on the machine floor by turning the rear screw, locking the nut once the perfect hit is found.
Variable Depth Pick
Adjust the back position for picking parts of varying heights, using the integrated magnet to confirm end-of-stroke sensing.
Is the Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S the Right Cylinder?
Stepping down to a 10 mm bore drops push to 39.3 N, while a 16 mm bore raises it to 100.5 N. The M5x0.8 air port is fixed by the bore size. Remember that only the retract position is field-settable; the extend end is fixed. Always re-tighten the lock nut after setting the rear screw to prevent vibration drift.
Confirm your ordering essentials: 12 mm bore, 125 mm nominal stroke, 40 mm window, built-in S magnet, and any LB or FA mount. The Ø5 mm piston rod is built for coaxial thrust; over this 125 mm stroke or with off-axis loads, add an external linear bearing to prevent side-load damage.
Quick checklist
- ✓ Need to fine-tune the end position on site
- ✓ Retract end sits within 85–125 mm
- ✓ Force at your working pressure
- ✓ Magnet (S) for sensors?
- ✓ Access to the rear adjuster screw
- ✓ Keep the load coaxial — avoid side load
Installation & Maintenance Notes
- check Use clean air filtered to 40µm or finer.
- check Keep within 0.15 – 0.7 MPa operating pressure.
- check Set the adjuster, then re-lock the check nut.
- check Double rod: the rear rod carries the stroke adjuster.
- check Keep the load coaxial; avoid side load on the thin rod.
- check Do not dismantle the front or back cover.
Airtac PBJ Adjustable Pen-Type Cylinder PBJ12X125-40S FAQ
The effective stroke range is 85-125 mm. Force is identical to a standard PB double-acting cylinder: push is 56.5 N and pull is 46.7 N at 0.5 MPa. At the 0.7 MPa maximum, push is 79.1 N and pull is 65.4 N.
A rear M5x0.8 screw shortens the retract end only; the extend end is fixed. You must re-tighten the lock nut after setting to prevent vibration drift. The built-in S magnet works with AirTAC reed or electronic switches.
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 PBJ Pen-Size Cylinders
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